Few studies of wild animal performance account for parasite infections: A systematic review.

Wild animals have parasites. This inconvenient truth has far-reaching implications for biologists measuring animal performance traits: infection with parasites can alter host behaviour and physiology in profound and sometimes counterintuitive ways. Yet, to what extent do studies on wild animals take individual infection status into account? We performed a systematic review across eight scientific journals primarily publishing studies in animal behaviour and physiology over a 5-year period to assess the proportion of studies which acknowledge, treat or control for parasite infection in their study design and/or analyses. We explored whether parasite inclusion differed between studies that are experimental versus observational, conducted in the field vs the laboratory and measured behavioural vs physiological traits. We also investigated the importance of other factors such as the journal, the trait category (e.g. locomotion, reproduction) measured, the vertebrate taxonomic group investigated and the host climatic zone of origin. Our results show that parasite inclusion was generally lacking across recent studies on wild vertebrates. In over 680 filtered papers, we found that only 21.9% acknowledged the potential effects of infections on animal performance in the text, and only 5.1% of studies treated animals for infection (i.e. parasite control) or considered infection status in the statistical analyses (i.e. parasite analysis). Parasite inclusion, control and analysis were higher in laboratory compared to field studies and higher for physiological studies compared to behavioural studies but did not differ among journals, performance trait categories and taxonomic groups. Among climatic zones, parasite inclusion, control and analysis were higher in tropical, subtropical and temperate zones than in boreal and polar zones. Overall, our literature review suggests that parasites are sorely under-acknowledged by researchers in recent years despite growing evidence that infections can modify animal performance. Given the ubiquity of parasites in the environment, we encourage scientists to consider individual infection status when assessing performance of wild animals. We also suggest ways for researchers to implement such practices in both experimental and observational studies.

Increased parasite load is associated with reduced metabolic rates and escape responsiveness in pumpkinseed sunfish.

Wild animals have parasites that can compromise their physiological and/or behavioural performance. Yet, the extent to which parasite load is related to intraspecific variation in performance traits within wild populations remains relatively unexplored. We used pumpkinseed sunfish (Lepomis gibbosus) and their endoparasites as a model system to explore the effects of infection load on host aerobic metabolism and escape performance. Metabolic traits (standard and maximum metabolic rates, aerobic scope) and fast-start escape responses following a simulated aerial attack by a predator (responsiveness, response latency and escape distance) were measured in fish from across a gradient of visible (i.e. trematodes causing black spot disease counted on fish surfaces) and non-visible (i.e. cestodes in fish abdominal cavity counted post-mortem) endoparasite infection. We found that a higher infection load of non-visible endoparasites was related to lower standard and maximum metabolic rates, but not aerobic scope in fish. Non-visible endoparasite infection load was also related to decreased responsiveness of the host to a simulated aerial attack. Visible endoparasites were not related to changes in metabolic traits or fast-start escape responses. Our results suggest that infection with parasites that are inconspicuous to researchers can result in intraspecific variation in physiological and behavioural performance in wild populations, highlighting the need to more explicitly acknowledge and account for the role played by natural infections in studies of wild animal performance.

Humoral and Cellular Immune Responses of Solid Organ Transplant Patients on Belatacept to Three Doses of mRNA-Based Anti-SARS-CoV-2 Vaccine.

BACKGROUND: Two doses of anti-SARS-CoV-2 mRNA-based vaccines are poorly immunogenic in solid organ transplant recipients (SOT). METHODS: In total, 68 belatacept-treated SOT recipients followed at the Toulouse University Hospital were investigated. They were given three injections of the BNT162b2 mRNA COVID-19 vaccine. Their humoral response was assessed by determining anti-spike antibodies and neutralizing antibodies. The T-cell responses were assessed using an enzyme-linked immunospot assay that measured the interferon-γ produced by specific SARS-CoV-2 T-cells in a subgroup of 17 patients. RESULTS: Only 23.5% of these patients developed a detectable anti-spike response. Moreover, the cellular and the humoral responses were well correlated. Patients with no humoral response were also without a detectable cellular response. Those belatacept-treated patients who developed an Anti-SARS-CoV-2 humoral response were younger, had been transplanted for longer, and had a higher lymphocyte count and a better glomerular filtration rate than those with no response. Finally, patients on tacrolimus plus belatacept produced a lower immune response. CONCLUSIONS: Belatacept-treated SOT recipients have a reduced immune response to anti-SARS-CoV-2 mRNA vaccination. The vaccine should be given quite separately from the belatacept infusion to improve immunogenicity. Studies to assess whether switching to another immunosuppressive regimen can improve the post-vaccination immune response would be useful.

