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Lum EL, Bunnapradist S, Wiseman AC, Gurakar A, Ferrey A, Reddy U, Al Ammary F. Novel indications for referral and care for simultaneous liver kidney transplant recipients. Curr Opin Nephrol Hypertens 2024; 33:354-360. [PMID: 38345405 PMCID: PMC10990015 DOI: 10.1097/mnh.0000000000000970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
PURPOSE OF REVIEW Kidney dysfunction is challenging in liver transplant candidates to determine whether it is reversible or not. This review focuses on the pertinent data on how to best approach liver transplant candidates with kidney dysfunction in the current era after implementing the simultaneous liver kidney (SLK) allocation policy and safety net. RECENT FINDINGS The implementation of the SLK policy inverted the steady rise in SLK transplants and improved the utilization of high-quality kidneys. Access to kidney transplantation following liver transplant alone (LTA) increased with favorable outcomes. Estimating GFR in liver transplant candidates remains challenging, and innovative methods are needed. SLK provided superior patient and graft survival compared to LTA only for patients with advanced CKD and dialysis at least 3 months. SLK can provide immunological protection against kidney rejection in highly sensitized candidates. Post-SLK transplant care is complex, with an increased risk of complications and hospitalization. SUMMARY The SLK policy improved kidney access and utilization. Transplant centers are encouraged, under the safety net, to reserve SLK for liver transplant candidates with advanced CKD or dialysis at least 3 months while allowing lower thresholds for highly sensitized patients. Herein, we propose a practical approach to liver transplant candidates with kidney dysfunction.
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Affiliation(s)
- Erik L. Lum
- Department of Medicine, University of California Los Angeles, Los Angeles, California
| | - Suphamai Bunnapradist
- Department of Medicine, University of California Los Angeles, Los Angeles, California
| | | | - Ahmet Gurakar
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Antoney Ferrey
- Department of Medicine, University of California Irvine, Orange, California, USA
| | - Uttam Reddy
- Department of Medicine, University of California Irvine, Orange, California, USA
| | - Fawaz Al Ammary
- Department of Medicine, University of California Irvine, Orange, California, USA
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2
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Schaenman J, Rossetti M, Pickering H, Sunga G, Wilhalme H, Elashoff D, Zhang Q, Hickey M, Reddy U, Danovitch G, Reed EF, Bunnapradist S. Preservation of Antiviral Immunologic Efficacy Without Alloimmunity After Switch to Belatacept in Calcineurin Inhibitor-Intolerant Patients. Kidney Int Rep 2022; 8:126-140. [PMID: 36644348 PMCID: PMC9832066 DOI: 10.1016/j.ekir.2022.10.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 09/18/2022] [Accepted: 10/10/2022] [Indexed: 11/09/2022] Open
Abstract
Introduction Belatacept has shown potential for prevention of rejection after kidney transplantation, given its demonstration of reduced nephrotoxicity in combination with absence of significant incidence of rejection. However, concerns have been raised regarding increased risk of viral infection. Methods We set out to explore the impact of the switch to belatacept on alloimmune and antiviral immunity through the study of patients switched from calcineurin inhibitor (CNI) to belatacept within 3 months of kidney transplantation compared with a matched cohort of control patients on a CNI-based regimen. Results After the switch to belatacept, immune phenotyping demonstrated a decrease in naive and an increase in terminally differentiated effector memory (TMRA) T cells, with no significant difference compared with control patients. Donor-specific immune response, measured by intracellular cytokine staining (ICS), did not change significantly either by single or double cytokine secretion, but it was associated with the appearance of donor-specific antibody (DSA) in the control but not the belatacept cohort (P = 0.039 for naive and P = 0.002 for TMRA subtypes). Increased incidence of de novo DSA development was observed in the control group (P = 0.035). Virus-specific immune response, as measured by ICS in response to cytomegalovirus (CMV) or Epstein-Barr virus (EBV), was similar in both groups and stable over time. Conclusion We found that belatacept use was associated with an absence of alloreactivity without impact on immune phenotype, while preserving the antiviral immune response, for patients switched from a CNI-based regimen. In parallel, the antiviral immune response against CMV and EBV was preserved after the belatacept switch (clinicaltrials.gov: NCT01953120).
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Affiliation(s)
- Joanna Schaenman
- Division of Infectious Disease, Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Maura Rossetti
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Harry Pickering
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Gemalene Sunga
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Holly Wilhalme
- Department of Medicine Biostatistics Core, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - David Elashoff
- Department of Medicine Biostatistics Core, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Qiuheng Zhang
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Michelle Hickey
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Uttam Reddy
- Division of Kidney Transplantation, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Gabriel Danovitch
- Division of Kidney Transplantation, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Elaine F. Reed
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Suphamai Bunnapradist
- Division of Kidney Transplantation, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA,Correspondence: Suuphamai Bunnapradist, 200 UCLA Medical Plaza, Suite 565, Los Angeles, CA 90095, USA.
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3
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Nguyen L, Souccar S, Zuckerman JE, Chen JLT, Katrivesis J, Abi-Jaoudeh N, Lee LX, Reddy U, Baraghoush A, Morrison DE, Li X, Wang B, Lau WL. Kidney biopsy; challenges with peri-procedural management. J Nephropathol 2021. [DOI: 10.34172/jnp.2022.17222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Native kidney biopsies are high-risk for bleeding complications due to the vascularity of the kidney and the inability to compress the biopsy site within a deep retroperitoneal location. Recommended parameters to minimize bleeding risk include a platelet count above 100 x 109 /L, hemoglobin above 10 g/dL, systolic blood pressure <140 mm Hg, and minimizing the number of biopsy cores. In this paper we present patient cases to discuss management of other factors pertinent to kidney biopsy planning including interruption of anticoagulation, treatment of anxiety which can elevate blood pressure, and use of Doppler. Undiagnosed chronic kidney disease can affect triaging of tissue to light, immunofluorescence and electron microscopy, as sclerosed glomeruli are difficult to visualize in fresh cores. It is recommended to have a back-up retrieval protocol in place to obtain immunofluorescence and electron microscopy results, in the event that only limited kidney tissue was acquired for light histology. A collaborative effort between nephrology, interventional radiology and pathology is essential to optimize the diagnostic yield while minimizing bleeding risk with kidney biopsies. Of paramount importance is physician judgment of whether there is an acceptable balance of benefits/risks to proceed with a kidney biopsy.
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Affiliation(s)
- Lawrence Nguyen
- Division of Nephrology, Department of Medicine, University of California, Irvine, CA, USA
| | - Sami Souccar
- Department of Pathology, University of California, Irvine, CA, USA
| | - Jonathan E. Zuckerman
- 3Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at University of California, Los Angeles, CA, USA
| | - Joline L. T. Chen
- Division of Nephrology, Department of Medicine, University of California, Irvine, CA, USA
- 4Nephrology Section, Long Beach Veteran Affairs Healthcare System, Long Beach, CA, USA
| | - James Katrivesis
- 5Department of Radiological Sciences, University of California, Irvine, CA, USA
| | - Nadine Abi-Jaoudeh
- 5Department of Radiological Sciences, University of California, Irvine, CA, USA
| | - Lisa X Lee
- Division of Hematology/Oncology, Department of Medicine, University of California, Irvine, CA, USA
| | - Uttam Reddy
- Division of Nephrology, Department of Medicine, University of California, Irvine, CA, USA
| | | | - Debra E. Morrison
- Department of Anesthesiology, University of California, Irvine, CA, USA
| | - Xiaodong Li
- Department of Pathology, University of California, Irvine, CA, USA
| | - Beverly Wang
- Department of Pathology, University of California, Irvine, CA, USA
| | - Wei Ling Lau
- Division of Nephrology, Department of Medicine, University of California, Irvine, CA, USA
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4
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Son SL, Allshouse AA, Page JM, Debbink MP, Pinar H, Reddy U, Gibbins KJ, Stoll BJ, Parker CB, Dudley DJ, Varner MW, Silver RM. Stillbirth and fetal anomalies: secondary analysis of a case-control study. BJOG 2021; 128:252-258. [PMID: 32946651 PMCID: PMC7902300 DOI: 10.1111/1471-0528.16517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/14/2020] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Approximately 10% of stillbirths are attributed to fetal anomalies, but anomalies are also common in live births. We aimed to assess the relationship between anomalies, by system and stillbirth. DESIGN Secondary analysis of a prospective, case-control study. SETTING Multicentre, 59 hospitals in five regional catchment areas in the USA. POPULATION OR SAMPLE All stillbirths and representative live birth controls. METHODS Standardised postmortem examinations performed in stillbirths, medical record abstraction for stillbirths and live births. MAIN OUTCOME MEASURES Incidence of major anomalies, by type, compared between stillbirths and live births with univariable and multivariable analyses using weighted analysis to account for study design and differential consent. RESULTS Of 465 singleton stillbirths included, 23.4% had one or more major anomalies compared with 4.3% of 1871 live births. Having an anomaly increased the odds of stillbirth; an increasing number of anomalies was more highly associated with stillbirth. Regardless of organ system affected, the presence of an anomaly increased the odds of stillbirth. These relationships remained significant if stillbirths with known genetic abnormalities were excluded. After multivariable analyses, the adjusted odds ratio (aOR) of stillbirth for any anomaly was 4.33 (95% CI 2.80-6.70) and the systems most strongly associated with stillbirth were cystic hygroma (aOR 29.97, 95% CI 5.85-153.57), and thoracic (aOR16.18, 95% CI 4.30-60.94) and craniofacial (aOR 35.25, 95% CI 9.22-134.68) systems. CONCLUSIONS In pregnancies affected by anomalies, the odds of stillbirth are higher with increasing numbers of anomalies. Anomalies of nearly any organ system increased the odds of stillbirth even when adjusting for gestational age and maternal race. TWEETABLE ABSTRACT Stillbirth risk increases with anomalies of nearly any organ system and with number of anomalies seen.
