Eculizumab as a New Treatment for Severe Acute Post-infectious Glomerulonephritis: Two Case Reports

Acute post-infections glomerulonephritis (APIGN) is a frequent cause of glomerulonephritis and represents the most common cause of acute glomerulonephritis in children. It can evolve to severe acute renal failure and chronic kidney disease or even end-stage kidney disease. The precise pathophysiological mechanisms of APIGN are still incompletely understood. The implication of the alternative complement pathway and the potential benefits of C5 blockade have been recently highlighted, in particular in the presence of a C3 Nephritic Factor (C3Nef), anti-Factor B or H autoantibodies. We report two children with severe APIGN, successfully treated with eculizumab. The first patient presented a severe form of APIGN with advanced renal failure and anuria, associated with a decreased level of C3 and an increased level of soluble C5b-9, in the presence of a C3NeF autoantibody. The second case had a severe oliguric APIGN associated with low C3 level. Kidney biopsy confirmed the diagnosis of APIGN in both cases. Eculizumab allowed full renal function recovery and the avoidance of dialysis in both cases. In conclusion, the alternative and terminal complement pathways activation might be common in PIGN, and in severe cases, eculizumab might help.

The Gut and Blood Microbiome in IgA Nephropathy and Healthy Controls

Background

IgA nephropathy (IgAN) has been associated with gut dysbiosis, intestinal membrane disruption, and translocation of bacteria into blood. Our study aimed to understand the association of gut and blood microbiomes in patients with IgAN in relation to healthy controls.

Methods

We conducted a case-control study with 20 patients with progressive IgAN, matched with 20 healthy controls, and analyzed bacterial DNA quantitatively in blood using 16S PCR and qualitatively in blood and stool using 16S metagenomic sequencing. We conducted between-group comparisons as well as comparisons between the blood and gut microbiomes.

Results

Higher median 16S bacterial DNA in blood was found in the IgAN group compared with the healthy controls group (7410 versus 6030 16S rDNA copies/μl blood, P=0.04). α- and β-Diversity in both blood and stool was largely similar between the IgAN and healthy groups. In patients with IgAN, in comparison with healthy controls, we observed higher proportions of the class Coriobacteriia and species of the genera Legionella, Enhydrobacter, and Parabacteroides in blood, and species of the genera Bacteroides, Escherichia-Shigella, and some Ruminococcus in stool. Taxa distribution were markedly different between the blood and stool samples of each subject in both IgAN and healthy groups, without any significant correlation between corresponding gut and blood phyla.

Conclusions

Important bacterial taxonomic differences, quantitatively in blood and qualitatively in both blood and stool samples, that were detected between IgAN and healthy groups warrant further investigation into their roles in the pathogenesis of IgAN. Although gut bacterial translocation into blood may be one of the potential sources of the blood microbiome, marked taxonomic differences between gut and blood samples in each subject in both groups confirms that the blood microbiome does not directly reflect the gut microbiome. Further research is needed into other possible sites of origin and internal regulation of the blood microbiome.

Filter clotting with continuous renal replacement therapy in COVID-19

Coronavirus disease 2019 (COVID-19) appears to be associated with increased arterial and venous thromboembolic disease. These presumed abnormalities in hemostasis have been associated with filter clotting during continuous renal replacement therapy (CRRT). We aimed to characterize the burden of CRRT filter clotting in COVID-19 infection and to describe a CRRT anticoagulation protocol that used anti-factor Xa levels for systemic heparin dosing. Multi-center study of consecutive patients with COVID-19 receiving CRRT. Primary outcome was CRRT filter loss. Sixty-five patients were analyzed, including 17 using an anti-factor Xa protocol to guide systemic heparin dosing. Fifty-four out of 65 patients (83%) lost at least one filter. Median first filter survival time was 6.5 [2.5, 33.5] h. There was no difference in first or second filter loss between the anti-Xa protocol and standard of care anticoagulation groups, however fewer patients lost their third filter in the protocolized group (55% vs. 93%) resulting in a longer median third filter survival time (24 [15.1, 54.2] vs. 17.3 [9.5, 35.1] h, p = 0.04). The rate of CRRT filter loss is high in COVID-19 infection. An anticoagulation protocol using systemic unfractionated heparin, dosed by anti-factor Xa levels is reasonable approach to anticoagulation in this population.

Resolution of a High Grade and Metastatic BK Polyomavirus-Associated Urothelial Cell Carcinoma Following Radical Allograft Nephroureterectomy and Immune Checkpoint Treatment: A Case Report

BACKGROUND

BK viral infection in the posttransplant setting continues to cause serious morbidity with effects ranging from allograft nephropathy and dysfunction to urothelial malignancy.

RESULTS

In this report, we present a patient that developed BK-associated nephropathy and, 6 years later, locally advanced urothelial malignancy in the renal allograft with nodal, muscle, and extremity involvement. Following radical allograft nephroureterectomy, he was treated with palliative radiation and the immune checkpoint inhibitor atezolizumab. Follow-up imaging at 1 year demonstrated radiographic complete response.

CONCLUSIONS

This report supports the growing body of evidence supporting the association of urothelial malignancy and BK virus infection in renal transplant recipients. Further, it highlights the novel application of immune checkpoint inhibitors in the treatment of advanced posttransplant malignancy, in particular when the allograft is removed and the tumor is possibly of donor origin.

Accelerated Venovenous Hemofiltration as a Transitional Renal Replacement Therapy in the Intensive Care Unit

BACKGROUND

Continuous renal replacement therapy (CRRT) is commonly employed in the intensive care unit (ICU), though there are no guidelines around the transition between CRRT and intermittent hemodialysis (iHD). Accelerated venovenous hemofiltration (AVVH) is a modality utilizing higher hemofiltration rates (4-5 L/h) with shorter session durations (8-10 h) to "accelerate" the clearance and volume removal that normally is spread out over a 24-h period in CRRT. We examined AVVH as a transition therapy between CRRT and iHD, with the aim of decreasing time on CRRT and providing a more graduated transition for hemodynamically unstable patients requiring RRT.

METHODS

Retrospective cohort study describing the clinical outcomes and quality initiative experience of the integration of AVVH into the CRRT program at an academic tertiary care center. Outcomes of interest included mortality, ICU length of stay and readmission rates, and technical characteristics of treatments.

RESULTS

In total, 97 patients received a total of 298 AVVH treatments (3.1 ± 3.3 treatments per patient). Totally, 271/298 (91%) treatments were completed successfully. During an average treatment time of 9.5 ± 1.6 h with 4.2 ± 0.5 L/h -replacement fluid rate, urea reduction ratio was 23 ± 26% per 10-h treatment, and net ultrafiltration volume was 2.4 ± 1.3 L/treatment. Inpatient mortality was 32%, mean total hospital length of stay was 54 ± 47 days. Sixty-four out of 97 (66%) patients recovered renal function by discharge. Among those who transferred out of the ICU, 7/62 (11%) patients required readmission to the ICU after developing hypotension on iHD.

CONCLUSION

AVVH can serve as a transition therapy between CRRT and iHD in the ICU and has the potential to decrease total time on CRRT, improve patient mobility, and sustain low ICU readmission rates. Future study is needed to analyze the implications on resource use and cost of this modality.