Anti-SARS-CoV-2 spike protein and neutralizing antibodies at 1 and 3 months after three doses of SARS-CoV-2 vaccine in a large cohort of solid organ transplant patients.

The immunogenicity of the severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) vaccine was improved by the administration of a third dose. The aim of our retrospective study was to assess the evolution of binding and neutralizing antibody concentration until 3 months after the third dose in a large cohort of solid organ transplant (SOT) patients (n = 872). At 1 month after the third dose, anti-SARS-CoV-2 antibodies were detected by means of enzyme-linked immunosorbent assay tests in 578 patients (66.3%). In a subgroup of patients, 70% (180 out of 257) had anti-SARS-CoV-2 antibody concentrations ranging from 1.2 to 18 411 binding antibody units (BAU)/ml and 48.5% (115 out of 239) had a neutralizing antibodies titer that can confer clinical protection against SARS-CoV-2. Three-hundred ninety-three patients out of the 416 (94.5%) who were seropositive at month 1 and were tested at 3 months after vaccination remained seropositive. Between months 1 and 3 after vaccination, binding and neutralizing antibodies concentrations decreased significantly. The proportion of protected patients against the SARS-CoV-2 also slightly decreased. In conclusion, this study shows that although two-third of SOT develop anti-SARS-CoV-2 antibodies after three doses, one-third of them remain weak or non-protected. It is important to measure anti-SARS-CoV-2 antibodies to define the strategy that can optimize SOT protection against SARS-CoV-2.

Weekly high-dose liposomal amphotericin B prevents invasive aspergillosis after heart transplantation.

BACKGROUND: Preventive strategies for invasive aspergillosis (IA) have still not been determined in heart transplant recipients whereas IA leads to a high mortality rate at 12 months posttransplantation. The use of voriconazole or echinocandins was proposed but can favor emergence of Aspergillus or Candida sp. resistant strains or promote neurological and liver disorders in some patients. OBJECTIVES: To assess whether universal prophylaxis with weekly high-dose of liposomal amphotericin-B (L-AmB) can safely prevent IA in heart transplant recipients. PATIENTS/METHODS: Retrospective before/after study that included 142 patients who received heart transplantation between 2010 and 2019 at the University Hospital of Toulouse (France). Weekly high dose of L-AmB (7.5 mg/kg/week) was used as universal prophylaxis from 2016 because of high environmental exposure to Aspergillus sp. and high incidence of IA. RESULTS: Cumulative 1-year incidence of IA decreased from 23% to 5% after introduction of L-Amb prophylaxis. Multivariate analysis (Cox model) identified L-AmB prophylaxis as a protective factor against IA (hazard ratio [HR] 0.21 [95% confidence interval 0; 0.92], p = .04), whereas postoperative renal replacement therapy was associated with IA (HR 3.6 [95% confidence interval 1.38; 9.3], p = .001), after correction for confounding effects (induction regimen, methylprednisolone pulses and history of hematological malignancy). The incidence of acute kidney injury requiring renal replacement therapy was similar in the two groups, suggesting a low risk of kidney toxicity when L-AmB is used weekly. No patient developed severe kidney electrolyte loss nor L-AmB-related anaphylaxis. CONCLUSIONS: Once-weekly high-dose L-AmB is safe and may prevent the development of IA after heart transplantation.

Impact of right ventricular systolic function after heart transplantation on exercise capacity.

