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Sikaneta T, Ho N, Bellasi A, Mahdavi S, Taskapan H, Svendrovski A, Makanjee B, Roberts J, Wu G, Nathoo B, Tam P. QTc Interval Prolongation Is Independently Associated with FGF23 and Predicts Mortality in Predialysis Chronic Kidney Disease. Cardiorenal Med 2024; 14:45-57. [PMID: 37963445 DOI: 10.1159/000535133] [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] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 10/24/2023] [Indexed: 11/16/2023] Open
Abstract
INTRODUCTION QTc interval prolongation is increasingly frequent as chronic kidney disease (CKD) advances and predicts death in dialysis. However, predictors and mortality risk in predialysis CKD are understudied. FGF23 induces left ventricular hypertrophy (LVH) which is associated with QTc interval prolongation and death, suggesting a possible pathway from FGF23 to death that entails LVH and QTc prolongation. We looked for links between FGF23 and prolonged QTc intervals mediated by LVH and for deaths associated with QTc prolongation in a prospective observational cohort of patients with predialysis CKD. METHODS Participants underwent protocolized baseline and semiannual FGF23 testing, baseline and study end echocardiograms, and baseline and annual electrocardiograms over 3 years. RESULTS A total of 2,254 participants (34.1% female; mean age: 68.7 years; mean glomerular filtration: rate 41.4 mL/min/m2) enrolled in the study. Baseline LVH (left ventricular mass index >131 g/m2 [>100 g/m2 if female]) was present in 10.8% and prolonged QTc intervals (≥500 ms) in 1.5% of participants. One hundred thirty-eight (6.1%) participants died during the study. In generalized mixed-effects regression, each unit increase in the natural log of FGF23 - but not LVH - predicted an odds ratio of 1.76 (1.15, 2.70, p = 0.009) for prolonged QTc intervals independently of 15 other covariates. Mediation analysis showed that only 13% of FGF23's total effect on prolonged QTc intervals was mediated by LVH. Patients with prolonged QTc intervals had higher unadjusted (log rank p < 0.001) and adjusted (hazard ratio: 2.06 [1.08, 3.92, p = 0.028]) mortality rates than those with QTc intervals <500 ms. DISCUSSION QTc interval prolongation ≥500 ms was prospectively associated with FGF23 independently of LVH and with increased mortality risk in patients with predialysis CKD.
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Affiliation(s)
- Tabo Sikaneta
- Department of Nephrology, The Scarborough Health Network, Toronto, Ontario, Canada
- Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
- Kidney Life Sciences Institute, Toronto, Ontario, Canada
| | - Natalie Ho
- Department of Cardiology, The Scarborough Health Network, Toronto, Ontario, Canada
| | - Antonio Bellasi
- Division of Nephrology, Department of Medicine, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | - Sara Mahdavi
- Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Hulya Taskapan
- Kidney Life Sciences Institute, Toronto, Ontario, Canada
| | | | | | - Jason Roberts
- Population Health Research Institute, Hamilton, Ontario, Canada
| | - George Wu
- Credit Valley Hospital, Mississauga, Ontario, Canada
| | | | - Paul Tam
- Department of Nephrology, The Scarborough Health Network, Toronto, Ontario, Canada
- Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
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Cowan AC, Clemens KK, Sontrop JM, Dixon SN, Killin L, Anderson S, Acedillo RR, Bagga A, Bohm C, Brown PA, Cote B, Dev V, Harris C, Hiremath S, Kiaii M, Lacson E, Molnar AO, Oliver MJ, Parmar MS, McRae JM, Nathoo B, Quinn K, Shah N, Silver SA, Tascona DJ, Thompson S, Ting RH, Tonelli M, Vorster H, Wadehra DB, Wald R, Wolf M, Garg AX. Magnesium and Fracture Risk in the General Population and Patients Receiving Dialysis: A Narrative Review. Can J Kidney Health Dis 2023; 10:20543581231154183. [PMID: 36814964 PMCID: PMC9940170 DOI: 10.1177/20543581231154183] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 12/18/2022] [Indexed: 02/19/2023] Open
Abstract
Purpose of Review Magnesium is an essential mineral for bone metabolism, but little is known about how magnesium intake alters fracture risk. We conducted a narrative review to better understand how magnesium intake, through supplementation, diet, or altering the concentration of dialysate magnesium, affects mineral bone disease and the risk of fracture in individuals across the spectrum of kidney disease. Sources of Information Peer-reviewed clinical trials and observational studies. Methods We searched for relevant articles in MEDLINE and EMBASE databases. The methodologic quality of clinical trials was assessed using a modified version of the Downs and Black criteria checklist. Key Findings The role of magnesium intake in fracture prevention is unclear in both the general population and in patients receiving maintenance dialysis. In those with normal kidney function, 2 meta-analyses showed higher bone mineral density in those with higher dietary magnesium, whereas 1 systematic review showed no effect on fracture risk. In patients receiving maintenance hemodialysis or peritoneal dialysis, a higher concentration of dialysate magnesium is associated with a lower concentration of parathyroid hormone, but little is known about other bone-related outcomes. In 2 observational studies of patients receiving hemodialysis, a higher concentration of serum magnesium was associated with a lower risk of hip fracture. Limitations This narrative review included only articles written in English. Observed effects of magnesium intake in the general population may not be applicable to those with chronic kidney disease particularly in those receiving dialysis.