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Affiliation(s)
- S L Son
- Division of Maternal-Fetal Medicine, University of Utah Health, Salt Lake City, UT, USA
- Division of Maternal-Fetal Medicine, Intermountain Healthcare, Salt Lake City, UT, USA
| | - A A Allshouse
- Division of Maternal-Fetal Medicine, University of Utah Health, Salt Lake City, UT, USA
| | - J M Page
- Division of Maternal-Fetal Medicine, University of Utah Health, Salt Lake City, UT, USA
- Division of Maternal-Fetal Medicine, Intermountain Healthcare, Salt Lake City, UT, USA
| | - M P Debbink
- Division of Maternal-Fetal Medicine, University of Utah Health, Salt Lake City, UT, USA
- Division of Maternal-Fetal Medicine, Intermountain Healthcare, Salt Lake City, UT, USA
| | - H Pinar
- Division of Perinatal Pathology, Alpert Medical School of Brown University, Providence, RI, USA
| | - U Reddy
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Yale School of Medicine, New Haven, CT, USA
| | - K J Gibbins
- Division of Maternal-Fetal Medicine, University of Utah Health, Salt Lake City, UT, USA
| | - B J Stoll
- Department of Pediatrics, University of Texas Health McGovern Medical School, Houston, TX, USA
| | - C B Parker
- RTI International, Research Triangle Park, NC, USA
| | - D J Dudley
- University of Virginia School of Medicine, Charlottesville, VA, USA
| | - M W Varner
- Division of Maternal-Fetal Medicine, University of Utah Health, Salt Lake City, UT, USA
- Division of Maternal-Fetal Medicine, Intermountain Healthcare, Salt Lake City, UT, USA
| | - R M Silver
- Division of Maternal-Fetal Medicine, University of Utah Health, Salt Lake City, UT, USA
- Division of Maternal-Fetal Medicine, Intermountain Healthcare, Salt Lake City, UT, USA
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5
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Okuda Y, Streja E, Rhee CM, Tantisattamo E, Reddy U, Laster M, Tang Y, Rajpoot D, Molnar MZ, Ichii H, Obi Y, Kalantar-Zadeh K. Association of age with risk of first and subsequent allograft failure and mortality among young kidney transplant recipients in the USA - a retrospective cohort study. Transpl Int 2020; 33:1503-1515. [PMID: 32779214 DOI: 10.1111/tri.13717] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 03/20/2020] [Accepted: 08/05/2020] [Indexed: 11/30/2022]
Abstract
Adolescent age may be a high-risk period for kidney allograft failure. However, the knowledge on this topic is limited mostly to the first transplant. Among 20 960 patients aged ≤21 years at the first kidney transplantation from the US Renal Data System, we evaluated the association of age at the first kidney transplant with risk for the first and subsequent graft failures (1st, 2nd, and 3rd) using the conditional risk set model for recurrent time-to-event data. The median age was 15 (interquartile range: 9-18) years, and 18% received transplants twice or more during a median follow-up of 9.7 years. The risk for graft failures was highest in 16 to <18 years old with an adjusted hazard ratio (aHR) of 1.93 (95% CI, 1.73-2.15; reference: <3 years). When separately analyzed, the highest risk was observed in 17, 19, and 21 years old for the first, second, and third transplant, respectively. Those 16 to <18 years were also strongly associated with the highest risk for death after returning to dialysis (aHR, 4.01; 95% CI, 2.82-5.71). Adolescent recipients remain at high risk for allograft failure for a long time, which may result in high mortality risk, even though they surpass this high-risk period soon after the first transplant.
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Affiliation(s)
- Yusuke Okuda
- Division of Nephrology and Hypertension, School of Medicine, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine, Orange, CA, USA.,Department of Pediatrics, Kitasato University School of Medicine, Kanagawa, JAPAN
| | - Elani Streja
- Division of Nephrology and Hypertension, School of Medicine, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine, Orange, CA, USA
| | - Connie M Rhee
- Division of Nephrology and Hypertension, School of Medicine, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine, Orange, CA, USA
| | - Ekamol Tantisattamo
- Division of Nephrology and Hypertension, School of Medicine, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine, Orange, CA, USA
| | - Uttam Reddy
- Division of Nephrology and Hypertension, School of Medicine, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine, Orange, CA, USA
| | - Marciana Laster
- David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.,Division of Pediatric Nephrology, Mattel Children's Hospital at UCLA, Los Angeles, CA, USA
| | - Ying Tang
- Division of Nephrology and Hypertension, School of Medicine, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine, Orange, CA, USA.,Department of Pediatric Nephrology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Deepak Rajpoot
- Miller Children Hospital, Long Beach, CA, USA.,Department of Pediatrics, School of Medicine, University of California Irvine, Orange, CA, USA
| | - Miklos Z Molnar
- James D Eason Transplant Institute, Methodist University Hospital, Memphis, TN, USA.,Department of Surgery, University of Tennessee Health Science Center, Memphis, TN, USA.,Department of Transplantation and Surgery, Semmelweis University, Budapest, Hungary.,Division of Nephrology, Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Hirohito Ichii
- Department of Surgery, University of California Irvine, Orange, CA, USA
| | - Yoshitsugu Obi
- Division of Nephrology, Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Kamyar Kalantar-Zadeh
- Division of Nephrology and Hypertension, School of Medicine, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine, Orange, CA, USA
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6
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Ferrey AJ, Choi G, Hanna RM, Chang Y, Tantisattamo E, Ivaturi K, Park E, Nguyen L, Wang B, Tonthat S, Rhee CM, Reddy U, Lau WL, Huang SS, Gohil S, Amin AN, Hsieh L, Cheng TT, Lee RA, Kalantar-Zadeh K. A Case of Novel Coronavirus Disease 19 in a Chronic Hemodialysis Patient Presenting with Gastroenteritis and Developing Severe Pulmonary Disease. Am J Nephrol 2020; 51:337-342. [PMID: 32222713 PMCID: PMC7179539 DOI: 10.1159/000507417] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Accepted: 03/24/2020] [Indexed: 12/22/2022]
Abstract
Novel coronavirus disease 2019 (COVID-19) is a highly infectious, rapidly spreading viral disease with an alarming case fatality rate up to 5%. The risk factors for severe presentations are concentrated in patients with chronic kidney disease, particularly patients with end-stage renal disease (ESRD) who are dialysis dependent. We report the first US case of a 56-year-old nondiabetic male with ESRD secondary to IgA nephropathy undergoing thrice-weekly maintenance hemodialysis for 3 years, who developed COVID-19 infection. He has hypertension controlled with angiotensin receptor blocker losartan 100 mg/day and coronary artery disease status-post stent placement. During the first 5 days of his febrile disease, he presented to an urgent care, 3 emergency rooms, 1 cardiology clinic, and 2 dialysis centers in California and Utah. During this interval, he reported nausea, vomiting, diarrhea, and low-grade fevers but was not suspected of COVID-19 infection until he developed respiratory symptoms and was admitted to the hospital. Imaging studies upon admission were consistent with bilateral interstitial pneumonia. He was placed in droplet-eye precautions while awaiting COVID-19 test results. Within the first 24 h, he deteriorated quickly and developed acute respiratory distress syndrome (ARDS), requiring intubation and increasing respiratory support. Losartan was withheld due to hypotension and septic shock. COVID-19 was reported positive on hospital day 3. He remained in critical condition being treated with hydroxychloroquine and tocilizumab in addition to the standard medical management for septic shock and ARDS. Our case is unique in its atypical initial presentation and highlights the importance of early testing.
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Affiliation(s)
- Antoney J Ferrey
- Department of Medicine, Division of Nephrology, Hypertension and Kidney Transplantation, University of California Irvine Medical Center, Orange, California, USA
- Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine School of Medicine, Orange, California, USA
- Division of Nephrology, Hypertension and Kidney Transplantation, Department of Medicine, University of California Irvine School of Medicine, Orange, California, USA
| | - Grace Choi
- Department of Medicine, Division of Nephrology, Hypertension and Kidney Transplantation, University of California Irvine Medical Center, Orange, California, USA
- Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine School of Medicine, Orange, California, USA
- Division of Nephrology, Hypertension and Kidney Transplantation, Department of Medicine, University of California Irvine School of Medicine, Orange, California, USA
| | - Ramy M Hanna
- Department of Medicine, Division of Nephrology, Hypertension and Kidney Transplantation, University of California Irvine Medical Center, Orange, California, USA
- Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine School of Medicine, Orange, California, USA
- Division of Nephrology, Hypertension and Kidney Transplantation, Department of Medicine, University of California Irvine School of Medicine, Orange, California, USA
| | - Yongen Chang
- Department of Medicine, Division of Nephrology, Hypertension and Kidney Transplantation, University of California Irvine Medical Center, Orange, California, USA
- Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine School of Medicine, Orange, California, USA
- Division of Nephrology, Hypertension and Kidney Transplantation, Department of Medicine, University of California Irvine School of Medicine, Orange, California, USA
| | - Ekamol Tantisattamo
- Department of Medicine, Division of Nephrology, Hypertension and Kidney Transplantation, University of California Irvine Medical Center, Orange, California, USA
- Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine School of Medicine, Orange, California, USA
- Division of Nephrology, Hypertension and Kidney Transplantation, Department of Medicine, University of California Irvine School of Medicine, Orange, California, USA
| | - Kaushik Ivaturi
- Department of Medicine, Division of Nephrology, Hypertension and Kidney Transplantation, University of California Irvine Medical Center, Orange, California, USA
- Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine School of Medicine, Orange, California, USA
- Division of Nephrology, Hypertension and Kidney Transplantation, Department of Medicine, University of California Irvine School of Medicine, Orange, California, USA
| | - Elisa Park
- Department of Medicine, Division of Nephrology, Hypertension and Kidney Transplantation, University of California Irvine Medical Center, Orange, California, USA
- Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine School of Medicine, Orange, California, USA
- Division of Nephrology, Hypertension and Kidney Transplantation, Department of Medicine, University of California Irvine School of Medicine, Orange, California, USA
| | - Lawrence Nguyen
- Department of Medicine, Division of Nephrology, Hypertension and Kidney Transplantation, University of California Irvine Medical Center, Orange, California, USA
- Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine School of Medicine, Orange, California, USA
- Division of Nephrology, Hypertension and Kidney Transplantation, Department of Medicine, University of California Irvine School of Medicine, Orange, California, USA
| | - Brian Wang
- Department of Medicine, Division of Nephrology, Hypertension and Kidney Transplantation, University of California Irvine Medical Center, Orange, California, USA
- Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine School of Medicine, Orange, California, USA
- Division of Nephrology, Hypertension and Kidney Transplantation, Department of Medicine, University of California Irvine School of Medicine, Orange, California, USA