BACKGROUND: Right ventricular (RV) systolic parameters are difficult to assess in heart transplant recipients (HTRs) compared to healthy people because of discordant data, and their impact on exercise capacity remains undefined. We sought to retrospectively assess the impact of RV systolic function on exercise capacity after heart transplantation. METHODS: We analyzed data from 61 HTRs who underwent transthoracic echocardiography (TTE), cardiac magnetic resonance imaging (CMR), and exercise capacity assessment by 6-minute walking test (6MWT) and cardiopulmonary exercise testing (CPET) at 1- and 2-year follow-ups. RESULTS: Transthoracic echocardiography RV longitudinal systolic function including tricuspid annular plan systolic excursion (TAPSE), peak systolic S' wave tricuspid annular velocity (PSVtdi) and RV free wall longitudinal strain was decreased at 1 year (respectively, 15 ± 3 mm, 10 ± 3 cm/s, and -19 ± 5%) and at 2 years (respectively, 15 ± 3 mm, 10 ± 2 cm/s, and -20 ± 5%) with no significant difference between both evaluations; meanwhile, RV ejection fraction (RVEF) measured by CMR was preserved. Mean percentage of predicted peak oxygen consumption was altered, but improved between the first and second year (55 ± 18 vs 60 ± 18%, P = .038). PSVtdi was weakly correlated with 6MWT distance (r = .426, P = .017) and RVEF with the predicted distance at 6MWT (r = .410, P = .027) at the 1-year follow-up. CONCLUSIONS: Despite decreasing values, RV longitudinal systolic function has a weak impact on exercise capacity of HTRs. PSVtdi and RVEF are the most pertinent parameters to assess the impact of RV systolic function on exercise capacity after heart transplantation. These results should lead to redefine normal RV systolic function thresholds for HTRs.

Belatacept-based immunosuppression: A calcineurin inhibitor-sparing regimen in heart transplant recipients.

Belatacept (BTC) is indicated for prophylaxis of graft rejection in adults receiving a renal transplant (Tx). This retrospective observational study (three centers) included all heart transplant recipients receiving BTC between January 2014 and October 2018. Forty EBV+ patients mean GFR 35 ± 20 mL/min/m2 were identified, among whom belatacept was initiated during the first 3 months after transplantation in 12 patients, and later in 28 patients. Several patients were multiorgan transplant recipients. Study outcomes were GFR, safety, and changes in immunosuppressive therapy. The main reason for switching to BTC was to preserve renal function, resulting in discontinuation of CNI and changes in immunosuppressive therapy in 76% of cases. At study closeout, 24/40 patients were still on BTC therapy. GFR was improved (+59%, P = .0002*) within 1 month, particularly in the early group. More episodes of rejection were observed among "late" patients (1 death). Sixteen treatment discontinuations were recorded: GFR recovery (n = 4), DSA no longer detectable (n = 1), compliance issues (n = 3), poor venous access (n = 2), multiple infections (n = 1), 1 death (fungal lung infection), and treatment failure (n = 4). Median follow-up was 24 months. Four patients developed de novo DSA (MFI<1500). BTC is an effective alternative immunosuppressive for postoperative transient kidney failure, stabilizing delayed renal function, with acceptable safety profile under careful monitoring.

Outcomes of solid organ transplant recipients with invasive aspergillosis and other mold infections.

OBJECTIVES: To characterize the clinical presentation and outcomes of invasive mold infections (IMI) in solid organ transplant (SOT) recipients. METHODS: Inclusion of all SOT recipients with IMI diagnosed between 2008 and 2016 at a referral center for SOT. Univariable analyses identified factors associated with death at one year, and logistic regression models retained independent predictors. RESULTS: Of the 1739 patients that received a SOT during this period, 68 developed IMI (invasive aspergillosis [IA] in 58). Cumulative incidence of IMI at 1 year ranged from 1.2% to 18.8% (kidney and heart transplantation, respectively). At baseline, compared with other IMI, the need for vasoactive drugs was more frequent in patients with IA. During follow-up, 35 patients (51%) were admitted to the ICU and required mechanical ventilation (n = 27), vasoactive drugs (n = 31), or renal replacement therapy (n = 31). The need for vasoactive drugs (OR 7.34; P = .003) and a positive direct examination (OR 10.1; P = .004) were independently associated with the risk of death at 1 year in patients with IA (n = 33; 57%) CONCLUSIONS: Characteristics of IMI at presentation varied according to the underlying transplanted organ and the mold species. Following IA, one-year mortality may be predicted by the need for hemodynamic support and initial fungal load.

De novo donor-specific anti-HLA antibodies mediated rejection in liver-transplant patients.