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Affiliation(s)
- Andrea C. Cowan
- Division of Nephrology, Department of Medicine, Victoria Hospital, London Health Sciences Centre, ON, Canada,Andrea C. Cowan, Division of Nephrology, Department of Medicine, Victoria Hospital, London Health Sciences Centre, 800 Commissioners Road, Room ELL-215, London, ON N6A 5W9, Canada.
| | - Kristin K. Clemens
- Division of Endocrinology, Department of Medicine, St. Joseph’s Hospital, London, ON, Canada
| | - Jessica M. Sontrop
- Department of Epidemiology and Biostatistics, Western University, London, ON, Canada
| | - Stephanie N. Dixon
- Department of Epidemiology and Biostatistics, Western University, London, ON, Canada,Lawson Health Research Institute, London Health Sciences Centre, ON, Canada
| | | | | | - Rey R. Acedillo
- Department of Medicine, Thunder Bay Regional Health Sciences Centre, ON, Canada
| | | | - Clara Bohm
- Chronic Disease Innovation Centre, Winnipeg, MB, Canada,University of Manitoba, Winnipeg, Canada
| | - Pierre Antoine Brown
- Department of Medicine, The Ottawa Hospital Research Institute, University of Ottawa, ON, Canada
| | - Brenden Cote
- Patient Partner, London Health Sciences Centre, ON, Canada
| | - Varun Dev
- Humber River Hospital, Toronto, ON, Canada
| | - Claire Harris
- Division of Nephrology, Department of Medicine, Vancouver General Hospital, The University of British Columbia, Canada
| | | | - Mercedeh Kiaii
- Division of Nephrology, Department of Medicine, St. Paul’s Hospital, Vancouver, BC, Canada
| | - Eduardo Lacson
- Division of Nephrology, Tufts University School of Medicine, Boston, MA, USA
| | - Amber O. Molnar
- Department of Medicine, St Joseph’s Healthcare Hamilton, ON, Canada
| | - Matthew J. Oliver
- Division of Nephrology, Department of Medicine, Sunnybrook Health Sciences Centre, University of Toronto, ON, Canada
| | | | - Jennifer M. McRae
- Division of Nephrology, Department of Medicine, University of Calgary, AB, Canada
| | | | | | | | - Samuel A. Silver
- Division of Nephrology, Kingston Health Sciences Center, Queen’s University, ON, Canada
| | | | | | | | | | | | | | - Ron Wald
- Division of Nephrology, St. Michael’s Hospital, University of Toronto, ON, Canada
| | - Myles Wolf
- Division of Nephrology, Department of Medicine, Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC, USA
| | - Amit X. Garg
- Division of Nephrology, Department of Medicine, Victoria Hospital, London Health Sciences Centre, ON, Canada
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Al-Jaishi AA, McIntyre CW, Sontrop JM, Dixon SN, Anderson S, Bagga A, Benjamin D, Berry D, Blake PG, Chambers L, Chan PCK, Delbrouck N, Devereaux PJ, Ferreira-Divino LF, Goluch R, Gregor L, Grimshaw JM, Hanson G, Iliescu E, Jain AK, Lok CE, Mustafa RA, Nathoo B, Nesrallah GE, Oliver MJ, Pandeya S, Parmar MS, Perkins D, Presseau J, Rabin E, Sasal J, Shulman T, Sood MM, Steele A, Tam P, Tascona D, Wadehra D, Wald R, Walsh M, Watson P, Wodchis W, Zager P, Zwarenstein M, Garg AX. Major Outcomes With Personalized Dialysate TEMPerature (MyTEMP): Rationale and Design of a Pragmatic, Registry-Based, Cluster Randomized Controlled Trial. Can J Kidney Health Dis 2020; 7:2054358119887988. [PMID: 32076569 PMCID: PMC7003172 DOI: 10.1177/2054358119887988] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 09/23/2019] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND Small randomized trials demonstrated that a lower compared with higher dialysate temperature reduced the average drop in intradialytic blood pressure. Some observational studies demonstrated that a lower compared with higher dialysate temperature was associated with a lower risk of all-cause mortality and cardiovascular mortality. There is now the need for a large randomized trial that compares the effect of a low vs high dialysate temperature on major cardiovascular outcomes. OBJECTIVE The purpose of this study is to test the effect of outpatient hemodialysis centers randomized to (1) a personalized temperature-reduced dialysate protocol