Hemodialysis failure secondary to hydroxocobalamin exposure

Hydroxocobalamin is a recently approved antidote for the treatment of cyanide poisoning. The case presented involves a young patient administered empiric hydroxocobalamin due to suspected cyanide overdose. Due to the development of acute kidney injury and severe metabolic derangement, emergent hemodialysis was initiated. Unfortunately, hemodialysis was confounded by a recurrent "blood leak" alarm. This unforeseen effect was secondary to interference from hydroxocobalamin. Hydroxocobalamin causes orange/red discoloration of bodily fluids and permeates the dialysate. This leads to defraction of light in the effluent path of the blood leak detector from discolored dialysate, which can result in activation of the blood leak alarm and an inability to continue hemodialysis treatment. This case highlights several new and emerging critical concerns with this medication, including the potential consequence of delayed initiation of emergent renal replacement therapy with empiric administration, the need for increased awareness among clinicians of various disciplines, and the need for multidisciplinary communication.

Lanthanum deposition from oral lanthanum carbonate in the upper gastrointestinal tract

AIMS

Lanthanum carbonate is used as an alternative to calcium-based phosphate binders to manage hyperphosphataemia in patients with renal failure. The deposition of lanthanum within gastroduodenal mucosa of patients treated with the medication has been described, but given the relative novelty of this entity, the histiocytic deposits in the gastroduodenal mucosa can be confused with a variety of other processes, including infections and other drug-induced forms of injury.

METHODS AND RESULTS

We describe five cases of lanthanum phosphate deposition in upper gastrointestinal (GI) tract biopsies. Three cases were confirmed with scanning electron microscopy and energy dispersive X-ray analysis, including one unique patient, status post-renal transplant for polycystic kidney disease, who had last taken lanthanum 7 years prior to biopsy.

CONCLUSION

Lanthanum deposition in the upper GI tract is a mimic of other drug-related forms of GI injury, including iron pill-related gastropathy. The key to making this diagnosis is a thorough drug history and awareness of the histological features.

Voriconazole-Induced Periostitis & Enthesopathy in Solid Organ Transplant Patients: Case Reports

Background

Voriconazole is frequently used to treat fungal infections in solid organ transplant patients. Recently, there have been reports suggesting that prolonged voriconazole therapy may lead to periostitis.

Aim

Here we present two cases of voriconazole-induced periostitis in solid organ transplant patients.

Case Presentation

Voriconazole was given to two transplant patients-one with a liver transplant and the second with a heart transplant, to treat their fungal infections. Both developed voriconazole-induced toxicity. While undergoing voriconazole therapy, they had incapacitating bone pain. The liver transplant patient had to be taken off voriconazole, and the heart transplant patient succumbed to non-voriconazole related causes.

Conclusions

Voriconazole therapy in two solid organ transplant patients resulted in periostitis. We provide potential etiologies underlying voriconazole-induced periostitis, including fluoride toxicity, abnormalities in the pulmonary vascular bed leading to the production of downstream inflammatory mediators, and abnormal pharmacokinetics of hepatic drug metabolism. In addition to monitoring blood voriconazole trough levels, we suggest careful assessment for musculoskeletal pain in patients undergoing voriconazole treatment for two months or more, particularly if their daily dosages of voriconazole exceed 500 mg per day. Appropriate workup should include measurement of alkaline phosphatase, voriconazole trough and fluoride levels as well as a bone scan. Overall, early recognition of voriconazole-induced musculoskeletal toxicity is important for better morbidity outcomes.

Reproduction and Pregnancy in Transplant Recipients: Current Practices

Many transplant physicians are faced with questions from their patients about the safety and long-term consequences of pregnancy following transplantation. To better understand how pregnancies are managed and to clarify the outcome of pregnancy after transplantation, a survey questionnaire was developed and mailed to all medical and surgical directors of transplant centers throughout the United States; responses were obtained from 59.1% of the transplant centers. Although many opinions were collected, most respondents conceded that their opinions were based on personal experience rather than evidence-based. The underutilization of existing information was revealing and highlighted a need for an evidence-based approach to care of the pregnant transplant recipient and her offspring. The survey results, reported in this article, led to formation of a consensus conference to determine the optimal approach to pregnant transplant recipients and to define what is currently known and unknown about reproduction and transplantation.

Longitudinal studies of a B cell-derived signature of tolerance in renal transplant recipients

Biomarkers of transplant tolerance would enhance the safety and feasibility of clinical tolerance trials and potentially facilitate management of patients receiving immunosuppression. To this end, we examined blood from spontaneously tolerant renal transplant recipients and patients enrolled in two interventional tolerance trials using flow cytometry and gene expression profiling. Using a previously reported tolerant cohort as well as newly identified tolerant patients, we confirmed our previous finding that tolerance was associated with increased expression of B cell-associated genes relative to immunosuppressed patients. This was not accounted for merely by an increase in total B cell numbers, but was associated with the increased frequencies of transitional and naïve B cells. Moreover, serial measurements of gene expression demonstrated that this pattern persisted over several years, although patients receiving immunosuppression also displayed an increase in the two most dominant tolerance-related B cell genes, IGKV1D-13 and IGLL-1, over time. Importantly, patients rendered tolerant via induction of transient mixed chimerism, and those weaned to minimal immunosuppression, showed similar increases in IGKV1D-13 as did spontaneously tolerant individuals. Collectively, these findings support the notion that alterations in B cells may be a common theme for tolerant kidney transplant recipients, and that it is a useful monitoring tool in prospective trials.

Immune Complex Tubulointerstitial Nephritis Due to Autoantibodies to the Proximal Tubule Brush Border

Immune complex tubulointerstitial nephritis due to antibodies to brush border antigens of the proximal tubule has been demonstrated experimentally and rarely in humans. Our patient developed ESRD and early recurrence after transplantation. IgG and C3 deposits were conspicuous in the tubular basement membrane of proximal tubules, corresponding to deposits observed by electron microscopy. Rare subepithelial deposits were found in the glomeruli. The patient had no evidence of SLE and had normal complement levels. Serum samples from the patient reacted with the brush border of normal human kidney, in contrast with the negative results with 20 control serum samples. Preliminary characterization of the brush border target antigen excluded megalin, CD10, and maltase. We postulate that antibodies to brush border antigens cause direct epithelial injury, accumulate in the tubular basement membrane, and elicit an interstitial inflammatory response.