| | - Sam Tonthat
- Department of Medicine, Division of Nephrology, Hypertension and Kidney Transplantation, University of California Irvine Medical Center, Orange, California, USA
- Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine School of Medicine, Orange, California, USA
- Division of Nephrology, Hypertension and Kidney Transplantation, Department of Medicine, University of California Irvine School of Medicine, Orange, California, USA
| | - Connie M Rhee
- Department of Medicine, Division of Nephrology, Hypertension and Kidney Transplantation, University of California Irvine Medical Center, Orange, California, USA
- Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine School of Medicine, Orange, California, USA
- Division of Nephrology, Hypertension and Kidney Transplantation, Department of Medicine, University of California Irvine School of Medicine, Orange, California, USA
- Department of Medicine, Nephrology Section, Tibor Rubin Veterans Affairs Long Beach Healthcare System, Long Beach, California, USA
| | - Uttam Reddy
- Department of Medicine, Division of Nephrology, Hypertension and Kidney Transplantation, University of California Irvine Medical Center, Orange, California, USA
- Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine School of Medicine, Orange, California, USA
- Division of Nephrology, Hypertension and Kidney Transplantation, Department of Medicine, University of California Irvine School of Medicine, Orange, California, USA
| | - Wei Ling Lau
- Department of Medicine, Division of Nephrology, Hypertension and Kidney Transplantation, University of California Irvine Medical Center, Orange, California, USA
- Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine School of Medicine, Orange, California, USA
- Division of Nephrology, Hypertension and Kidney Transplantation, Department of Medicine, University of California Irvine School of Medicine, Orange, California, USA
- Department of Medicine, Nephrology Section, Tibor Rubin Veterans Affairs Long Beach Healthcare System, Long Beach, California, USA
| | - Susan S Huang
- Division of Infectious Diseases, University of California Irvine School of Medicine, Epidemiology and Infection Prevention Program, UC Irvine Health, Orange, California, USA
| | - Shruti Gohil
- Division of Infectious Diseases, University of California Irvine School of Medicine, Epidemiology and Infection Prevention Program, UC Irvine Health, Orange, California, USA
| | - Alpesh N Amin
- Department of Medicine, Hospitalist Program, University of California Irvine Medical Center, Orange, California, USA
| | - Lanny Hsieh
- Department of Medicine, Hospitalist Program and Division of Infectious Disease, University of California Irvine Medical Center, Orange, California, USA
| | - Timmy T Cheng
- Department of Medicine, Division of Pulmonology and Critical Care, University of California Irvine Medical Center, Orange, California, USA
| | - Richard A Lee
- Department of Medicine, Division of Pulmonology and Critical Care, University of California Irvine Medical Center, Orange, California, USA
| | - Kamyar Kalantar-Zadeh
- Department of Medicine, Division of Nephrology, Hypertension and Kidney Transplantation, University of California Irvine Medical Center, Orange, California, USA,
- Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine School of Medicine, Orange, California, USA,
- Division of Nephrology, Hypertension and Kidney Transplantation, Department of Medicine, University of California Irvine School of Medicine, Orange, California, USA,
- Department of Medicine, Nephrology Section, Tibor Rubin Veterans Affairs Long Beach Healthcare System, Long Beach, California, USA,
- Department of Medicine, Division of Pulmonology and Critical Care, University of California Irvine Medical Center, Orange, California, USA,
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7
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Hasjim BJ, Fujitani RM, Chen SL, Donayre C, Kuo IJ, Raza A, Reddy U, Ichii H, Kabutey NK. Utilization of Carbon Dioxide Angiography and Percutaneous Balloon Angioplasty for Treatment of Transplant Renal Artery Stenosis. Ann Vasc Surg 2019; 65:10-16. [PMID: 31712187 DOI: 10.1016/j.avsg.2019.11.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Revised: 09/23/2019] [Accepted: 11/04/2019] [Indexed: 11/18/2022]
Abstract
BACKGROUND Transplant renal artery stenosis (TRAS) may lead to graft dysfunction and failure. Progressive deterioration of renal allograft function may be exacerbated by contrast-induced nephrotoxicity during iodine contrast administration for renovascular imaging of allografts. We present our institutional experience of endovascular management for TRAS using CO2 digital subtraction angiography (CO2-DSA) and balloon angioplasty to manage failing renal transplants. METHODS Four patients with renal allografts from March 2017-May 2018 were referred for graft dysfunction and pending renal transplant failure. Indications for referral included refractory hypertension, decreasing renal functioning, and elevated renovascular systolic velocities. RESULTS Median age of the four patients was 41.5 years (22-60 years). There were two male and female patients. Chronic hypertension and type 2 diabetes mellitus were the most common comorbidities. An average total of 75 mL of CO2 was used, supplemented with 17.4 mL of iodinated contrast. All patients had improvements in renal function following intervention with a mean decrease in systolic and diastolic blood pressure of 25.8% and 21.4%, respectively. We also observed a mean decrease of BUN by 13.6% and creatinine by 37.4%. Additionally, eGFR increased by 37.7%. All allografts survived after surgery, and only one patient required repeat angioplasty for recurrence. CONCLUSIONS CO2-DSA with balloon angioplasty can be successfully utilized to salvage deteriorating kidney allograft function in patients with TRAS.
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Affiliation(s)
- Bima J Hasjim
- Division of Vascular Surgery, Department of Surgery, University of California, Irvine, Orange, CA
| | - Roy M Fujitani
- Division of Vascular Surgery, Department of Surgery, University of California, Irvine, Orange, CA
| | - Samuel L Chen
- Division of Vascular Surgery and Endovascular Therapy, Hospital of the University of Pennsylvania, Philadelphia, PA
| | - Carlos Donayre
- Division of Vascular Surgery, Department of Surgery, University of California, Irvine, Orange, CA
| | - Isabella J Kuo
- Division of Vascular Surgery, Department of Surgery, University of California, Irvine, Orange, CA
| | - Aamir Raza
- Division of Nephrology and Hypertension, Department of Medicine, University of California, Irvine, Orange, CA
| | - Uttam Reddy
- Division of Nephrology and Hypertension, Department of Medicine, University of California, Irvine, Orange, CA
| | - Hirohito Ichii
- Division of Transplant Surgery, Department of Surgery, University of California, Irvine, Orange, CA
| | - Nii-Kabu Kabutey
- Division of Vascular Surgery, Department of Surgery, University of California, Irvine, Orange, CA.
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8
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Smith M, Reddy U, Robba C, Sharma D, Citerio G. Acute ischaemic stroke: challenges for the intensivist. Intensive Care Med 2019; 45:1177-1189. [PMID: 31346678 DOI: 10.1007/s00134-019-05705-y] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 07/17/2019] [Indexed: 12/25/2022]
Abstract
PURPOSE To provide an update about the rapidly developing changes in the critical care management of acute ischaemic stroke patients. METHODS A narrative review was conducted in five general areas of acute ischaemic stroke management: reperfusion strategies, anesthesia for endovascular thrombectomy, intensive care unit management, intracranial complications, and ethical considerations. RESULTS The introduction of effective reperfusion strategies, including IV thrombolysis and endovascular thrombectomy, has revolutionized the management of acute ischaemic stroke and transformed outcomes for patients. Acute therapeutic efforts are targeted to restoring blood flow to the ischaemic penumbra before irreversible tissue injury has occurred. To optimize patient outcomes, secondary insults, such as hypotension, hyperthermia, or hyperglycaemia, that can extend the penumbral area must also be prevented or corrected. The ICU management of acute ischaemic stroke patients, therefore, focuses on the optimization of systemic physiological homeostasis, management of intracranial complications, and neurological and haemodynamic monitoring after reperfusion therapies. Meticulous blood pressure management is of central importance in improving outcomes, particularly in patients that have undergone reperfusion therapies. CONCLUSIONS While consensus guidelines are available to guide clinical decision making after acute ischaemic stroke, there is limited high-quality evidence for many of the recommended interventions. However, a bundle of medical, endovascular, and surgical strategies, when applied in a timely and consistent manner, can improve long-term stroke outcomes.
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Affiliation(s)
- M Smith
- Neurocritical Care Unit, The National Hospital for Neurology and Neurosurgery, University College London Hospitals, Queen Square, London, UK. .,Department of Medical Physics and Biomedical Engineering, University College London, London, UK.
| | - U Reddy
- Neurocritical Care Unit, The National Hospital for Neurology and Neurosurgery, University College London Hospitals, Queen Square, London, UK
| | - C Robba
- Department of Anaesthesia and Intensive Care, Policlinico San Martino IRCCS for Oncology and Neuroscience, Genoa, Italy
| | - D Sharma
- Division of Neuroanesthesiology and Perioperative Neurosciences, Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, USA
| | - G Citerio
- School of Medicine and Surgery, University of Milan-Bicocca, Milan, Italy.,Neurointensive Care Unit, San Gerardo Hospital, ASST-Monza, Monza, MB, Italy
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9
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Lertdumrongluk P, Streja E, Rhee CM, Moradi H, Chang Y, Reddy U, Tantisattamo E, Kalantar-Zadeh K, Kopp JB. Survival Advantage of African American Dialysis Patients with End-Stage Renal Disease Causes Related to APOL1. Cardiorenal Med 2019; 9:212-221. [PMID: 30995638 DOI: 10.1159/000496472] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 12/22/2018] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Observational studies show that African American (AA) dialysis patients have longer survival than European Americans. We hypothesized that apolipoprotein L1 (APOL1) genetic variation, associated with nephropathy in AAs, contributes to the survival advantage in AA dialysis patients. METHODS We examined the association between race and mortality among 37,097 adult dialysis patients, including 54% AAs and 46% European Americans from a large dialysis organization (entry period from July 2001 to June 2006, follow-up through June 2007), within each cause of end-stage renal disease (ESRD) category associated with APOL1 renal risk variants using Cox proportional hazard models. RESULTS AA dialysis patients had numerically lower mortality than their European American counterparts for all causes of ESRD. The mortality reduction among AAs compared to European Americans was statistically significant in patients with ESRD attributed to diabetes mellitus, hypertension, and APOL1-enriched glomerulonephritis (GN) (HR [95% CI]: 0.69 [0.66-0.72], 0.73 [0.68-0.79], and 0.89 [0.79-0.99], respectively); these are conditions in which APOL1 variants promote kidney disease. By contrast, the significant survival advantage of AA dialysis patients was not observed in patients with ESRD attributed to other kidney disease (including polycystic kidney disease, interstitial nephritis, and pyelonephritis) and other GN, which are not associated with APOL1 variants. CONCLUSIONS These data suggest the hypothesis that the relative survival advantage of AA dialysis patients may be related to APOL1 variation. Further large population-based genetic studies are required to test this hypothesis.