or (2) a standard-temperature dialysate protocol for 4 years on cardiovascular-related death and hospitalizations. DESIGN The design of the study is a pragmatic, registry-based, open-label, cluster randomized controlled trial. SETTING Hemodialysis centers in Ontario, Canada, were randomized on February 1, 2017, for a trial start date of April 3, 2017, and end date of March 31, 2021. PARTICIPANTS In total, 84 hemodialysis centers will care for approximately 15 500 patients and provide over 4 million dialysis sessions over a 4-year follow-up. INTERVENTION Hemodialysis centers were randomized (1:1) to provide (1) a personalized temperature-reduced dialysate protocol or (2) a standard-temperature dialysate protocol of 36.5°C. For the personalized protocol, nurses set the dialysate temperature between 0.5°C and 0.9°C below the patient's predialysis body temperature for each dialysis session, to a minimum dialysate temperature of 35.5°C. PRIMARY OUTCOME A composite of cardiovascular-related death or major cardiovascular-related hospitalization (a hospital admission with myocardial infarction, congestive heart failure, or ischemic stroke) captured in Ontario health care administrative databases. PLANNED PRIMARY ANALYSIS The primary analysis will follow an intent-to-treat approach. The hazard ratio of time-to-first event will be estimated from a Cox model. Within-center correlation will be considered using a robust sandwich estimator. Observation time will be censored on the trial end date or when patients die from a noncardiovascular event. TRIAL REGISTRATION www.clinicaltrials.gov; identifier: NCT02628366.
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Affiliation(s)
- Ahmed A. Al-Jaishi
- London Health Sciences Centre, ON, Canada
- ICES, ON, Canada
- McMaster University, Hamilton, ON, Canada
| | | | - Jessica M. Sontrop
- London Health Sciences Centre, ON, Canada
- Western University, London, ON, Canada
| | - Stephanie N. Dixon
- London Health Sciences Centre, ON, Canada
- ICES, ON, Canada
- Western University, London, ON, Canada
| | | | | | | | - David Berry
- Sault Area Hospital, Sault Ste. Marie, ON, Canada
| | - Peter G. Blake
- London Health Sciences Centre, ON, Canada
- Western University, London, ON, Canada
| | | | | | | | | | | | | | | | - Jeremy M. Grimshaw
- Ottawa Hospital Research Institute, ON, Canada
- University of Ottawa, ON, Canada
| | | | | | - Arsh K. Jain
- London Health Sciences Centre, ON, Canada
- ICES, ON, Canada
- Western University, London, ON, Canada
| | | | - Reem A. Mustafa
- McMaster University, Hamilton, ON, Canada
- University of Kansas Medical Center, Kansas City, USA
| | | | | | - Matthew J. Oliver
- Sunnybrook Health Sciences Centre, Toronto, ON, Canada
- University of Toronto, ON, Canada
| | | | | | | | - Justin Presseau
- Ottawa Hospital Research Institute, ON, Canada
- University of Ottawa, ON, Canada
| | - Eli Rabin
- Niagara Health System, St. Catharines, ON, Canada
| | | | | | - Manish M. Sood
- ICES, ON, Canada
- Ottawa Hospital Research Institute, ON, Canada
- University of Ottawa, ON, Canada
| | | | - Paul Tam
- Scarborough Health Network, ON, Canada
| | | | | | - Ron Wald
- ICES, ON, Canada
- University of Toronto, ON, Canada
- St. Michael’s Hospital, Toronto, ON, Canada
| | - Michael Walsh
- McMaster University, Hamilton, ON, Canada
- St. Joseph’s Healthcare, Hamilton, ON, Canada
| | - Paul Watson
- Thunder Bay Regional Health Sciences Centre, ON, Canada
| | | | | | | | - Amit X. Garg
- London Health Sciences Centre, ON, Canada
- ICES, ON, Canada
- McMaster University, Hamilton, ON, Canada
- Western University, London, ON, Canada
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Nathoo B, Stroz M, Stroz P. A Central Venous Catheter That Cannot Be Dislodged Easily by a Confused Patient. Ann Intern Med 2019; 171:386. [PMID: 31476220 DOI: 10.7326/l19-0343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Bharat Nathoo
- Mackenzie Health, Richmond Hill, Ontario, Canada (B.N.)
| | | | - Peter Stroz
- Mackenzie Health, Toronto, Ontario, Canada (M.S., P.S.)