BK Virus After Kidney Transplantation: A Review of Screening and Treatment Strategies and a Summary of the Massachusetts General Hospital Experience

BK virus (BKV) is a common infection encountered after kidney transplantation. BKV is associated with a spectrum of manifestations, starting with sub-clinical viruria, followed by viremia and BKV-associated nephropathy. Standard of care includes routine post-transplant screening for BK viruria and/or viremia. Both the Kidney Disease Improving Global Outcomes and the American Society of Transplantation Infectious Diseases Community of Practice have published screening recommendations. Although they vary slightly, they both highlight the importance of early detection with serial screening. Once BK viremia is detected, the standard management approach includes a reduction of immunosuppression. Guidelines differ slightly about the sequence of the immunosuppression reduction, but the end result is the same: lowering the overall immunosuppressive burden in the patient with BKV infection. At the Massachusetts General Hospital, from 2007 to 2009, there was no BKV screening protocol in place. The rate of screening during this time period increased from 62% to 81%. A total of 29 of the 243 patients were diagnosed with BK viremia (11.9%), with 23 identified as a result of screening and 6 as a result of testing for graft dysfunction. We developed a BKV screening protocol consisting of BKV polymerase chain reaction testing in blood starting 2 months after kidney transplantation and every 2 months thereafter, continuing through month 24 regardless of the allograft function. Additional screening for 6 more months is performed in patients who receive anti-lymphocyte globulin for the treatment of acute rejection. Finally, all patients with otherwise unexplained allograft dysfunction are screened. Currently, work is being done investigating the use of mammalian target of rapamycin inhibitors to treat BKV infection. Trials are also ongoing evaluating cell-based therapies for BKV. Research to develop a vaccine or a direct-acting antiviral agent is in critical need and an area of research that should be given high priority.

Safety and efficacy of ceftriaxone for amyotrophic lateral sclerosis: a multi-stage, randomised, double-blind, placebo-controlled trial

BACKGROUND

Glutamate excitotoxicity might contribute to the pathophysiology of amyotrophic lateral sclerosis. In animal models, decreased excitatory aminoacid transporter 2 (EAAT2) overexpression delays disease onset and prolongs survival, and ceftriaxone increases EAAT2 activity. We aimed to assess the safety and efficacy of ceftriaxone for amyotrophic lateral sclerosis in a combined phase 1, 2, and 3 clinical trial.

METHODS

This three-stage randomised, double-blind, placebo-controlled study was done at 59 clinical sites in the USA and Canada between Sept 4, 2006, and July 30, 2012. Eligible adult patients had amyotrophic lateral sclerosis, a vital capacity of more than 60% of that predicted for age and height, and symptom duration of less than 3 years. In stages 1 (pharmacokinetics) and 2 (safety), participants were randomly allocated (2:1) to ceftriaxone (2 g or 4 g per day) or placebo. In stage 3 (efficacy), participants assigned to ceftriaxone in stage 2 received 4 g ceftriaxone, participants assigned to placebo in stage 2 received placebo, and new participants were randomly assigned (2:1) to 4 g ceftriaxone or placebo. Participants, family members, and site staff were masked to treatment assignment. Randomisation was done by a computerised randomisation sequence with permuted blocks of 3. Participants received 2 g ceftriaxone or placebo twice daily through a central venous catheter administered at home by a trained caregiver. To minimise biliary side-effects, participants assigned to ceftriaxone also received 300 mg ursodeoxycholic acid twice daily and those assigned to placebo received matched placebo capsules. The coprimary efficacy outcomes were survival and functional decline, measured as the slope of Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) scores. Analyses were by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00349622.

FINDINGS

Stage 3 included 66 participants from stages 1 and 2 and 448 new participants. In total, 340 participants were randomly allocated to ceftriaxone and 173 to placebo. During stages 1 and 2, mean ALSFRS-R declined more slowly in participants who received 4 g ceftriaxone than in those on placebo (difference 0·51 units per month, 95% CI 0·02 to 1·00; p=0·0416), but in stage 3 functional decline between the treatment groups did not differ (0·09, -0·06 to 0·24; p=0·2370). No significant differences in survival between the groups were recorded in stage 3 (HR 0·90, 95% CI 0·71 to 1·15; p=0·4146). Gastrointestinal adverse events and hepatobiliary adverse events were more common in the ceftriaxone group than in the placebo group (gastrointestinal, 245 of 340 [72%] ceftriaxone vs 97 of 173 [56%] placebo, p=0·0004; hepatobiliary, 211 [62%] vs 19 [11%], p<0·0001). Significantly more participants who received ceftriaxone had serious hepatobiliary serious adverse events (41 participants [12%]) than did those who received placebo (0 participants).

INTERPRETATION

Despite promising stage 2 data, stage 3 of this trial of ceftriaxone in amyotrophic lateral sclerosis did not show clinical efficacy. The adaptive design allowed for seamless transition from one phase to another, and central venous catheter use in the home setting was shown to be feasible.

FUNDING

National Institute of Neurological Disorders and Stroke.

Long-term results in recipients of combined HLA-mismatched kidney and bone marrow transplantation without maintenance immunosuppression

We report here the long-term results of HLA-mismatched kidney transplantation without maintenance immunosuppression (IS) in 10 subjects following combined kidney and bone marrow transplantation. All subjects were treated with nonmyeloablative conditioning and an 8- to 14-month course of calcineurin inhibitor with or without rituximab. All 10 subjects developed transient chimerism, and in seven of these, IS was successfully discontinued for 4 or more years. Currently, four subjects remain IS free for periods of 4.5-11.4 years, while three required reinstitution of IS after 5-8 years due to recurrence of original disease or chronic antibody-mediated rejection. Of the 10 renal allografts, three failed due to thrombotic microangiopathy or rejection. When compared with 21 immunologically similar living donor kidney recipients treated with conventional IS, the long-term IS-free survivors developed significantly fewer posttransplant complications. Although most recipients treated with none or two doses of rituximab developed donor-specific antibody (DSA), no DSA was detected in recipients treated with four doses of rituximab. Although further revisions of the current conditioning regimen are planned in order to improve consistency of the results, this study shows that long-term stable kidney allograft survival without maintenance IS can be achieved following transient mixed chimerism induction.

Native portal vein embolization for persistent hyperoxaluria following kidney and auxiliary partial liver transplantation

Type 1 primary hyperoxaluria (PH1) causes renal failure, for which isolated kidney transplantation (KT) is usually unsuccessful treatment due to early oxalate stone recurrence. Although hepatectomy and liver transplantation (LT) corrects PH1 enzymatic defect, simultaneous auxiliary partial liver transplantation (APLT) and KT have been suggested as an alternative approach. APLT advantages include preservation of the donor pool and retention of native liver function in the event of liver graft loss. However, APLT relative mass may be inadequate to correct the defect. We here report the first case of native portal vein embolization (PVE) to increase APLT to native liver mass ratio (APLT/NLM-R). Following initial combined APLT-KT, both allografts functioned well, but oxalate plasma levels did not normalize. We postulated the inadequate APLT/NLM-R could be corrected by trans-hepatic native PVE. The resulting increased APLT/NLM-R decreased serum oxalate to normal levels within 1 month following PVE. We conclude that persistently elevated oxalate levels after combined APLT-KT for PH1 treatment, results from inadequate relative functional capacity. This can be reversed by partial native PVE to decrease portal flow to the native liver. This approach might be applicable to other scenarios where partial grafts have been transplanted to replace native liver function.

Partial therapeutic response to Rituximab for the treatment of chronic alloantibody mediated rejection of kidney allografts

BACKGROUND AND OBJECTIVES

Chronic rejection leads to kidney allograft failure and develops in many kidney transplant recipients. One cause of chronic rejection, chronic antibody mediated rejection (CAMR), is attributed to alloantibodies. Maintenance immunosuppression including prednisone, mycophenolate mofetil (MMF) and calcineurin inhibitors may limit alloantibody production in some patients, but many maintain or develop alloantibody production, leading to CAMR. Therefore, no efficacious therapy to treat CAMR is presently available to prevent the progression of CAMR to kidney allograft failure.

DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS

We performed a retrospective review of 31 subjects with CAMR, of which 14 received Rituximab and 17 subjects did not. Response to Rituximab was defined as decline or stabilization of serum creatinine for at least one year. Data reviewed included demographic, clinical, allograft, post-transplant, and pathological variables. Pathological variables in the diagnostic allograft biopsy were scored according to Banff criteria.

RESULTS

The median survival time (MST) for allografts in the control group was 439 days, and for the Rituximab treated group was 685 days. The Rituximab group was dichotomous with 8 subjects showing a medial survival time of 1180 days, and 6 subjects having a median survival time of 431 days. The MST for the responders was statistically significant from the non-responders and controls. No pathological parameter distinguished any subset of subjects.

CONCLUSIONS

These data show that Rituximab followed by standard maintenance immunosuppression shows a therapeutic effect in the treatment of CAMR, which is confined to a subset of treated subjects, not identifiable a priori.

Clinical role of the renal transplant biopsy

Percutaneous needle core biopsy is the definitive procedure by which essential diagnostic and prognostic information on acute and chronic renal allograft dysfunction is obtained. The diagnostic value of the information so obtained has endured for over three decades and has proven crucially important in shaping strategies for therapeutic intervention. This Review provides a broad outline of the utility of performing kidney graft biopsies after transplantation, highlighting the relevance of biopsy findings in the immediate and early post-transplant period (from days to weeks after implantation), the first post-transplant year, and the late period (beyond the first year). We focus on how biopsy findings change over time, and the wide variety of pathological features that characterize the major clinical diagnoses facing the clinician. This article also includes a discussion of acute cellular and humoral rejection, the toxic effects of calcineurin inhibitors, and the widely varying etiologies and characteristics of chronic lesions. Emerging technologies based on gene expression analyses and proteomics, the in situ detection of functionally relevant molecules, and new bioinformatic approaches that hold the promise of improving diagnostic precision and developing new, refined molecular pathways for therapeutic intervention are also presented.

Early outcomes among those initiating chronic dialysis in the United States

BACKGROUND AND OBJECTIVES

Approximately one million Americans initiated chronic dialysis over the past decade; the first-year mortality rate reported by the U.S. Renal Data System was 19.6% in 2007. This estimate has historically excluded the first 90 days of chronic dialysis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

To characterize the mortality and hospitalization risks for patients starting chronic renal replacement therapy, we followed all patients initiating dialysis in 1733 facilities throughout the United States (n = 303,289). Mortality and hospitalizations within the first 90 days were compared with outcomes after this period, and the results were analyzed. Standard time-series analyses were used to depict the weekly risk estimates for each outcome.

RESULTS

Between 1997 and 2009, >300,000 patients initiated chronic dialysis and were followed for >35 million dialysis treatments; the highest risk for morbidity and mortality occurred in the first 2 weeks of treatment. The initial 2-week risk of death for a typical dialysis patient was 2.72-fold higher, and the risk of hospitalization was 1.95-fold higher when compared to a patient who survived the first year of chronic dialysis (week 53 after initiation). Similarly, over the first 90 days, the risk of mortality and hospitalization remained elevated. Thereafter, between days 91 and 365, these risks decreased considerably by more than half. Surviving these first weeks of dialysis was most associated with the type of vascular access. Initiating dialysis with a fistula was associated with a decreased early death risk by 61%, whereas peritoneal dialysis decreased the risk by 87%.

CONCLUSIONS

The first 2 weeks of chronic dialysis are associated with heightened mortality and hospitalization risks, which remain elevated over the ensuing 90 days.

Adults with Sotos syndrome: review of 21 adults with molecularly confirmed NSD1 alterations, including a detailed case report of the oldest person

Sotos syndrome is a well-described multiple anomaly syndrome characterized by overgrowth, distinctive craniofacial appearance, and variable learning disabilities. The diagnosis of Sotos syndrome relied solely on these clinical criteria until haploinsufficiency of the NSD1 gene was identified as causative. We describe a 63-year-old woman with classic features and a pathogenic NSD1 mutation, who we believe to be the oldest reported person with Sotos syndrome. She is notable for the diagnosis of Sotos syndrome late in life, mild cognitive limitation, and chronic kidney disease attributed to fibromuscular dysplasia for which she recently received a transplant. She has basal cell and squamous cell carcinoma for which her lifetime of sun exposure and fair cutaneous phototype are viewed as risk factors. We also reviewed previous literature reports (n = 11) for adults with Sotos syndrome, and studied patients ascertained in the Spanish Overgrowth Syndrome Registry (n = 15). Analysis was limited to 21/27 (78%) total patients who had molecular confirmation of Sotos syndrome (15 with a mutation, 6 with a microdeletion). With a mean age of 26 years, the most common features were learning disabilities (90%), scoliosis (52%), eye problems (43%), psychiatric issues (30%), and brain imaging anomalies (28%). Learning disabilities were more severe in patients with a microdeletion than in those with a point mutation. From this small study with heterogeneous ascertainment we suggest modest adjustments to the general healthcare monitoring of individuals with Sotos syndrome. Although this series includes neoplasia in four cases, this should not be interpreted as incidence. Age-appropriate cancer surveillance should be maintained.

Acute renal endothelial injury during marrow recovery in a cohort of combined kidney and bone marrow allografts

An idiopathic capillary leak syndrome ('engraftment syndrome') often occurs in recipients of hematopoietic cells, manifested clinically by transient azotemia and sometimes fever and fluid retention. Here, we report the renal pathology in 10 recipients of combined bone marrow and kidney allografts. Nine developed graft dysfunction on day 10-16 and renal biopsies showed marked acute tubular injury, with interstitial edema, hemorrhage and capillary congestion, with little or no interstitial infiltrate (≤10%) and marked glomerular and peritubular capillary (PTC) endothelial injury and loss by electron microscopy. Two had transient arterial endothelial inflammation; and 2 had C4d deposition. The cells in capillaries were primarily CD68(+) MPO(+) mononuclear cells and CD3(+) CD8(+) T cells, the latter with a high proliferative index (Ki67(+) ). B cells (CD20(+) ) and CD4(+) T cells were not detectable, and NK cells were rare. XY FISH showed that CD45(+) cells in PTCs were of recipient origin. Optimal treatment remains to be defined; two recovered without additional therapy, six were treated with anti-rejection regimens. Except for one patient, who later developed thrombotic microangiopathy and one with acute humoral rejection, all fully recovered within 2-4 weeks. Graft endothelium is the primary target of this process, attributable to as yet obscure mechanisms, arising during leukocyte recovery.