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Affiliation(s)
- Paungpaga Lertdumrongluk
- Harold Simmons Center for Kidney Disease Research and Epidemiology, Orange, California, USA.,Panyananthaphikkhu Chonprathan Medical Center, Srinakharinwirot University, Nonthaburi, Thailand
| | - Elani Streja
- Harold Simmons Center for Kidney Disease Research and Epidemiology, Orange, California, USA.,University of California Irvine School of Medicine, Orange, California, USA
| | - Connie M Rhee
- Harold Simmons Center for Kidney Disease Research and Epidemiology, Orange, California, USA.,University of California Irvine School of Medicine, Orange, California, USA
| | - Hamid Moradi
- Harold Simmons Center for Kidney Disease Research and Epidemiology, Orange, California, USA
| | - Yongen Chang
- Harold Simmons Center for Kidney Disease Research and Epidemiology, Orange, California, USA
| | - Uttam Reddy
- Harold Simmons Center for Kidney Disease Research and Epidemiology, Orange, California, USA
| | - Ekamol Tantisattamo
- Harold Simmons Center for Kidney Disease Research and Epidemiology, Orange, California, USA
| | - Kamyar Kalantar-Zadeh
- Harold Simmons Center for Kidney Disease Research and Epidemiology, Orange, California, USA.,University of California Irvine School of Medicine, Orange, California, USA
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10
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Asif H, Craven CL, Reddy U, Watkins LD, Toma AK. P109 Experience of tunnelled vs. bolt EVDs on the intensive care unit. J Neurol Neurosurg Psychiatry 2019. [DOI: 10.1136/jnnp-2019-abn.164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
ObjectivesThe placement of an external ventricular drain (EVD) is a common neurosurgical operation that carries great benefit in acute hydrocephalus but is not without risk. In our centre, bolt EVDs (B-EVD) are being placed in favour of tunnelled EVDs (T-EVD). The former has allowed for urgent CSF diversion in ITU. We compared EVD survival and complication rates between the two types of EVDs.DesignSingle centre prospective case-cohort.SubjectsTwenty-five patients with B-EVDs and thirty-four patients with T-EVDs.MethodsClinical notes and radiographic reports were collected before and after the placement of EVDs for patients in ITU between January 2017 and June 2018.ResultsFourteen of the 25 B-EVDs were placed on ITU, of which 2 were under stealth guidance. All 34 T-EVDs were placed in theatre. Mean time to CSF access after decision for diversion was 134 min in the B-EVD group and 227 min in the T-EVD group (p<0.05). Mean survival was 35 days for B-EVDs and 29 days for T-EVDs (p<0.05). Eight T-EVDs went onto be replaced as B-EVDs due to retraction or infection. Complications including infection, detachment or retraction were higher in the T-EVD group at 32% compared to 20% in the B-EVD group.ConclusionsBolt EVDs have a lower frequency of complications and higher survival compared to tunnelled EVDs. Since B-EVDs require fewer resources they can be placed faster and on ITU.
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11
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Craven CL, Reddy U, Asif H, Watkins LD, Toma AK. WM1-7 Brain parenchymal oxygen monitoring in delayed cerebral ischaemia. J Neurol Neurosurg Psychiatry 2019. [DOI: 10.1136/jnnp-2019-abn.4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
ObjectivesAt this single centre, tri-modal monitoring of ICP, temperature and direct brain tissue oxygen tension (PbtO2) is used to guide management of delayed cerebral ischaemia (DCI). We describe our experience of PbtO2 monitoring and its relationship with symptoms of DCI, regional cerebral blood flow (rCBF, perfusion imaging), intra-arterial chemical angioplasty and CSF diversion.DesignProspective cohort.SubjectsPatients with aSAH who underwent over 24 hours of multi-modal PbtO2, temperature and intracranial pressure (ICP) monitoring via a Raumedic NEUROVENT-PTO probe.MethodsLongitudinal analysis of PbtO2 values, presented as mmHg (mean±SD).ResultsAnalysis of 1392 hours of tri-modal monitoring in 13 SAH patients. PbtO2 decreases >50% consistently reproduced focal neurological deficit. Symptomatic PbtO2 values ranged from 12–20 mmHg. Of the six patients who had reduced rCBF, all had a mean PbtO2 <15 mmHg. Five patients underwent intra-arterial chemical angioplasty (10 mg Verapamil in 100 ml NaCl over 30–40 mins). PbtO2 increased by at least 30% for 3.4±0.47 hours. CSF diversion resulted in a sustained mean increase in PbtO2 of 7.6±2.94 mmHg over the first 5 min (p=0.034).ConclusionsPbtO2 <15 mmHg may predict development of a clinical deficit. Chemical angioplasty resulted in a pronounced but short-lived increase in PbtO2. CSF diversion resulted in a persistent increase in PbtO2. PbtO2 targeted management may be a valuable addition to the clinicians’ arsenal against DCI.
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12
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Andrews PJD, Verma V, Healy M, Lavinio A, Curtis C, Reddy U, Andrzejowski J, Foulkes A, Canestrini S. Targeted temperature management in patients with intracerebral haemorrhage, subarachnoid haemorrhage, or acute ischaemic stroke: consensus recommendations. Br J Anaesth 2018; 121:768-775. [PMID: 30236239 DOI: 10.1016/j.bja.2018.06.018] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 05/30/2018] [Accepted: 07/02/2018] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND A modified Delphi approach was used to identify a consensus on practical recommendations for the use of non-pharmacological targeted temperature management in patients with intracerebral haemorrhage, subarachnoid haemorrhage, or acute ischaemic stroke with non-infectious fever (assumed neurogenic fever). METHODS Nine experts in the management of neurogenic fever participated in the process, involving the completion of online questionnaires, face-to-face discussions, and summary reviews, to consolidate a consensus on targeted temperature management. RESULTS The panel's recommendations are based on a balance of existing evidence and practical considerations. With this in mind, they highlight the importance of managing neurogenic fever using a single protocol for targeted temperature management. Targeted temperature management should be initiated if the patient temperature increases above 37.5°C, once an appropriate workup for infection has been undertaken. This helps prevent prophylactic targeted temperature management use and ensures infection is addressed appropriately. When neurogenic fever is detected, targeted temperature management should be initiated rapidly if antipyretic agents fail to control the temperature within 1 h, and should then be maintained for as long as there is potential for secondary brain damage. The recommended target temperature for targeted temperature management is 36.5-37.5°C. The use of advanced targeted temperature management methods that enable continuous, or near continuous, temperature measurement and precise temperature control is recommended. CONCLUSIONS Given the limited heterogeneous evidence currently available on targeted temperature management use in patients with neurogenic fever and intracerebral haemorrhage, subarachnoid haemorrhage, or acute ischaemic stroke, a Delphi approach was appropriate to gather an expert consensus. To aid in the development of future investigations, the panel provides recommendations for data gathering.
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Affiliation(s)
- P J D Andrews
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK.
| | - V Verma
- Royal London Hospital, London, UK
| | - M Healy
- Royal London Hospital, London, UK
| | - A Lavinio
- Neurosciences and Trauma Critical Care Unit, Addenbrooke's Hospital, Cambridge, UK
| | - C Curtis
- University College London Hospital, London, UK
| | - U Reddy
- National Hospital for Neurology and Neurosurgery, University College London Hospitals NHS Foundation Trust, London, UK
| | - J Andrzejowski
- Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, UK
| | - A Foulkes
- The Walton Centre for Neurology and Neurosurgery, Liverpool, UK
| | - S Canestrini
- King's College Hospital NHS Foundation Trust, London, UK
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13
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14
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Monahan R, Caballero A, Reddy U, Stoll B, Silver B, Saade G, Dudley D. 198: Inadequate prenatal care increases the risk for stillbirth. Am J Obstet Gynecol 2018. [DOI: 10.1016/j.ajog.2017.10.075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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15
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Yu JZ, Rhee CM, Ferrey A, Li A, Jin A, Chang Y, Reddy U, Lau WL, Chou J, Inrig J, Kalantar-Zadeh K. There's no place like home: 35-year patient survival on home hemodialysis. Semin Dial 2017; 31:300-304. [PMID: 29265477 DOI: 10.1111/sdi.12660] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The vast majority of maintenance dialysis patients suffer from poor long-term survival rates and lower levels of health-related quality of life. However, home hemodialysis is a historically significant dialysis modality that has been associated with favorable outcomes as well as greater patient autonomy and control, yet only represents a small minority of the total dialysis performed in the United States. Some potential disadvantages of home hemodialysis include vascular access complications, infection-related hospitalizations, patient fatigue, and attrition. In addition, current barriers and challenges in expanding the utilization of this modality include limited patient and provider education and technical expertise. Here we report a 65-year old male with end-stage renal disease due to Alport's syndrome who has undergone 35 years of uninterrupted thrice-weekly home hemodialysis (ie, every Sunday, Tuesday, and Thursday evening, each session lasting 3 to 3¼ hours in length) using a conventional hemodialysis machine who has maintained a high functional status allowing him to work 6-8 hours per day. The patient has been able to liberalize his dietary and fluid intake while only requiring 3-4 liters of ultrafiltration per treatment, despite having absence of residual kidney function. Through this case of extraordinary longevity and outcomes after 35 years of dialysis and a review of the literature, we illustrate the history of home hemodialysis, its significant clinical and psychosocial advantages, as well as the barriers that hinder its widespread adaptation.