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LAU Y, Denis J, Gray B, Nathoo B. MON-078 IMPACT OF RAPID PERITONEAL DIALYSIS (PD) GROWTH ON PERITONITIS RATE IN A REGIONAL RENAL PROGRAM IN ONTARIO. Kidney Int Rep 2019. [DOI: 10.1016/j.ekir.2019.05.867] [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: 10/26/2022] Open
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Jialal I, Camacho F, Nathoo B, Tam P, Pahwa R, Wu GG. Fibroblast Growth Factor 23 Predicts Mortality and End-Stage Renal Disease in a Canadian Asian Population with Chronic Kidney Disease. Nephron Clin Pract 2017; 137:190-196. [PMID: 28743129 DOI: 10.1159/000479300] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [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: 02/28/2017] [Accepted: 06/29/2017] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Chronic kidney disease (CKD) is a leading cause of morbidity and mortality. Biomarkers that predict end-stage renal disease (ESRD) and/or mortality could usher in new therapeutics to halt this onslaught. While fibroblast growth factor (FGF)23 can predict both ESRD and mortality, it has not been studied in North American CKD patients of Asian ethnicity. METHOD This is a prospective investigation about the role of FGF23 in 998 Canadian patients of Asian descent with CKD defined by an estimated glomerular filtration rate (eGFR) <60 mL/min/m2 and followed up for 3 years. RESULTS The mean age of patients was 68.9 years and 68.3% were males. The mean (range) eGFR, and median FGF23 were 40.2 (11.0-59.0) mL/min and 154.1 (7.0-7,823.0) RU/mL, respectively. Over the 3 years, higher values of FGF23 levels at baseline were associated with higher risk of ESRD (hazard ratio [HR] for log[Fgf23] = 2.16 [95% CI 1.20-3.89]). Despite the short follow-up, 42 patients died due to cardiovascular diseases (38.8%), cancer (14.9%), and infections (12.7%). Log-FGF23 levels were independently associated with death, HR 1.94, 95% CI 1.24-3.03. Mortality risk increased in FGF23 subgroups from <100 to >400 RU/mL. In a time-changing covariate analysis, serial log-FGF23 levels over the 3 years predicted mortality with a HR of 2.66 (95% CI 1. 79-3.95). CONCLUSION In a Canadian Asian population with CKD, FGF23 levels obtained at 6-monthly intervals for 3 years predicted ESRD and mortality suggesting that it is also a risk marker in Asians.
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Affiliation(s)
- Ishwarlal Jialal
- California North-State University College of Medicine and the Sacramento VA Medical Center, Sacramento, CA, USA
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Kosa SD, Gafni A, House AA, Lawrence J, Moist L, Nathoo B, Tam P, Sarabia A, Thabane L, Wu G, Lok CE. Hemodialysis Infection Prevention Protocols Ontario-Shower Technique (HIPPO-ST): A Pilot Randomized Trial. Kidney Int Rep 2017; 2:228-238. [PMID: 29142959 PMCID: PMC5678668 DOI: 10.1016/j.ekir.2016.11.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 10/28/2016] [Accepted: 11/01/2016] [Indexed: 11/01/2022] Open
Abstract
INTRODUCTION We developed the Hemodialysis Infection Prevention Protocols Ontario-Shower Technique (HIPPO-ST) to permit hemodialysis (HD) patients with central venous catheters (catheters) to shower without additional infection risk. Our primary objective was to determine the feasibility of conducting a parallel randomized controlled trial (RCT) to evaluate the impact of HIPPO-ST on catheter-related bacteremia (CRB) in adult HD patients. METHODS Adult HD patients using catheters were recruited from 11 HD units. Patients were randomized to receive HIPPO-ST or standard care and were followed up for 6 months. Only CRB-outcome assessors were blinded. For the study to be considered feasible, 4 of 5 feasibility outcomes, each with its own statistical threshold for success, must have been achieved. RESULTS A total of 68 patients were randomized (33 HIPPO-ST and 35 control) and were followed up to 6 months. Of 5 measures of feasibility, 4 were achieved: (1) accurate CRB rate documented (threshold: κ level >0.80); (2) 97.8% (279/285) of satellite HD patients with catheters were screened (threshold: >95%); (3) 88% (23/26) in the HIPPO-ST arm were successfully educated by 6 months (threshold: >80%); and (4) 0% (0/29) patients in the control arm were "contaminated," that is, using HIPPO-ST (threshold: <5%). However, only 44.2% (72/163) of eligible patients consented to participate (threshold: >80%). The rate of CRB was similarly low in HIPPO-ST and control groups (0.68 vs. 0.88/1000 catheter days). DISCUSSION This HIPPO-ST pilot study demonstrated the feasibility of the larger HIPPO-ST study, especially given the high levels of education success with the HIPPO-ST arm and the low levels of contamination in the control arm.