The incidence and consequences of de novo donor-specific anti-HLA antibodies (DSAs) after liver transplantation (LT) are not well known. We investigated the incidence, risk factors, and complications associated with de novo DSAs in this setting. A total of 152 de novo liver-transplant patients, without preformed anti-HLA DSAs, were tested for anti-HLA antibodies, with single-antigen bead technology, before, at transplantation, at 1, 3, 6 and 12 months after transplantation, and thereafter annually and at each time they presented with increased liver-enzyme levels until the last follow-up, that is, 34 (1.5-77) months. Twenty-one patients (14%) developed de novo DSAs. Of these, five patients had C1q-binding DSAs (24%). Younger age, low exposure to calcineurin inhibitors, and noncompliance were predictive factors for de novo DSA formation. Nine of the 21 patients (43%) with de novo DSAs experienced an acute antibody-mediated rejection (AMR). Positive C4d staining was more frequently observed in liver biopsies of patients with AMR (9/9 vs. 1/12, P < 0.0001). Eight patients received a B-cell targeting therapy, and one patient received polyclonal antibodies. Only one patient required retransplantation. Patient- and graft-survival rates did not differ between patients with and without DSAs. In conclusion, liver-transplant patients with liver abnormalities should be screened for DSAs and AMR.

An Early Viral Response Predicts the Virological Response to Ribavirin in Hepatitis E Virus Organ Transplant Patients.

BACKGROUND: Ribavirin is efficient at treating chronic hepatitis E virus infection in solid-organ transplant patients. However, the early kinetics of viral replication under therapy and the impact of immunosuppressant regimens on viral replication are unknown: thus, determining the aim of our study. METHODS: Thirty-five patients with a solid-organ transplant and chronic hepatitis E virus infection were given ribavirin for 3 months. The hepatitis E virus (HEV) RNA concentrations were determined before treatment, at days 7, 15, and 21 and at months 1, 2, and 3 during therapy and after ribavirin cessation. RESULTS: A sustained virological response (SVR) occurred in 63%. Decreased viral concentration within the first week post-ribavirin therapy was an independent predictive factor for SVR, and a decreased HEV concentration of 0.5 log copies/mL or greater had an 88% positive predictive value. No correlation between ribavirin trough level on day 7 or at month 2 with a virological response or an SVR was observed. Before therapy, HEV RNA concentration was significantly greater in patients receiving mechanistic target of rapamycin inhibitor-based immunosuppression compared to patients given calcineurin inhibitors. The use of mycophenolic acid did not impact on the response to ribavirin. CONCLUSION: An early response to ribavirin can be used to define the optimal duration of therapy in the setting of HEV infection.

Prospective monitoring of cytomegalovirus, Epstein-Barr virus, BK virus, and JC virus infections on belatacept therapy after a kidney transplant.

OBJECTIVES: Few data regarding viral replication in patients receiving belatacept are available. The aim of this single-center study was to compare the incidence of viral infections (cytomegalovirus, Epstein Barr virus, BK virus, and JC virus), in 62 de novo kidney transplant patients enrolled in the BENEFIT studies, receiving either belatacept (n=42) or cyclosporine (n=20). MATERIALS AND METHODS: By means of polymerase chain reaction, belatacept-treated patients were tested for cytomegalovirus, Epstein-Barr virus, BK virus, and JC virus infections monthly for 36 months, monthly for the first 6 months, and then quarterly for 36 months in cyclosporine-treated patients. Additional samples were obtained when a viral infection was suspected. RESULTS: The number of positive cytomegalovirus, BK virus, or JC virus viremias over the number of polymerase chain reactions performed through all 3 years was similar in both groups. Conversely, over the 3-year study, the number of positive Epstein-Barr virus viremias over the number of Epstein-Barr virus polymerase chain reactions performed was significantly higher in the belatacept group (76% vs 50%; P = .047). The number of Epstein-Barr virus primary infection was similar in both groups, while the number of Epstein-Barr virus reactivation was higher in the belatacept group. CONCLUSIONS: Epstein-Barr virus replication occurs more often in patients receiving belatacept, than it does in those receiving cyclosporine.

Rituximab for minimal-change nephrotic syndrome in adulthood: predictive factors for response, long-term outcomes and tolerance.

BACKGROUND: Minimal-change nephrotic syndrome (MCNS) is a common cause of steroid sensitive nephrotic syndrome (NS) with frequent relapse. Although steroids and calcineurin inhibitors (CNIs) are the cornerstone treatments, the use of rituximab (RTX), a monoclonal antibody targeting B cells, is an efficient and safe alternative in childhood. METHODS: Because data from adults remain sparse, we conducted a large retrospective and multicentric study that included 41 adults with MCNS and receiving RTX. RESULTS: Complete (NS remission and withdrawal of all immunosuppressants) and partial (NS remission and withdrawal of at least one immunosuppressants) clinical responses were obtained for 25 and 7 patients, respectively (overall response 78%), including 3 patients that only received RTX and had a complete clinical response. After a follow-up time of 39 months (6-71), relapses occurred in 18 responder patients [56%, median time 18 months (3-36)]. Seventeen of these received a second course of RTX and then had a complete (n = 13) or partial (n = 4) clinical response. From multivariate analysis, on-going mycophenolate mofetil (MMF) therapy at the time of RTX was the only predictive factor for RTX failure [HR = 0.07 95% CI (0.01-0.04), P = 0.003]. Interestingly, nine patients were still in remission at 14 months (3-36) after B-cell recovery. No significant early or late adverse event occurred after RTX therapy. CONCLUSIONS: RTX is safe and effective in adult patients with MCNS and could be an alternative to steroids or CNIs in patients with a long history of relapsing MCNS.