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Affiliation(s)
- Jerry Z Yu
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, CA, USA
| | - Connie M Rhee
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, CA, USA
| | | | - Alex Li
- Northwest Kidney Center, Snoqualmie, WA, USA
| | - Anna Jin
- Tibor Rubin Veterans Affairs Medical Center, Long Beach, CA, USA
| | - Yongen Chang
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, CA, USA
| | - Uttam Reddy
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, CA, USA
| | - Wei Ling Lau
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, CA, USA
| | - Jason Chou
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, CA, USA
| | - Jula Inrig
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, CA, USA
| | - Kamyar Kalantar-Zadeh
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, CA, USA.,St Joseph's Medical Center, Orange, CA, USA
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16
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Shen JI, Hercz D, Barba LM, Wilhalme H, Lum EL, Huang E, Reddy U, Salas L, Vangala S, Norris KC. Association of Citizenship Status With Kidney Transplantation in Medicaid Patients. Am J Kidney Dis 2017; 71:182-190. [PMID: 29128413 DOI: 10.1053/j.ajkd.2017.08.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 08/07/2017] [Indexed: 12/21/2022]
Abstract
BACKGROUND Although individuals classified as nonresident aliens, including undocumented immigrants, are entitled to receive emergency dialysis in the United States regardless of their ability to pay, most states do not provide them with subsidized care for maintenance dialysis or kidney transplantation. We explored whether nonresident aliens have similar outcomes to US citizens after receiving kidney transplants covered by Medicaid, a joint federal and state health insurance program. STUDY DESIGN Retrospective observational cohort study. SETTING & PARTICIPANTS All adult Medicaid patients in the US Renal Data System who received their first kidney transplant from 1990 to 2011. PREDICTOR Citizenship status, categorized as US citizen, nonresident alien, or permanent resident. OUTCOME All-cause transplant loss. MEASUREMENTS HRs and 95% CIs estimated by applying Cox proportional hazards frailty models with transplantation center as a random effect. RESULTS Of 10,495 patients, 8,660 (82%) were US citizens, 1,489 (14%) were permanent residents, and 346 (3%) were nonresident aliens, whom we assumed were undocumented immigrants. Nonresident aliens were younger, healthier, receiving dialysis longer, and more likely to have had a living donor. 71% underwent transplantation in California, and 61% underwent transplantation after 2005. Nonresident aliens had a lower unadjusted risk for transplant loss compared with US citizens (HR, 0.48; 95% CI, 0.35-0.65). Results were attenuated but still significant when adjusted for demographics, comorbid conditions, dialysis, and transplant-related factors (HR, 0.67; 95% CI, 0.46-0.94). LIMITATIONS Citizenship status was self-reported, possible residual confounding. CONCLUSIONS Our study suggests that the select group of insured nonresident aliens who undergo transplantation with Medicaid do just as well as US citizens with Medicaid. Policymakers should consider expanding coverage for kidney transplantation in nonresident aliens, including undocumented immigrants, given the associated high-quality outcomes in these patients.
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Affiliation(s)
- Jenny I Shen
- Division of Nephrology and Hypertension, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, CA; Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA.
| | - Daniel Hercz
- Department of Medicine Statistics Core, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Lilly M Barba
- Division of Nephrology and Hypertension, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, CA; Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Holly Wilhalme
- Department of Medicine Statistics Core, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Erik L Lum
- Division of Nephrology, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Edmund Huang
- Division of Nephrology, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Uttam Reddy
- Division of Nephrology and Hypertension, University of California Irvine, Orange, CA
| | - Leslie Salas
- Division of Nephrology and Hypertension, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, CA
| | - Sitaram Vangala
- Department of Medicine Statistics Core, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Keith C Norris
- Division of General Internal Medicine and Health Services Research, David Geffen School of Medicine at UCLA, Los Angeles, CA
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17
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Dosch AR, Pahl M, Reddy U, Foster CE, Ichii H. Post-transplantation nephroptosis causing recurrent episodes of acute renal failure and hypertension secondary to intermittent vascular torsion of intraperitoneal renal allograft. J Surg Case Rep 2017; 2017:rjx033. [PMID: 28560019 PMCID: PMC5441242 DOI: 10.1093/jscr/rjx033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Revised: 01/28/2017] [Accepted: 04/26/2017] [Indexed: 11/13/2022] Open
Abstract
Nephroptosis is a rare complication in renal transplantation, but one with significant associated risk. Due to non-specific clinical features, there may be a substantial delay in diagnosis and loss of the transplanted kidney due to renal pedicle thrombosis. We present a case of post-transplantation nephroptosis after simultaneous pancreas and kidney transplant, which resulted in accelerated hypertension and reversible acute kidney injury >1 year after transplantation. Prompt detection of this rare entity leading to expeditious surgical intervention is necessary to preserve viability of the renal allograft.
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Affiliation(s)
- Austin R Dosch
- Department of Surgery, University of California, Irvine School of Medicine, Irvine, CA, USA
| | - Madeleine Pahl
- Department of Medicine, University of California, Irvine School of Medicine, Irvine, CA, USA
| | - Uttam Reddy
- Department of Medicine, University of California, Irvine School of Medicine, Irvine, CA, USA
| | - Clarence E Foster
- Department of Surgery, University of California, Irvine School of Medicine, Irvine, CA, USA
| | - Hirohito Ichii
- Department of Surgery, University of California, Irvine School of Medicine, Irvine, CA, USA
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18
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Schaenman J, Korin Y, Sidwell T, Kandarian F, Harre N, Gjertson D, Lum E, Reddy U, Huang E, Pham P, Bunnapradist S, Danovitch G, Veale J, Gritsch H, Reed E. Increased Frequency of BK Virus-Specific Polyfunctional CD8+ T Cells Predict Successful Control of BK Viremia After Kidney Transplantation. Transplantation 2017; 101:1479-1487. [PMID: 27391197 PMCID: PMC5219876 DOI: 10.1097/tp.0000000000001314] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND BK virus infection remains an important cause of loss of allograft function after kidney transplantation. We sought to determine whether polyfunctional T cells secreting multiple cytokines simultaneously, which have been shown to be associated with viral control, could be detected early after start of BK viremia, which would provide insight into the mechanism of successful antiviral control. METHODS Peripheral blood mononuclear cells collected during episodes of BK viral replication were evaluated by multiparameter flow cytometry after stimulation by overlapping peptide pools of BK virus antigen to determine frequency of CD8+ and CD4+ T cells expressing 1 or more cytokines simultaneously, as well as markers of T-cell activation, exhaustion, and maturation. RESULTS BK virus controllers, defined as those with episodes of BK viremia of 3 months or less, had an 11-fold increase in frequency of CD8+ polyfunctional T cells expressing multiple cytokines, as compared with patients with prolonged episodes of BK viremia. Patients with only low level BK viremia expressed low frequencies of polyfunctional T cells. Polyfunctional T cells were predominantly of the effector memory maturation subtype and expressed the cytotoxicity marker CD107a. CONCLUSIONS Noninvasive techniques for immune assessment of peripheral blood can provide insight into the mechanism of control of BK virus replication and may allow for future patient risk stratification and customization of immune suppression at the onset of BK viremia.
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Affiliation(s)
- J.M. Schaenman
- Division of Infectious Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Y. Korin
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - T. Sidwell
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - F. Kandarian
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - N. Harre
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - D. Gjertson
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA
- Department of Biostatistics, UCLA School of Public Health, Los Angeles, CA
| | - E. Lum
- Division of Nephrology, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - U. Reddy
- Division of Nephrology, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - E. Huang
- Division of Nephrology, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - P.T. Pham
- Division of Nephrology, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - S. Bunnapradist
- Division of Nephrology, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - G. Danovitch
- Division of Nephrology, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - J. Veale
- Department of Urology, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - H.A. Gritsch
- Department of Urology, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - E.F. Reed
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA
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Ghahremani-Ghajar M, Rojas-Bautista V, Lau WL, Pahl M, Hernandez M, Jin A, Reddy U, Chou J, Obi Y, Kalantar-Zadeh K, Rhee CM. Incremental Hemodialysis: The University of California Irvine Experience. Semin Dial 2017; 30:262-269. [PMID: 28295607 PMCID: PMC5677522 DOI: 10.1111/sdi.12591] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Incremental hemodialysis has been examined as a viable hemodialysis regimen for selected end-stage renal disease (ESRD) patients. Preservation of residual kidney function (RKF) has been the driving impetus for this approach given its benefits upon the survival and quality of life of dialysis patients. While clinical practice guidelines recommend an incremental start of dialysis in peritoneal dialysis patients with substantial RKF, there remains little guidance with respect to incremental hemodialysis as an initial renal replacement therapy regimen. Indeed, several large population-based studies suggest that incremental twice-weekly vs. conventional thrice-weekly hemodialysis has favorable impact upon RKF trajectory and survival among patients with adequate renal urea clearance and/or urine output. In this report, we describe a case series of 13 ambulatory incident ESRD patients enrolled in a university-based center's Incremental Hemodialysis Program over the period of January 2015 to August 2016 and followed through December 2016. Among five patients who maintained a twice-weekly hemodialysis schedule vs. eight patients who transitioned to thrice-weekly hemodialysis, we describe and compare patients' longitudinal case-mix, laboratory, and dialysis treatment characteristics over time. The University of California Irvine Experience is the first systemically examined twice-weekly hemodialysis practice in North America. While future studies are needed to refine the optimal approaches and the ideal patient population for implementation of incremental hemodialysis, our case-series serves as a first report of this innovative management strategy among incident ESRD patients with substantial RKF, and a template for implementation of this regimen.