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Affiliation(s)
- S. Daisy Kosa
- University Health Network-Toronto General Hospital, Toronto, Ontario, Canada
- McMaster University, Hamilton, Ontario, Canada
| | - Amiram Gafni
- University Health Network-Toronto General Hospital, Toronto, Ontario, Canada
| | | | | | - Louise Moist
- London Health Sciences Centre, London, Ontario, Canada
| | | | - Paul Tam
- The Scarborough Hospital, Scarborough, Ontario, Canada
| | | | | | - George Wu
- Credit Valley Hospital, Mississauga, Ontario, Canada
| | - Charmaine E. Lok
- University Health Network-Toronto General Hospital, Toronto, Ontario, Canada
- McMaster University, Hamilton, Ontario, Canada
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Levin A, Rigatto C, Barrett B, Madore F, Muirhead N, Holmes D, Clase CM, Tang M, Djurdjev O, Agharazii M, de Québec; LD, Akbarii A, Barré P, Barrett B, Clase C, Cooper S, Forzley B, Cournoyer S, Dionne J, Donnelly S, Hemmelgarn B, Keown P, Zalunardo, N, Levin A, Lok C, Madore F, Moist L, Muirhead N, Nathoo B, Parmar M, Leblanc M, Rigatto C, Soroka S, Thanamayooran S, Tobe S, Yeates K. Biomarkers of inflammation, fibrosis, cardiac stretch and injury predict death but not renal replacement therapy at 1 year in a Canadian chronic kidney disease cohort. Nephrol Dial Transplant 2013; 29:1037-47. [DOI: 10.1093/ndt/gft479] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- Adeera Levin
- University of British Columbia, Vancouver, Canada
| | | | | | | | | | | | | | - Mila Tang
- St. Paul's Hospital, Vancouver, Canada
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Wu G, Wadgymar A, Wong G, Ting R, Nathoo B, Mendelssohn D, Pandeya S, Sapir D, Tam P. A cross-sectional immunosurveillance study of anti-EPO antibody levels in CRF patients receiving epoetin alfa in 5 Ontario Renal Centers. Am J Kidney Dis 2005; 44:264-9. [PMID: 15264184 DOI: 10.1053/j.ajkd.2004.04.031] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [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: 11/11/2022]
Abstract
BACKGROUND Epoetin alfa (Eprex*; Johnson & Johnson, Manati, PR) has been used successfully to correct the anemia of chronic renal failure for more than 12 years. Anti-erythropoietin (anti-EPO) antibodies have been reported in a small number of patients, resulting in a blood disorder, pure red cell aplasia (PRCA). To evaluate the utility of a large-scale anti-EPO antibody screening program in patients with chronic kidney disease (CKD) administered epoetin alfa, a study involving 5 large renal centers in southern Ontario, Canada, was conducted. METHODS More than 1,500 hemodialysis, peritoneal dialysis, and predialysis patients were screened for the prevalence of anti-EPO antibodies by means of a radioimmunoprecipitation (RIP) assay. Serum samples were drawn and shipped to PPD Development (Richmond, VA) for the immunoprecipitation assay. Serum EPO levels also were measured. All samples that tested positive or borderline for antibodies were sent to MDS Pharma Services (Montreal, Canada) for the neutralization assay. RESULTS Of 1,531 samples tested, 1 patient tested low-positive and 3 borderline results were detected by means of RIP. PRCA previously was diagnosed in the patient with the low-positive antibody level; the patient was treated with cyclosporine and currently is being administered epoetin alfa with good response. The 3 patients with borderline antibody results manifested no clinical signs of PRCA. Neutralization assays performed on all 4 serum samples were negative for anti-EPO antibodies. CONCLUSION Results from this surveillance study show that the prevalence of antibody to EPO in patients with CKD administered epoetin alfa in 5 Canadian renal centers is low, and the value of a large-scale antibody screening program for PRCA cannot be justified.
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Affiliation(s)
- George Wu
- Institute of Kidney Lifescience Technologies, Toronto, Ontario, Canada.
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