Chronic humoral rejection of human kidney allografts is associated with MMP-2 accumulation in podocytes and its release in the urine

Chronic humoral rejection (CHR) is an important cause of late graft failures following kidney transplantation. Overall, the pathophysiology of CHR is poorly understood. Matrix metalloproteinase-2 (MMP-2), a type IV collagenase, has been implicated in chronic kidney disease and allograft rejection in previous studies. We examined the presence of MMP-2 in allograft biopsies and in the urine of kidney transplant recipients with CHR. MMP-2 staining was detected by immunohistochemistry in podocytes for all CHR patients but less frequently in patients with other renal complications. Urinary MMP-2 levels were also significantly higher in CHR patients (median 4942 pg/mL, N = 27) compared to non-CHR patients (median 598 pg/mL, N = 65; p < 0.001). Elevated urinary MMP-2 correlated with higher levels of proteinuria in both CHR and non-CHR patients. Longitudinal analysis indicated that increase in urine MMP-2 coincided with initial diagnosis of CHR as documented by the biopsies. Using an enzymatic assay, we demonstrated that MMP-2 was present in its active form in the urine of patients with CHR. Overall, our findings associate MMP-2 with glomerular injury as well as interstitial fibrosis and tubular atrophy observed in patients with CHR.

B-cell immunity in the context of T-cell tolerance after combined kidney and bone marrow transplantation in humans

Five patients with end-stage kidney disease received combined kidney and bone marrow transplants from HLA haploidentical donors following nonmyeloablative conditioning to induce renal allograft tolerance. Immunosuppressive therapy was successfully discontinued in four patients with subsequent follow-up of 3 to more than 6 years. This allograft acceptance was accompanied by specific T-cell unresponsiveness to donor antigens. However, two of these four patients showed evidence of de novo antibodies reactive to donor antigens between 1 and 2 years posttransplant. These humoral responses were characterized by the presence of donor HLA-specific antibodies in the serum with or without the deposition of the complement molecule C4d in the graft. Immunofluorescence staining, ELISA assays and antibody profiling using protein microarrays demonstrated the co-development of auto- and alloantibodies in these two patients. These responses were preceded by elevated serum BAFF levels and coincided with B-cell reconstitution as revealed by a high frequency of transitional B cells in the periphery. To date, these B cell responses have not been associated with evidence of humoral rejection and their clinical significance is still unclear. Overall, our findings showed the development of B-cell allo- and autoimmunity in patients with T-cell tolerance to the donor graft.

Hepatitis C virus infection in haemodialysis and kidney transplant patients

Chronic infection with hepatitis C virus (HCV) is an important global health problem. The prevalence of HCV is significantly higher in haemodialysis and kidney transplant patients, as compared to the general population. In spite of the relatively milder liver disease activity reported in HCV-infected haemodialysis patients, HCV infection adversely affects survival. Likewise, HCV has a detrimental effect on both patient and graft survival after kidney transplantation. However, patient survival is significantly better with kidney transplantation compared to remaining on dialysis; therefore, HCV infection alone should not be a contraindication to transplantation. Combination antiviral therapy with pegylated interferon-alpha and low-dose ribavirin is currently evolving in haemodialysis patients. Interferon-alpha (standard/pegylated) is relatively contraindicated after kidney transplantation because of an increased risk of allograft rejection. Therefore, antiviral treatment of transplant candidates while on dialysis remains the best option and may avoid the risk of HCV-associated liver and renal disease after transplantation. Large multi-centre clinical trials are required in HCV-infected haemodialysis and kidney transplant patients in order to define optimal therapeutic strategies before and after transplantation.

HLA-mismatched renal transplantation without maintenance immunosuppression

Five patients with end-stage renal disease received combined bone marrow and kidney transplants from HLA single-haplotype mismatched living related donors, with the use of a nonmyeloablative preparative regimen. Transient chimerism and reversible capillary leak syndrome developed in all recipients. Irreversible humoral rejection occurred in one patient. In the other four recipients, it was possible to discontinue all immunosuppressive therapy 9 to 14 months after the transplantation, and renal function has remained stable for 2.0 to 5.3 years since transplantation. The T cells from these four recipients, tested in vitro, showed donor-specific unresponsiveness and in specimens from allograft biopsies, obtained after withdrawal of immunosuppressive therapy, there were high levels of P3 (FOXP3) messenger RNA (mRNA) but not granzyme B mRNA.

Outcome of kidney transplantation using expanded criteria donors and donation after cardiac death kidneys: realities and costs

Expanded criteria donors (ECDs) and donation after cardiac death (DCD) provide more kidneys in the donor pool. However, the financial impact and the long-term benefits of these kidneys have been questioned. From 1998 to 2005, we performed 271 deceased donor kidney transplants into adult recipients. There were 163 (60.1%) SCDs, 44 (16.2%) ECDs, 53 (19.6%) DCDs and 11 (4.1%) ECD/DCDs. The mean follow-up was 50 months. ECD and DCD kidneys had a significantly higher incidence of delayed graft function, longer time to reach serum creatinine below 3 (mg/dL), longer length of stay and more readmissions compared to SCDs. The hospital charge was also higher for ECD, ECD/DCD and DCD kidneys compared to SCDs, primarily due to the longer length of stay and increased requirement for dialysis (70,030 dollars, 72,438 dollars, 72,789 dollars and 47,462 dollars, respectively, p < 0.001). Early graft survival rates were comparable among all groups. However, after a mean follow-up of 50 months, graft survival was significantly less in the ECD group compared to other groups. Although our observations support the utilization of ECD and DCD kidneys, these transplants are associated with increased costs and resource utilization. Revised reimbursement guidelines will be required for centers that utilize these organs.

Putative antibody-mediated rejection with C4d deposition in HLA-identical, ABO-compatible renal allografts

We sought evidence for non-MHC antibody-mediated rejection in renal allografts by a systematic study of rejected HLA-identical sibling renal allografts. Among 162 recipients of HLA-identical, ABO-compatible sibling donor kidneys transplanted at the Massachusetts General Hospital from 1964 to 2005, we identified 15 grafts that were lost from rejection and two additional grafts with reversible acute rejection, which provided 30 samples for study. All samples were stained for C4d by immunofluorescence in frozen tissue (n = 7) or by immunohistochemistry in paraffin embedded tissues (n = 10). We found that two of 17 grafts had positive C4d staining of peritubular capillaries. Histology revealed acute antibody-mediated rejection in one and acute cellular rejection type 1 in the other. Both grafts were matched at HLA-A, B, and C loci and had a nonreactive mixed lymphocyte response. Genotyping and serological analysis were not available. Compared with a published series, C4d+ irreversible rejection was more common in HLA nonidentical than HLA-identical grafts (75% vs 6.7%, respectively, P < .002). We conclude that antibody-mediated rejection, presumably due to non-MHC antigens other than ABO-blood groups does occur, but infrequently. This may account for some of the HLA antibody negative cases that develop antibody-mediated rejection.

Comparison of two dosages of thymoglobulin used as a short-course for induction in kidney transplantation

Thymoglobulin is used effectively as an induction agent in kidney transplantation, but the optimal dose is not well established. We evaluated the degree and durability of T-cell clearances with two different thymoglobulin regimens in adult kidney transplant recipients (KTR). Seven KTR received a 3-day thymoglobulin-based induction of 1.0 mg/kg/day while nine received 1.5 mg/kg/day, in addition to maintenance immunosuppression. Lymphocyte subsets were monitored for 6 months. Renal function, infections and malignancies were monitored for 24 months. T-cell subsets were significantly lower by day 30 with the thymoglobulin 1.5 mg/kg/day regimen when compared with the 1.0 mg/kg/day regimen; this trend was sustained at 6-month (CD3(+): 438 +/- 254 vs. 1001 +/- 532 cells/mm(3), P = 0.016). Renal function between the two groups was not significantly different at 6- and 24-months post-transplant. One case of BK Virus viremia in the 1.5 mg/kg/day thymoglobulin group was detected. No acute rejection episodes, cytomegalovirus infections, or malignancies were noted in either group. Thymoglobulin induction was efficacious in both groups, but with a significantly sustained T-cell clearance in the 1.5 mg/kg/day regimen. A more profound T-cell clearance within the first 6 months postinduction therapy may translate into a decreased risk of immunological injury and improved long-term outcome after kidney transplantation.