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Affiliation(s)
- Mehrdad Ghahremani-Ghajar
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, California
| | - Vanessa Rojas-Bautista
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, California
| | - Wei-Ling Lau
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, California
| | - Madeleine Pahl
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, California
| | - Miguel Hernandez
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, California
| | - Anna Jin
- Nephrology Section, Veterans Affairs Long Beach Health Care System, Long Beach, California
| | - Uttam Reddy
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, California
| | - Jason Chou
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, California
| | - Yoshitsugu Obi
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, California
| | - Kamyar Kalantar-Zadeh
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, California
- Nephrology Section, Veterans Affairs Long Beach Health Care System, Long Beach, California
| | - Connie M. Rhee
- Division of Nephrology and Hypertension, University of California Irvine School of Medicine, Orange, California
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Laster M, Soohoo M, Hall C, Streja E, Rhee CM, Ravel VA, Reddy U, Norris KC, Salusky IB, Kalantar-Zadeh K. Racial-ethnic disparities in mortality and kidney transplant outcomes among pediatric dialysis patients. Pediatr Nephrol 2017; 32:685-695. [PMID: 27796622 PMCID: PMC5392236 DOI: 10.1007/s00467-016-3530-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 09/05/2016] [Accepted: 09/25/2016] [Indexed: 12/31/2022]
Abstract
BACKGROUND Previous studies in adult hemodialysis patients have shown that African-American and Hispanic patients have a lower risk of mortality in addition to a lower likelihood of kidney transplantation. However, studies of the association between race and outcomes in pediatric dialysis are sparse and often do not examine outcomes in Hispanic children. The objective was to determine if racial-ethnic disparities in mortality and kidney transplantation outcomes exist in pediatric dialysis patients. METHODS This was a retrospective cohort analysis of 2,697 pediatric dialysis patients (aged 0-20 years) from a large national dialysis organization (entry period 2001-2011) of non-Hispanic white, African-American, and Hispanic race-ethnicity. Associations between race-ethnicity with mortality and kidney transplantation outcomes were examined separately using competing risks methods. Logistic regression analyses were used to examine the association between race-ethnicity, with outcomes within 1 year of dialysis initiation. RESULTS Of the 2,697 pediatric patients in this cohort, 895 were African-American, 778 were Hispanic, and 1,024 were non-Hispanic white. After adjusting for baseline demographics, competing risk survival analysis revealed that compared with non-Hispanic whites, African-Americans had a 64 % higher mortality risk (hazards ratio [HR] = 1.64; 95 % CI 1.24-2.17), whereas Hispanics had a 31 % lower mortality risk (HR = 0.69; 95 % CI 0.47-1.01) that did not reach statistical significance. African-Americans also had higher odds of 1-year mortality after starting dialysis (odds ratio [OR] = 2.08; 95 % CI 0.95-4.58), whereas both African-Americans and Hispanics had a lower odds of receiving a transplant within 1 year of starting dialysis (OR = 0.28; 95 % CI 0.19-0.41 and OR = 0.43; 95 % CI 0.31-0.59 respectively). CONCLUSION In contrast to adults, African-American pediatric dialysis patients have worse survival than their non-Hispanic white counterparts, whereas Hispanics have a similar to lower mortality risk. Both African-American and Hispanic pediatric dialysis patients had a lower likelihood of kidney transplantation than non-Hispanic whites, similar to observations in the adult dialysis population.
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Affiliation(s)
- Marciana Laster
- David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Melissa Soohoo
- Harold Simmons Center for Kidney Disease Research and Epidemiology, Division of Nephrology and Hypertension, School of Medicine, University of California Irvine, 101 The City Drive South, City Tower, Suite 400, ZOT: 4088, Orange, CA, 92868-3217, USA
| | - Clinton Hall
- Department of Epidemiology, UCLA Fielding School of Public Health, Los Angeles, CA, USA
| | - Elani Streja
- Harold Simmons Center for Kidney Disease Research and Epidemiology, Division of Nephrology and Hypertension, School of Medicine, University of California Irvine, 101 The City Drive South, City Tower, Suite 400, ZOT: 4088, Orange, CA, 92868-3217, USA
| | - Connie M Rhee
- Harold Simmons Center for Kidney Disease Research and Epidemiology, Division of Nephrology and Hypertension, School of Medicine, University of California Irvine, 101 The City Drive South, City Tower, Suite 400, ZOT: 4088, Orange, CA, 92868-3217, USA
- Division of Nephrology and Hypertension, School of Medicine, University of California Irvine, Orange, CA, USA
| | - Vanessa A Ravel
- Harold Simmons Center for Kidney Disease Research and Epidemiology, Division of Nephrology and Hypertension, School of Medicine, University of California Irvine, 101 The City Drive South, City Tower, Suite 400, ZOT: 4088, Orange, CA, 92868-3217, USA
| | - Uttam Reddy
- Division of Nephrology and Hypertension, School of Medicine, University of California Irvine, Orange, CA, USA
| | - Keith C Norris
- David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | | | - Kamyar Kalantar-Zadeh
- David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
- Harold Simmons Center for Kidney Disease Research and Epidemiology, Division of Nephrology and Hypertension, School of Medicine, University of California Irvine, 101 The City Drive South, City Tower, Suite 400, ZOT: 4088, Orange, CA, 92868-3217, USA.
- Division of Nephrology and Hypertension, School of Medicine, University of California Irvine, Orange, CA, USA.
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Wang M, Chou J, Chang Y, Lau WL, Reddy U, Rhee CM, Chen J, Hao C, Kalantar-Zadeh K. The role of low protein diet in ameliorating proteinuria and deferring dialysis initiation: what is old and what is new. Panminerva Med 2016; 59:157-165. [PMID: 27759735 DOI: 10.23736/s0031-0808.16.03264-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In the management of patients with chronic kidney diseases (CKD), a low-protein diet usually refers to a diet with protein intake of 0.6 to 0.8 grams per kilogram of body weight per day (g/kg/day) and should include at least 50% high-biologic-value protein. It may be supplemented with essential acids or nitrogen-free ketoanalogues if <0.6 g/kg/d. Low-protein diet can reduce proteinuria especially in non-diabetic CKD patients. In hypoalbuminemic patients it may lead to an increase in serum albumin level. By lowering proteinuria, decreasing nitrogen waste products, ameliorating metabolic burden, mitigating oxidative stress and acidosis, and lowering phosphorus burden, a low-protein diet can help delay dialysis start in advanced CKD. Low-protein diet is safe, since most CKD patients can maintain nitrogen balance by mechanisms of decreasing amino acid oxidation and protein degradation in addition to increased utilization of amino acids for protein synthesis. We suggest a dietary protein intake below 1.0 g/kg/day when estimated glomerular filtration rate (eGFR) falls below 60 mL/min/1.73 m2 or when there is solitary kidney or proteinuria at any level of GFR. Protein intake should be reduced progressively based on severity and progression of CKD and patient's nutritional status with a target of 0.6-0.8 g/kg/d in most patients with eGFR <45 mL/min/1.73 m2. The risk of protein-energy wasting can be overcome by careful attention to quantity and quality of the ingested proteins, sufficient energy intake of 30-35 Kcal/kg/d, and use of dietary supplements. Long-term observations and individualized approaches are needed to further demonstrate the benefits and safety of low-protein diet.
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Affiliation(s)
- Mengjing Wang
- Division of Nephrology and Hypertension, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine Medical Center, Orange, CA, USA.,Division of Nephrology, Fudan University, Huashan Hospital, Shanghai, China
| | - Jason Chou
- Division of Nephrology and Hypertension, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine Medical Center, Orange, CA, USA
| | - Yongen Chang
- Division of Nephrology and Hypertension, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine Medical Center, Orange, CA, USA
| | - Wei L Lau
- Division of Nephrology and Hypertension, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine Medical Center, Orange, CA, USA
| | - Uttam Reddy
- Division of Nephrology and Hypertension, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine Medical Center, Orange, CA, USA
| | - Connie M Rhee
- Division of Nephrology and Hypertension, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine Medical Center, Orange, CA, USA
| | - Jing Chen
- Division of Nephrology, Fudan University, Huashan Hospital, Shanghai, China
| | - Chuanming Hao
- Division of Nephrology, Fudan University, Huashan Hospital, Shanghai, China
| | - Kamyar Kalantar-Zadeh
- Division of Nephrology and Hypertension, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine Medical Center, Orange, CA, USA - .,Department of Epidemiology, UCLA Fielding School of Public Health, Los Angeles, CA, USA
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Abstract
Complete situs inversus is a rare congenital anomaly characterized by transposition of organs. We report a case of renal transplantation using a kidney from a living complete situs inversus donor. The recipient was a 59-year-old female with end-stage renal disease because of type 2 diabetes mellitus. The donor was the 56-year-old sister of the recipient with complete situs inversus. CT angiogram of the abdomen and pelvis showed complete situs inversus and an otherwise normal appearance of the bilateral kidneys with patent bilateral single renal arteries and longer renal vein in the right kidney. The patient was taken to the operating room for a hand-assisted laparoscopic right donor nephrectomy. The patient tolerated the procedure well and was discharged home in good condition on postoperative day 1. The recipient experienced no episodes of acute rejection or infection, with serum creatinine levels of 0.8–1.2 mg/dL. Laparoscopic donor nephrectomy in a patient with complete situs inversus remains a technically feasible operation and the presence of situs inversus should not preclude consideration for living kidney donation.
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Affiliation(s)
- John V Gahagan
- Department of Surgery, University of California , Irvine School of Medicine, Orange, California
| | - Matthew D Whealon
- Department of Surgery, University of California , Irvine School of Medicine, Orange, California
| | - Uttam Reddy
- Department of Medicine, University of California , Irvine School of Medicine, Orange, California
| | - Clarence E Foster
- Department of Surgery, University of California , Irvine School of Medicine, Orange, California
| | - Hirohito Ichii
- Department of Surgery, University of California , Irvine School of Medicine, Orange, California
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Lan JH, Zhang Q, Reed EF, Reddy U. OR19 Successful reversal of severe kidney allograft rejection mediated by angiotensin II type 1-receptor antibodies. Hum Immunol 2015. [DOI: 10.1016/j.humimm.2015.07.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Ahmadi SF, Streja E, Zahmatkesh G, Streja D, Kashyap M, Moradi H, Molnar MZ, Reddy U, Amin AN, Kovesdy CP, Kalantar-Zadeh K. Reverse Epidemiology of Traditional Cardiovascular Risk Factors in the Geriatric Population. J Am Med Dir Assoc 2015; 16:933-9. [PMID: 26363864 DOI: 10.1016/j.jamda.2015.07.014] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 07/21/2015] [Indexed: 01/08/2023]
Abstract
Traditional risk factors of cardiovascular death in the general population, including body mass index (BMI), serum cholesterol, and blood pressure (BP), are also found to relate to outcomes in the geriatric population, but in an opposite direction. Some degrees of elevated BMI, serum cholesterols, and BP are reportedly associated with lower, instead of higher, risk of death among the elderly. This phenomenon is termed "reverse epidemiology" or "risk factor paradox" (such as obesity paradox) and is also observed in a variety of chronic disease states such as end-stage renal disease requiring dialysis, chronic heart failure, rheumatoid arthritis, and AIDS. Several possible causes are hypothesized to explain this risk factor reversal: competing short-term and long-term killers, improved hemodynamic stability in the obese, adipokine protection against tumor necrosis factor-α, lipoprotein protection against endotoxins, and lipophilic toxin sequestration by the adipose tissue. It is possible that the current thresholds for intervention and goal levels for such traditional risk factors as BMI, serum cholesterol, and BP derived based on younger populations do not apply to the elderly, and that new levels for such risk factors should be developed for the elderly population. Reverse epidemiology of conventional cardiovascular risk factors may have a bearing on the management of the geriatric population, thus it deserves further attention.