Pregnancy after kidney transplantation: outcome and anti-human leucocyte antigen alloimmunization risk.

BACKGROUND: Kidney transplantation increases the chances for pregnancy and live birth for women with end-stage kidney disease. The aims of this study were to describe the outcomes of pregnancies in women with a kidney transplant and to evaluate the impact on anti-human leucocyte antigen (HLA) alloimmunization. METHODS: We analysed 61 pregnancies that occurred in 46 patients after having excluded 10 miscarriages during the first trimester and 10 other pregnancies from which important data were missing. Anti-HLA antibodies were screened using the Luminex assay. RESULTS: Overall, the live birth rate was 83% (94% after exclusion of miscarriages during the first trimester). Pre-eclampsia and gestational diabetes occurred in 26 and 21% of cases, respectively. The use of tacrolimus was an independent predictive factor for gestational diabetes. Twenty-four newborns (42%) were premature (<37 weeks). The median birth weight was 2720 (1040-3730) g. Nine newborns (15%) had low birth weights (<2.5 kg). At least one severe complication occurred in 56% of pregnancies. A high glomerular-filtration rate (GFR) before pregnancy was the sole independent protective factor that avoided a severe complication. Death-censored kidney-allograft survival was 80.4% at 6 years. De novo donor-specific anti-HLA antibodies were detected after only 5.9% of pregnancies: for two women, the father had the same HLA antigens as those from the deceased organ donor. The determination of the HLA of the father before pregnancy can better inform the woman about the possible impact of pregnancy on her kidney-allograft function. CONCLUSIONS: Despite many complications, the outcomes for pregnancy and kidney allografts are good. The risk of anti-HLA alloimmunization was low.

An unexpected diagnosis in a renal-transplant patient with proteinuria treated with everolimus: AL amyloidosis.

Proteinuria is an expected complication in transplant patients treated with mammalian target of rapamycin inhibitors (mTOR-i). However, clinical suspicion should always be supported by histological evidence in order to investigate potential alternate diagnoses such as acute or chronic rejection, interstitial fibrosis and tubular atrophy, or recurrent or de novo glomerulopathy. In this case we report the unexpected diagnosis of amyloidosis in a renal-transplant patient with pre-transplant monoclonal gammapathy of undetermined significance who developed proteinuria after conversion from tacrolimus to everolimus.

Incidence of donor-specific antibodies in kidney transplant patients following conversion to an everolimus-based calcineurin inhibitor-free regimen.

Scarce data exist regarding the incidence of donor-specific antibodies (DSAs) in kidney transplant patients receiving everolimus-based immunosuppression without calcineurin inhibitors (CNIs). The aim of this retrospective case-control study was to compare the incidence of de novo DSAs in patients converted to an everolimus-based regimen without CNIs with that seen in patients maintained on CNIs. Sixty-one DSA-free kidney transplant patients who had been converted to an everolimus-based regimen (everolimus group) were compared to 61 other patients maintained on CNIs-based regimen (control group). Patients were matched according to age, gender, induction therapy, date of transplantation, and being DSA-free at baseline. At last follow-up, the incidence of DSAs was 9.8% in the everolimus group and 5% in the control group (p = ns). In the everolimus group, the increased incidence of DSAs between baseline and last follow-up was statistically significant. Antibody-mediated rejection occurred in 6.5% in the everolimus group and 0% in the CNIs group. The incidence of DSAs is numerically increased in kidney transplant patients treated with an everolimus-based without CNIs. A study including a larger number of patients is required to determine whether a CNI-free everolimus-based immunosuppression significantly increases DSAs formation.

Systematic kidney biopsies after acute allograft pyelonephritis.