Myeloma responses and tolerance following combined kidney and nonmyeloablative marrow transplantation: in vivo and in vitro analyses

Six patients with renal failure due to multiple myeloma (MM) received simultaneous kidney and bone marrow transplantation (BMT) from HLA-identical sibling donors following nonmyeloablative conditioning, including cyclophosphamide (CP), peritransplant antithymocyte globulin and thymic irradiation. Cyclosporine (CyA) was given for approximately 2 months posttransplant, followed by donor leukocyte infusions. All six patients accepted their kidney grafts long-term. Three patients lost detectable chimerism but accepted their kidney grafts off immunosuppression for 1.3 to >7 years. One such patient had strong antidonor cytotoxic T lymphocyte (CTL) responses in association with marrow rejection. Two patients achieved full donor chimerism, but resumed immunosuppression to treat graft-versus-host disease. Only one patient experienced rejection following CyA withdrawal. He responded to immunosuppression, which was later successfully withdrawn. The rejection episode was associated with antidonor Th reactivity. Patients showed CTL unresponsiveness to cultured donor renal tubular epithelial cells. Initially recovering T cells were memory cells and were enriched for CD4+CD25+ cells. Three patients are in sustained complete remissions of MM, despite loss of chimerism in two. Combined kidney/BMT with nonmyeloablative conditioning can achieve renal allograft tolerance and excellent myeloma responses, even in the presence of donor marrow rejection and antidonor alloresponses in vitro.

2005 immunosuppressive strategies in kidney transplantation: which role for the calcineurin inhibitors?

The calcineurin inhibitors (CNIs) cyclosporine and tacrolimus have been the cornerstones of immunosuppressive strategies in clinical transplantation. Currently, regimens that are most widely used for induction and maintenance therapy include CNIs. However, many clinical trials aiming at reducing or eliminating CNIs have been performed in recent years. Here, we review and discuss current and future immunosuppressive strategies with a special emphasis on the role of CNIs, in the light of recent studies in the field of kidney transplantation. In the current era, CNIs still play an important role.

Reproduction and transplantation: report on the AST Consensus Conference on Reproductive Issues and Transplantation

It has been almost 50 years since the first child was born to a female transplant recipient. Since that time pregnancy has become common after transplantation, but physicians have been left to rely on case reports, small series and data from voluntary registries to guide the care of their patients. Many uncertainties exist including the risks that pregnancy presents to the graft, the patient herself, and the long-term risks to the fetus. It is also unclear how to best modify immunosuppressive agents or treat rejection during pregnancy, especially in light of newer agents available where pregnancy safety has not been established. To begin to address uncertainties and define clinical practice guidelines for the transplant physician and obstetrical caregivers, a consensus conference was held in Bethesda, Md. The conferees summarized both what is known and important gaps in our knowledge. They also identified key areas of agreement, and posed a number of critical questions, the resolution of which is necessary in order to establish evidence-based guidelines. The manuscript summarizes the deliberations and conclusions of the conference as well as specific recommendations based on current knowledge in the field.

Prevalence and significance of anti-HLA and donor-specific antibodies long-term after renal transplantation

Post-transplant circulating anti-human leukocyte antigens (HLA)-antibodies and C4d in allograft biopsies may be important in chronic rejection in renal transplant recipients (RTR). We determined the prevalence and significance of anti-HLA-antibodies and donor-specific antibodies (DSA). Sera were collected from 251 RTR >6 months post-transplant. Sera were tested using enzyme-linked immunosorbent assay (ELISA) screening for anti-HLA antibodies. Positive sera were retested with ELISA-specific panel for antibody specificity. A 11.2% of patients had anti-HLA antibodies and 4.4% had DSA. Anti-HLA antibodies were significantly associated with pretransplant sensitization, acute rejection and in multivariate analysis, higher serum creatinine (2.15 +/- 0.98 vs. 1.57 +/- 0.69 mg/dl in negative anti-HLA antibodies group). Allograft biopsies performed in a subset of patients with anti-HLA antibodies revealed that 66% had C4d in peritubular capillaries (0% in patients without antibodies). Anti-HLA antibodies were associated with a worse allograft function and in situ evidence of anti-donor humoral alloreactivity. Long-term RTR with an increase in creatinine could be screened for anti-HLA antibodies and C4d in biopsy.

Hepatitis C, acute humoral rejection, and renal allograft survival

The effect of recipient hepatitis C virus (HCV) infection on renal allograft loss and acute rejection in kidney transplantation remains controversial. We studied 354 renal allograft recipients transplanted during 1996 to 2001 who had HCV antibodies (Ab) measured before transplantation. The primary outcome was death-censored allograft loss and the secondary outcome was acute humoral rejection (AHR). Compared with HCV Ab-negative patients, those with positive HCV Ab had longer time on dialysis before transplantation, higher percentage of panel-reactive antibodies (PRA), were more likely to receive a cadaveric transplant, and were more likely to develop delayed graft function (DGF). In univariate analyses, predictors of renal allograft loss included HCV, cadaveric graft, PRA >20%, HLA mismatch > or =5, retransplantation, DGF, induction therapy, and AHR. When adjusted for PRA >20%, HLA mismatch > or =5, and multiple transplant status, HCV was not a statistically significant predictor of allograft loss. HCV was also associated with AHR but lost significance when adjusted for PRA >20%. HCV Ab-positive patients were more likely to have longer duration of dialysis before transplantation prior to kidney transplants, higher PRA, and to receive cadaveric transplants. These characteristics likely resulted in more DGF and AHR after transplantation. After adjusting for these confounding factors, the association between HCV Ab positivity and renal allograft loss was notably attenuated and no longer statistically significant.

Significance of anticardiolipin antibodies on short and long term allograft survival and function following kidney transplantation

The significance of anticardiolipin antibodies (ACAs) prior to renal transplantation is unclear. We studied a cohort of 337 patients who underwent renal transplantation from 1996 to 2001. Follow-up continued until allograft loss, patient death or 31 December 2002. The primary outcome was a composite endpoint of death-censored allograft loss or a 25% reduction in estimated glomerular filtration rate (GFR) from 1-month post-transplant. Secondary outcomes were allograft loss, a 25% reduction in GFR, acute rejection and creatinine at 1 year. IgG and IgM ACA titers were positive (> or =15) in 18.1% of recipients. There were no significant differences at baseline between recipients, except coumadin therapy in those with positive ACA titers (20% vs. 7.4%). Post-transplant, there was no increase in the primary outcome in ACA-positive patients, even after adjustment for anticoagulation with coumadin (HR = 1.42 [0.68, 2.96]). There was no difference in secondary outcomes between those with or without positive titers. Two of five patients with very high titers (>50) who were not anticoagulated had early graft loss. A positive ACA titer prior to kidney transplantation was not associated with inferior renal outcomes after transplantation, although more research is required to address the prognostic significance of very high ACA titers.