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Affiliation(s)
- Seyed-Foad Ahmadi
- Division of Nephrology and Hypertension, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine Medical Center, Orange, CA; Department of Population Health and Disease Prevention, Program in Public Health, University of California Irvine, Irvine, CA
| | - Elani Streja
- Division of Nephrology and Hypertension, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine Medical Center, Orange, CA; Nephrology Section, Department of Medicine, Veterans Affairs Long Beach Healthcare System, Long Beach, CA
| | - Golara Zahmatkesh
- Division of Nephrology and Hypertension, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine Medical Center, Orange, CA
| | - Dan Streja
- Department of Medicine, Providence Medical Institute, West Hills, CA
| | - Moti Kashyap
- Nephrology Section, Department of Medicine, Veterans Affairs Long Beach Healthcare System, Long Beach, CA
| | - Hamid Moradi
- Division of Nephrology and Hypertension, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine Medical Center, Orange, CA
| | - Miklos Z Molnar
- Division of Nephrology, University of Tennessee Health Science Center, Memphis, TN
| | - Uttam Reddy
- Division of Nephrology and Hypertension, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine Medical Center, Orange, CA
| | - Alpesh N Amin
- Department of Medicine, University of California Irvine Medical Center, Orange, CA
| | - Csaba P Kovesdy
- Division of Nephrology, University of Tennessee Health Science Center, Memphis, TN; Memphis Veterans Affairs Medical Center, Memphis, TN
| | - Kamyar Kalantar-Zadeh
- Division of Nephrology and Hypertension, Harold Simmons Center for Kidney Disease Research and Epidemiology, University of California Irvine Medical Center, Orange, CA; Department of Population Health and Disease Prevention, Program in Public Health, University of California Irvine, Irvine, CA; Nephrology Section, Department of Medicine, Veterans Affairs Long Beach Healthcare System, Long Beach, CA; Department of Epidemiology, UCLA School of Public Health, Los Angeles, CA.
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Mendola P, Laughon S, Männistö T, Zhang J, Leishear K, Reddy U, Chen Z. Pregnancy Complications Associated With Asthma. Ann Epidemiol 2012. [DOI: 10.1016/j.annepidem.2012.06.077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Spillane J, Hirsch N, Kullmann D, Reddy U, Taylor C, Howard R. P32 Myasthenic crisis in the intensive care unit – a ten year review. Neuromuscul Disord 2011. [DOI: 10.1016/s0960-8966(11)70051-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Gulla S, Waghray K, Reddy U. Blending of Oils-Does it Improve the Quality and Storage Stability, an Experimental Approach on Soyabean and Palmolein Based Blends. ACTA ACUST UNITED AC 2010. [DOI: 10.3923/ajft.2010.182.194] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Abstract
The phenomenon of stillbirth has been poorly addressed in terms of reported statistics and as a clinical issue. A Study Group of the European Association of Perinatal Medicine reviewed the topic and highlighted specific issues. Such proposal was discussed in an open workshop held in Modena, Italy last year and this paper reports the final recommendations. Briefly, at least 22 completed weeks of gestation was endorsed as definition for including SB in statistics and for clinical studies. A minimum diagnostic work-up was suggested together with the emphasis toward a local, multidisciplinary audit process, in order to comprehend causality. Attention for parents emotional support and appropriate counselling was believed as essential part of the clinical process. Finally, the need for funding comprehensive research programs in SB through international, multidisciplinary involvement was believed mandatory for developing effective preventative strategies to avert the devastating occurrence of stillbirth.
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Affiliation(s)
- F Facchinetti
- Mother-Infant Department, Unit of Obstetrics and Gynecology, University of Modena and Reggio Emilia, Modena, Italy.
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Porkert M, Sher S, Reddy U, Cheema F, Niessner C, Kolm P, Jones DP, Hooper C, Taylor WR, Harrison D, Quyyumi AA. Tetrahydrobiopterin: a novel antihypertensive therapy. J Hum Hypertens 2008; 22:401-7. [PMID: 18322548 DOI: 10.1038/sj.jhh.1002329] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2007] [Revised: 11/21/2007] [Accepted: 12/01/2007] [Indexed: 11/09/2022]
Abstract
Tetrahydrobiopterin (BH(4)) is a cofactor for the nitric oxide (NO) synthase enzymes, such that its insufficiency results in uncoupling of the enzyme, leading to release of superoxide rather than NO in disease states, including hypertension. We hypothesized that oral BH(4) will reduce arterial blood pressure (BP) and improve endothelial function in hypertensive subjects. Oral BH(4) was given to subjects with poorly controlled hypertension (BP >135/85 mm Hg) and weekly measurements of BP and endothelial function made. In Study 1, 5 or 10 mg kg(-1) day(-1) of BH(4) (n=8) was administered orally for 8 weeks, and in Study 2, 200 and 400 mg of BH(4) (n=16) was given in divided doses for 4 weeks. Study 1: significant reductions in systolic (P=0.005) and mean BP (P=0.01) were observed with both doses of BH(4). Systolic BP was 15+/-15 mm Hg (P=0.04) lower after 5 weeks and persisted for the 8-week study period. Study 2: subjects given 400 mg BH(4) had decreased systolic (P=0.03) and mean BP (P=0.04), with a peak decline of 16+/-19 mm Hg (P=0.04) at 3 weeks. BP returned to baseline 4 weeks after discontinuation. Significant improvement in endothelial function was observed in Study 1 subjects and those receiving 400 mg BH(4). There was no significant change in subjects given the 200 mg dose. This pilot investigation indicates that oral BH(4) at a daily dose of 400 mg or higher has a significant and sustained antihypertensive effect in subjects with poorly controlled hypertension, an effect that is associated with improved endothelial NO bioavailability.
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Affiliation(s)
- M Porkert
- Division of Cardiology, Emory University, Atlanta, GA, USA
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Abstract
BACKGROUND Endothelial dysfunction assessed by brachial artery flow-mediated dilation (FMD) is a marker for early atherosclerotic vascular disease and future cardiovascular events. OBJECTIVE To estimate the heritability of brachial artery FMD using a twin design. METHODS We estimated the heritability of FMD using 94 middle-aged male twin pairs. FMD was measured by ultrasound, and traditional coronary heart disease risk factors were measured. Genetic modeling techniques were used to determine the relative contributions of genes and environment to the variation in FMD. RESULTS The mean age of the twin participants was 54.9 +/- 2.8 years. The mean FMD was 0.047 +/- 0.030. The intraclass correlation coefficient was higher in MZ twins [0.38, 95% confidence interval (CI) 0.32-0.43] than in DZ twins (0.19, 95% CI 0.11-0.26), suggesting a role of genetic influence in FMD variation. Structural equation modeling showed that both genetic and unique environmental factors contributed significantly to the variation in FMD. The crude FMD heritability was 0.37 (95% CI 0.15-0.54). After adjustment for traditional cardiovascular risk factors, including age, total cholesterol, blood pressure, and body mass index, the heritability of FMD was 39% (95% CI 0.18-0.56). The remaining variation in FMD could be explained by individual-specific environment. CONCLUSION This is the first study using twins to estimate the relative contributions of genetics and environment to the variation in FMD in a US population. Our results demonstrate a moderate genetic effect on brachial artery FMD, independent of traditional coronary risk factors. Our data also highlight the importance of unique environment on the variability in FMD.
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Affiliation(s)
- J Zhao
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, 1256 Briarcliff Road NE, Atlanta, GA 30306, USA
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Abstract
BACKGROUND Antiangiogenic therapy is a new approach to the treatment of neovascular age-related macular degeneration. Interferon alfa is one antiangiogenic agent thought to function by inhibiting the migration and proliferation of vascular endothelial cells. It has been used in the treatment of hepatitis, solid tumors and hematologic malignancies. OBJECTIVES The aim of this review was to investigate interferon alfa as a treatment modality for neovascular age-related macular degeneration. SEARCH STRATEGY We searched and identified trials from the Cochrane Central Register of Controlled Trials (CENTRAL), which contains the Cochrane Eyes and Vision Group Trials Register, in The Cochrane Library (Issue 2, 2005), MEDLINE (1966 to 2005/06 week 1), EMBASE (1980 to 2005/week 23), LILACS (Latin American and Caribbean Health Science Literature Database) (June 2005) and the reference lists of included studies. SELECTION CRITERIA This review included randomized controlled trials evaluating interferon alfa therapy in people with neovascular age-related macular degeneration who were followed for at least one year. DATA COLLECTION AND ANALYSIS Both review authors independently extracted data and assessed trial quality. No data synthesis was conducted as only one trial met the inclusion criteria. MAIN RESULTS The one included trial enrolled and randomized 481 participants from 45 centers worldwide into four groups. The study allowed for analysis of the number of participants who had lost three or more lines of vision at 52 weeks in three interferon alfa-2a groups versus placebo. The results show an odds ratio of 1.60 (95% Confidence Interval 1.01 to 2.53) indicating that interferon is associated with a 60% increased odds of losing three or more lines at 52 weeks. This finding is marginally statistical with a P value of 0.04 and indicates that the treatment has the potential for harm rather than benefit. AUTHORS' CONCLUSIONS At present there is not enough evidence to recommend the use of interferon alfa-2a for the treatment of age-related macular degeneration.
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Affiliation(s)
- U Reddy
- Brown Medical School, Box G-8064, 593 Eddy Street, Providence, Rhode Island 02903, USA.