OBJECTIVES: Scarce data exist regarding the effect of acute graft pyelonephritis on kidney histology after a kidney transplant. This study sought to assess the kidney histology at 1 month, and kidney function at 1 year, after acute graft pyelonephritis in kidney transplant patients. MATERIALS AND METHODS: All kidney transplant patients with acute graft pyelonephritis between October 2006, and December 2008, underwent a kidney biopsy 1 month later (n=28). Histologic findings were compared with those observed in a control group (n=28) who underwent a protocol kidney biopsy at 1 year posttransplant and did not present with acute graft pyelonephritis. Patients were matched according to age, sex, and immunosuppressive regimen. RESULTS: Kidney function was impaired by the acute graft pyelonephritis episodes at the time of biopsy. In 40% of patients, the estimated glomerular filtration rate did not return to baseline by 1 month after acute graft pyelonephritis and remained impaired thereafter. Three patients had features of acute rejection. Tubulitis was seen more frequently in the acute graft pyelonephritis group, especially in patients in whom estimated glomerular filtration rate did not completely recover by 1 month after acute graft pyelonephritis. Patients with acute graft pyelonephritis who had inflammatory infiltrate of > 20% 1 month after acute graft pyelonephritis had worse kidney function 1 year later. CONCLUSIONS: After transplant, when kidney function remains impaired 1 month after acute graft pyelonephritis, kidney biopsies allowed graft rejection diagnosis and predicted kidney function recovery.

Do kidney histology lesions predict long-term kidney function after liver transplantation?

Histological renal lesions observed after liver transplantation are complex, multifactorial, and interrelated. The aims of this study were to determine whether kidney lesions observed at five yr after liver transplantation can predict long-term kidney function. Ninety-nine liver transplant patients receiving calcineurin inhibitor (CNI)-based immunosuppression, who had undergone a kidney biopsy at 60±48 months post-transplant, were included in this follow-up study. Kidney biopsies were scored according to the Banff classification. Estimated glomerular filtration rate (eGFR) was assessed at last follow-up, that is, 109±48 months after liver transplantation. eGFR decreased from 92±33 mL/min at transplantation to 63±19 mL/min after six months, to 57±17 mL/min at the kidney biopsy, to 54±24 mL/min at last follow-up (p<0.0001). At last follow-up, only three patients required renal replacement therapy. After the kidney biopsy, 13 patients were converted from CNIs to mammalian target of rapamycin inhibitors, but no significant improvement in eGFR was observed after conversion. Elevated eGFR at six months post-transplant and a lower fibrous intimal thickening score (cv) observed at five yr post-transplant were the two independent predictive factors for eGFR≥60 mL/min at nine yr post-transplant. Long-term kidney function seems to be predicted by the kidney vascular lesions.

Donor-specific antibodies after ceasing immunosuppressive therapy, with or without an allograft nephrectomy.

BACKGROUND AND OBJECTIVES: Within the last few years, anti-human leukocyte antigen detection assays have significantly improved. This study asked, using the Luminex single-antigen assay, whether an allograft nephrectomy allowed donor-specific alloantibodies to appear that were not previously detected in the serum when the failed kidney was still in place. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: After losing the kidney allograft and stopping immunosuppressive therapy, the proportions of donor-specific alloantibodies and nondonor-specific alloantibodies were compared in patients who had (n=48; group I) and had not (n=21; group II) undergone an allograft nephrectomy. Allograft nephrectomies were performed at 150 days after kidney allograft loss, and the time between allograft nephrectomy and last follow-up was 538 ± 347 days. RESULTS: At kidney allograft loss, donor-specific alloantibodies were detected in three group II patients (14.2%) and six group I patients (12.5%). At last follow-up, donor-specific alloantibodies were detected in 11 patients (52.4%) without and 39 patients (81%) with an allograft nephrectomy (P=0.02). Anti-human leukocyte antigen class I donor-specific alloantibodies were positive in 23.8% of group II and 77% of group I patients (P<0.001); anti-human leukocyte antigen class II donor-specific alloantibodies were positive in 42.8% of group II and 62.5% of group I patients. Independent predictive factors for developing donor-specific alloantibodies after losing kidney allograft and stopping immunosuppressants were number of anti-human leukocyte antigen A/B mismatches at transplantation (zero versus one or more) and allograft nephrectomy. CONCLUSIONS: The development of donor-specific alloantibodies was significantly greater in patients with a failed kidney who had undergone an allograft nephrectomy compared with those patients who had not undergone allograft nephrectomy.