Analysis of the cardiovascular risk profile in stable kidney transplant recipients after 50% cyclosporine reduction

BACKGROUND

Long-term use of cyclosporine (CsA) contributes to post-transplant cardiovascular disease (CVD). Hence, a reduction in CsA dosage in kidney transplant recipients (KTR) may improve long-term outcomes. We analyzed the effects of 50% CsA dose reduction on the CVD risk profile in stable KTR.

METHOD

Thirty-one KTR on a regimen of CsA, prednisone and mycophenolate mofetil (MMF) were studied. Patients were randomized to either a) continue their previously determined CsA dose (control group, n = 15) or b) lower their CsA dose by 50% (CsA reduction group, n = 16). Renal function, blood pressure, lipid profile, plasma homocysteine (HCY), C-reactive protein (CRP), fibrinogen, and uric acid were compared at baseline and at 6 months.

RESULTS

At 6 months, there was a significant improvement in allograft function, systolic blood pressure, number of anti-hypertensive medications and serum uric acid levels in the CsA reduction group. No significant decrease in plasma HCY, CRP, fibrinogen or improvement in lipid profile was found. In contrast, in the Control group, there was a significant increase in HCY, uric acid, and triglycerides. No acute rejection occurred in either group.

CONCLUSIONS

A greater reduction in CsA dose could further improve CVD risk profiles, although this may increase the risk of acute or subclinical rejection.

Interferon-alpha therapy in liver transplant recipients: lack of association with increased production of anti-HLA antibodies

Interferon-alpha (IFN) is a useful treatment for active HCV infection. In kidney transplantation, IFN has been shown to trigger acute rejection with de novo anti-HLA antibodies. Interferon-alpha has not been reported to enhance the risk of acute rejection in HCV-positive liver transplant recipients (LTRs). Sera were collected from 44 LTRs greater than 6 months post-transplant. Sera were tested with ELISA for the presence and the specificity of anti-HLA antibodies. The prevalence of anti-HLA antibodies was 11% and was not significantly different in 13 HCV-positive recipients who received IFN, compared with 10 who did not receive IFN (8% vs. 20%), or with 21 HCV-negative recipients (10%). None of the patients had an acute rejection after starting IFN. In this study, LTRs receiving IFN did not have an increased frequency of anti-HLA antibodies. This may partially explain the safety of IFN previously reported in LTRs requiring antiviral therapy.

A prospective, randomized, clinical trial of intraoperative versus postoperative Thymoglobulin in adult cadaveric renal transplant recipients

BACKGROUND

Delayed graft function (DGF) is frequently observed in recipients of cadaveric renal transplants. Previous retrospective or nonrandomized studies have suggested that intraoperative administration of polyclonal antithymocyte preparations may reduce the incidence of DGF, possibly by decreasing ischemia-reperfusion injury.

METHODS

We performed a prospective randomized study of Thymoglobulin induction therapy in adult cadaveric renal transplant recipients. Between January 2001 and January 2002, 58 adult cadaveric renal transplant recipients were randomized to receive intraoperative or postoperative Thymoglobulin induction therapy. Three to six doses of Thymoglobulin (1 mg/kg/dose) were administered during the first week posttransplant. Baseline immunosuppression consisted of tacrolimus (54 of 58) or cyclosporine A (4 of 58), steroids, and mycophenolate mofetil. DGF was defined by the requirement for hemodialysis within the first week posttransplant.

RESULTS

There were no significant differences between the two groups in recipient demographics, donor age, cold ischemia time, or total number of doses of Thymoglobulin administered. Intraoperative Thymoglobulin administration was associated with significantly less DGF and a lower mean serum creatinine on postoperative days 10 and 14 (P<0.05). Posttransplant length of stay was also significantly shorter for the intraoperative Thymoglobulin patient group. The acute rejection rate was also lower in the intraoperative treatment group but this did not achieve statistical significance. There was no difference in the incidence of cytomegalovirus disease between the two groups.

CONCLUSIONS

The results of this study indicate that intraoperative Thymoglobulin administration, in adult cadaveric renal transplant recipients, is associated with a significant decrease in DGF, better early allograft function in the first month posttransplant, and a decreased posttransplant hospital length of stay.

A prospective, randomized clinical trial of cyclosporine reduction in stable patients greater than 12 months after renal transplantation

BACKGROUND

For stable kidney-transplant recipients receiving triple drug therapy with cyclosporine (CsA), prednisone, and mycophenolate mofetil (MMF), it remains unclear what is the optimal dose of CsA beyond the first 6 to 12 months after transplantation. Complete CsA withdrawal has been associated with a significant incidence of acute rejection and, in some studies, chronic rejection as well.

METHODS

We performed an open, prospectively randomized, controlled clinical trial to determine whether CsA could be safely reduced by 50%. At 1 year or more posttransplant, 64 patients were randomized to either continue their stable-maintenance CsA dose (control group, n=32) or to lower their CsA dose by 50% over a 2 month period (CsA reduction group, n=32). All patients had stable renal-allograft function at the time of enrollment.

RESULTS

Within 6 months of randomization, no episode of acute rejection or graft loss occurred in either group. Patients in the CsA reduction group had a slight but significant increase in their glomerular filtration rate and a trend towards lower serum creatinine. There was also a significant decrease in mean systolic blood pressure, triglycerides, and serum uric acid levels in the CsA reduction group. No significant changes in any of these parameters were observed in the control group.

CONCLUSIONS

This study suggests that a strategy consisting of a 50% CsA reduction is safe and is not associated with the increased risk of acute rejection observed in CsA withdrawal studies. It also has the potential to improve short-term allograft function and appears to reduce cardiovascular risk factors such as hypertension and hyperlipidemia.

The problem of late allograft loss in kidney transplantation

The 2 principal factors implicated in late kidney allograft failure are chronic rejection (also called chronic allograft nephropathy) and death of the patient with a functioning graft (mainly from cardiovascular causes). Despite lifelong immunosuppression of the recipient, immunological responses remain the leading factor in the pathogenesis of chronic rejection and both cellular and humoral immune mechanisms have been shown to play important roles. In this review, we highlight the relevance of humoral mechanisms of rejection to the pathogenesis of late allograft loss. Non immunological factors, such as donor organ quality, initial ischemic injury, calcineurin inhibitor (CNI) toxicity, hypertension, and hyperlipidemia, also contribute to progressive chronic allograft injury, but will not be reviewed in detail here. Possible strategies to stabilize or improve allograft function in patients with already established "chronic rejection/chronic allograft nephropathy" (CR/CAN) are the addition of mycophenolate mofetil (or sirolimus) with or without a reduction of cyclosporine dosage, or conversion from cyclosporine to tacrolimus. However, prospective randomized clinical trials are needed to test the efficacy of these strategies. A major current challenge for transplant physicians is to develop regimens that prevent CR/CAN, since, once established, the process typically progresses inexorably to renal allograft loss in most recipients. Evidence is now accumulating that new immunosuppressive regimens must control not only T cell but also B cell responses (i.e. limit antidonor antibody production) in order to prevent CR/CAN and improve long-term allograft survival.