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Vaccarino V, Goldberg J, Cheema F, Reddy U, Maisano C, Jones L, Murrah N, Quyyumi A, Bremner J. We-W39:5 Flow-mediated vasodilation predicts occult coronary artery disease detected by positron emission tomography. ATHEROSCLEROSIS SUPP 2006. [DOI: 10.1016/s1567-5688(06)81292-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Odibo AO, Berghella V, Reddy U, Tolosa JE, Wapner RJ. Does transvaginal ultrasound of the cervix predict preterm premature rupture of membranes in a high-risk population? Ultrasound Obstet Gynecol 2001; 18:223-227. [PMID: 11555450 DOI: 10.1046/j.1469-0705.2001.00419.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
OBJECTIVES To determine in patients with a cervical length < 25 mm on transvaginal ultrasound if the severity of cervical length shortening can be used to predict preterm premature rupture of membranes (PPROM) and the contribution of PPROM to preterm delivery in these patients. METHODS We retrospectively reviewed asymptomatic singleton pregnancies between 14 and 24 weeks at high risk of preterm delivery by obstetric history and transvaginal cervical length < 25 mm. Cases developing subsequent PPROM were compared with controls for transvaginal sonographic cervical characteristics. RESULTS Of 69 patients identified to have a cervical length < 25 mm, 27 (39%) had PPROM, and 42 (61%) did not. Mean +/- standard deviation (SD) cervical length was 12.7 +/- 8.7 mm and 17.0 +/- 7.6 mm in the two groups, respectively (P = 0.04). Mean +/- SD cervical funneling was 57.4 +/- 31.4% and 40.0 +/- 28.1%, respectively (P = 0.01). The characteristics most predictive of PPROM were: cervical length of < 10 mm (sensitivity, specificity, positive and negative predictive values of 33, 90, 69, and 68%, respectively; odds ratio, 4.8; 95% confidence interval, 1.3-17.5) and cervical funneling > 75% (sensitivity, specificity, positive and negative predictive values of 33, 93, 75 and 68%, respectively; odds ratio, 6.5; 95% confidence interval, 1.6-26.9). Stepwise logistic regression revealed cervical length to be a significant predictor of PPROM (odds ratio, 4.0; 95% confidence interval, 1.1-14.2). CONCLUSION In patients at high risk for preterm delivery because of obstetric history and transvaginal sonographic cervical length < 25 mm, a cervical length < 10 mm and cervical funneling > 75% were most predictive of PPROM. PPROM was the major contributor to preterm delivery in these patients.
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Affiliation(s)
- A O Odibo
- Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Jefferson Medical College of the Thomas Jefferson University, Philadelphia, PA 19107, USA.
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Thadepalli H, Reddy U, Chuah SK, Hanna N, Rana G, Gollapudi S. Evaluation of trovafloxacin in the treatment of Klebsiella pneumoniae lung infection in tumour-bearing mice. J Antimicrob Chemother 2000; 45:69-75. [PMID: 10629015 DOI: 10.1093/jac/45.1.69] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Trovafloxacin, a new trifluoroquinolone, was evaluated for its therapeutic efficacy against Klebsiella pneumoniae lung infection in tumour (P388 murine leukaemia cells)-bearing mice, treated with or without a chemotherapeutic agent, daunorubicin (DNR) and in mice without tumour. Its activity was compared with ciprofloxacin and cephazolin. The effect on therapeutic efficacy of the addition of recombinant granulocyte colony stimulating factor (rGCSF) was also examined. Our study showed that both quinolones successfully cured pneumonia owing to infection with K. pneumoniae in mice without tumours but that all antibiotics failed in tumour-bearing mice if DNR was withheld. Substantial differences were noted in DNR-treated tumour-bearing mice with infection-the cure rate with trovafloxacin was 91% whereas the cure rate with ciprofloxacin or cephazolin was 57%. Addition of rGCSF to ciprofloxacin did not substantially improve its efficacy (when assessed by protection against death owing to infection; the survival rate was 41%). Trovafloxacin cure rates ranged from 80 to 90% whether or not rGCSF was added to the treatment regimen. Our results suggest that prior cancer chemotherapy had no adverse effect on the therapeutic efficacy of trovafloxacin, and that trovafloxacin may be a promising therapeutic agent for treatment of bacterial infections in the presence of leucopenia.
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Affiliation(s)
- H Thadepalli
- Department of Medicine and Pathology, Charles R. Drew University of Medicine and Sciences, 1731 East 120th Street, Los Angeles, CA 90059, USA.
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Thadepalli H, Chuah SK, Reddy U, Hanna N, Clark R, Polzer RJ, Gollapudi S. Efficacy of trovafloxacin for treatment of experimental Bacteroides infection in young and senescent mice. Antimicrob Agents Chemother 1997; 41:1933-6. [PMID: 9303387 PMCID: PMC164038 DOI: 10.1128/aac.41.9.1933] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
We investigated the efficacy of trovafloxacin, a new quinolone, in comparison with that of clindamycin in the treatment of intra-abdominal abscesses caused by Bacteroides fragilis in young and senescent mice. The development of abscess formation, the number of viable organisms, and antibiotic concentrations were measured, and the values for young and old mice were compared. Trovafloxacin was well distributed to the tissues in both young and old animals. Although the pharmacokinetics and concentrations of trovafloxacin in serum were similar between young and old mice, the levels in tissue were higher in senescent mice than in young mice. Trovafloxacin therapy sterilized abscesses in 94% of young mice and in 73% of old mice, but this difference was not significant. This therapeutic response to trovafloxacin was similar to that seen with clindamycin. These results suggest that aging may not have any adverse effect on the therapeutic outcome for intra-abdominal abscesses caused by B. fragilis.
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Affiliation(s)
- H Thadepalli
- Division of Geriatrics and Gerontology, Charles R. Drew University of Medicine and Science, Los Angeles, California 90059, USA
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Thadepalli H, Reddy U, Chuah SK, Thadepalli F, Malilay C, Polzer RJ, Hanna N, Esfandiari A, Brown P, Gollapudi S. In vivo efficacy of trovafloxacin (CP-99,217), a new quinolone, in experimental intra-abdominal abscesses caused by Bacteroides fragilis and Escherichia coli. Antimicrob Agents Chemother 1997; 41:583-6. [PMID: 9055997 PMCID: PMC163755 DOI: 10.1128/aac.41.3.583] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The efficacy of trovafloxacin in treating Bacteroides fragilis and Escherichia coli infections was investigated and compared to the efficacy of combined clindamycin and gentamicin therapy in an experimental model of intra-abdominal abscesses in rats. Rats were treated with different doses of CP-116,517-27, a parenteral prodrug of trovafloxacin. Response to treatment was evaluated by mortality rate and elimination of infection (cure rate). Mortality in the control group was 85.4%, whereas in rats treated with trovafloxacin, it was close to 0%. The highest cure rate (89.3%) resulted from the administration of 40 mg of CP-116,517-27 per kg of body weight three times a day (TID) for 10 days (equivalent to 18.15 mg of active drug trovafloxacin per rat per day). The therapeutic response with trovafloxacin was comparable to that of a combination therapy of clindamycin (75 mg/kg) plus gentamicin (20 mg/kg) TID (cure rate, 74%; mortality rate, 5%). The measured peak levels of trovafloxacin in serum and abscess pus were 2.6 +/- 0.3 and 5.2 micrograms/ml, respectively. The tumor necrosis factor alpha levels in the untreated animals were high compared to those for rats treated with trovafloxacin or clindamycin plus gentamicin. These results demonstrate that trovafloxacin as a single agent appears to be as successful as clindamycin plus gentamicin in the treatment of experimental intra-abdominal abscesses in rats.
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Affiliation(s)
- H Thadepalli
- Department of Medicine, Charles R. Drew University of Medicine and Science, Los Angeles, California 90059, USA
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Rakowicz-Szulczynska EM, Reddy U, Vorbrodt A, Herlyn D, Koprowski H. Chromatin and cell surface receptors mediate melanoma cell growth response to nerve growth factor. Mol Carcinog 1991; 4:388-96. [PMID: 1654924 DOI: 10.1002/mc.2940040511] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Growth response to nerve growth factor (NGF) was tested in the primary melanoma cell line WM 164, which expressed a low level of NGF cell-surface receptor, and in WM 164 cells transfected with cDNA for the cell-surface receptor (TrWM 164 cells), which expressed a higher level of the cell-surface receptor. Neither cell line expressed the chromatin receptor for NGF or internalized NGF. Both cell lines were stimulated to growth by NGF. After 10 d of exposure to NGF, a 230,000 Mr chromatin protein (receptor) was induced in both cell lines; as a result, NGF bound to the chromatin, and ribosomal RNA synthesis and cell proliferation were inhibited. We suggest that the cell-surface and chromatin receptors each mediate a different function of NGF.
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Beattie DS, Scotto AW, Reddy U, DeLoskey R, Bosch CG. Pyridoxal phosphate protects against an irreversible temperature-dependent inactivation of hepatic delta-aminolevulinic acid synthase. Arch Biochem Biophys 1985; 236:311-20. [PMID: 3966797 DOI: 10.1016/0003-9861(85)90631-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The stability of hepatic delta-aminolevulinic acid synthase (ALAS), the first and rate-limiting enzyme of the heme biosynthetic pathway, was investigated. Incubation of the mitochondrial matrix fraction obtained from either control or allylisopropylacetamide-induced rats at 37 degrees C in Tris-Cl, pH 7.4, EDTA, and dithiothreitol resulted in a rapid decrease in ALAS activity such that 50-70% of the activity was lost after 30 min. Similar decreases in ALAS activity were observed when a cytosolic fraction from the induced animals was incubated at 37 degrees C. Addition of 0.1 mM pyridoxal-P, the cofactor of ALAS, to the preincubation medium completely prevented the observed loss of activity; however, dialysis of the inactive matrix fraction against several changes of buffer containing pyridoxal-P did not restore activity, suggesting that the inactivation was irreversible. These decreases in ALAS activity in the absence of pyridoxal-P were temperature dependent, as a 55% loss of ALAS activity was observed after a 60-min incubation at 30 degrees C, while the enzyme was completely stable when preincubated at 22 degrees C for 60 min. This inactivation of ALAS does not appear to involve proteolytic digestion, as addition of a wide spectrum of protease inhibitors to the preincubation medium in the absence of pyridoxal-P did not protect against the inactivation. The suggestion is made that the cofactor, pyridoxal-P, may dissociate from the enzyme during the preincubation and, consequently, the apoenzyme may be irreversibly inactivated at temperatures above 22 degrees C.
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