Acute humoral rejection in hepatitis C-infected renal transplant recipients receiving antiviral therapy

The use of interferon-alpha (IFN) in hepatitis C (HCV)-infected renal recipients has been associated with acute rejection and graft loss. We reviewed our recent experience in HCV (+) renal recipients treated with antiviral therapy for biopsy proven chronic hepatitis C. Twelve HCV (+) recipients who recently received antiviral therapy were analyzed. Post-treatment sera were tested for donor-specific human leukocyte antigen (HLA) antibodies (DSA). Within 6 months of initiating antiviral therapy, two of 12 patients (17%) developed acute rejection, which was characterized as acute humoral rejection (de novo DSA in serum and C4d deposits in peritubular capillaries). Both progressed to graft failure. Nine of the remaining 10 patients tested did not have DSA. The use of IFN was associated with severe acute humoral rejection (C4d +, DSA +). The recognition of IFN-associated acute humoral rejection in this series may explain the high rate of graft loss reported previously in renal recipients receiving IFN.

Induction of kidney allograft tolerance after transient lymphohematopoietic chimerism in patients with multiple myeloma and end-stage renal disease

BACKGROUND

Two patients with end-stage renal disease secondary to multiple myelomas were treated with combined kidney and bone marrow transplantation in an effort to achieve donor-specific allotolerance through the induction of mixed lymphohematopoietic chimerism.

METHODS

Two female patients (55 and 50 years of age) with end-stage renal disease secondary to kappa light-chain multiple myelomas received a nonmyeloablative conditioning regimen that consisted of 60 mg/kg cyclophosphamide intravenously (IV) on days -5 and -4; 15 mg/kg equine anti-thymocyte globulin (ATGAM) IV on days -1, +1, and +3; and thymic irradiation (700 cGy) on day -1. On day 0, the recipients underwent kidney transplantation, followed by IV infusion of donor bone marrow (2.7x10(8) and 3.8x10(8) /kg nucleated cells, respectively) obtained from a human leukocyte antigen (HLA)-matched sibling. Cyclosporine A was administered IV at a dose of 5 mg/kg on day -1, then continued orally at 8 to 12 mg/kg per day until days +73 and +77, respectively, after which no further immunosuppression was given. Donor leukocyte infusions (1x10(7) /kg CD3+ T cells) were administered in an attempt to enhance the graft-versus-myeloma effect (days +66 and +112 in the first patient and day +78 in the second patient). Hematopoietic chimerism was monitored weekly by microsatellite assays.

RESULTS

Multilineage lymphohematopoietic chimerism (5%-80% donor CD3+ or CD3- cells, or both) was first detected during the second posttransplant week and was maintained for approximately 12 weeks, after which there was a gradual decline to undetectable levels (<1% donor cells) after day 105 in the first patient and after day 123 in the second patient. In both recipients, the blood urea nitrogen and creatinine levels returned to normal within 3 days. No rejection episodes have occurred. Quantification of urinary kappa light chains revealed a decline from 28 mg/dL to undetectable levels (<2.5 mg/dL) within 29 days in the first case and from 99.8 mg/dL to <10 mg/dL within 50 days in the second case. Both patients continue with normal kidney function and sustained anti-tumor responses, while receiving no immunosuppression for nearly 4 years and 2 years, respectively.

CONCLUSIONS

This nonmyeloablative regimen followed by combined HLA-matched donor bone marrow and renal allotransplantation is the first example of an intentional and clinically applicable approach to inducing renal allograft tolerance and achieving potent and sustained antitumor effects in patients with multiple myeloma.

The kidney transplant program at the Massachusetts general hospital

Between February 1963 and December 2000, 1,627 kidney transplants were performed at the Massachusetts General Hospital. The majority (62%) were from cadaveric donors, although in recent years (1996-2000) 52% have been allografts from living donors, with an increase in living unrelated donors. The introduction of CsA and OKT3 in 1984 was associated with a significant improvement in actuarial renal allograft survival, although a persistent late attrition of allografts continues beyond the first year after transplantation. As reported in other centers, current actuarial survival for living unrelated allografts is superior to that of cadaveric allografts, and is quite similar to that observed in recipients of non-HLA identical living-related transplants. Our preliminary laparoscopic donor nephrectomy experience is encouraging as excellent allograft survival and function has been observed, with minimal morbidity associated with the procedure and a low rate of conversion to open nephrectomy. Recent changes in immunosuppressive protocols have resulted in lower early acute rejection rates, however the incidence of delayed graft function remains unchanged in cadaveric renal transplantation. The role of humoral immunity in allograft rejection has been progressively clarified and new approaches to control donor specific alloantibody production have been shown to be effective. Current clinical studies are ongoing to determine the optimal type and dose of calcineurin inhibitors beyond the first year after transplantation and to study whether avoidance of steroids is safe and feasible. Finally, an innovative tolerance induction protocol using the mixed chimerism approach has been successfully accomplished in selected patients with end-stage renal disease secondary to multiple myeloma. These encouraging observations emphasize that major changes from current immunosuppressive regimens are likely to occur over the next few years as more approaches to tolerance induction are explored clinically.

Prevalence of renal cell carcinoma in patients with ESRD pre-transplantation: a pathologic analysis

BACKGROUND

Acquired renal cystic disease (ARCD), renal adenoma (AD), and renal cell carcinoma (RCC) are more common in patients with end-stage renal disease (ESRD). However, the prevalence of these conditions in patients undergoing transplantation, and the clinical characteristics associated with their occurrence are unclear.

METHODS

At our institution, the majority of patients undergo an ipsilateral native nephrectomy at the time of transplantation, providing a unique opportunity to study the prevalence and pathology of ARCD, AD and RCC in ESRD. We retrospectively reviewed all consecutive nephrectomy pathology reports over a six year period. Demographic and clinical characteristics associated with these lesions were identified.

RESULTS

Two hundred and sixty nephrectomy reports were reviewed: ARCD, AD, RCC and oncocytoma were found in 33%, 14%, 4.2% and 0.6% of cases, respectively. On multivariable analysis, ARCD was positively associated with male sex and longer dialysis duration and negatively associated with peritoneal dialysis. Similarly, AD was positively associated with male sex, longer dialysis duration and greater age. There was a trend for RCC cases to share similar associations although the small total number of cases precluded findings of statistical significance.

CONCLUSION

By pathologic analysis, renal tumors are more common in the pre-transplant ESRD population than previously reported (using radiologic methods). Our study also identifies risk factors for their occurrence. This may prove useful in designing screening studies for renal tumors in this patient population.

Managing the highly sensitized transplant recipient and B cell tolerance

The detection of anti-donor-HLA antibodies in a renal allograft recipient's serum, either at the time of or after transplantation, is usually associated with specific antibody-mediated clinical syndromes. These can be divided temporally into three categories: hyperacute rejection, acute humoral rejection and chronic humoral rejection. With the identification of new immunosuppressive drug combinations, more-effective control of alloantibody production has been recently achieved in humans. Thus, prevention and/or treatment of antibody-mediated allograft injury are now possible. Ultimately, the induction of mixed hematopoietic chimerism may allow us to overcome the problem of allosensitization and accept an allograft without chronic immunosuppression.