Higher calcineurin inhibitor levels predict better kidney graft survival in patients with de novo donor-specific anti-HLA antibodies: a cohort study.

The development of de novo anti-HLA donor-specific antibodies (dnDSA) is associated with poorer outcomes in kidney transplant recipients. Despite this, antibody screening post-transplant is not widespread, largely because the optimal management of patients with dnDSA remains undetermined. We hypothesized that in this population, calcineurin inhibitor blood levels would be an independent predictor of graft loss. We analyzed a cohort of unsensitized patients for whom anti-HLA antibody screening was performed prospectively post-transplant. During the screening period between January 2005 and April 2016, 42 patients developed dnDSA. There was no difference in the clinical characteristics or the histological scores of patients biopsied for clinical indication versus those biopsied solely due to detection of dnDSA. Cox modeling revealed a strong relationship between mean tacrolimus levels following dnDSA detection and graft loss, with a hazard ratio of 0.49 (95% CI, 0.33-0.75), which persisted following adjustment for established independent predictors (HR, 0.52, 95% CI, 0.30-0.89). Kaplan-Meier analysis by tertiles of tacrolimus levels and receiver operating curve analysis concurred to show that a threshold of 5.3 ng/ml could be predictive of graft loss. These data suggest that anti-HLA antibody monitoring post-transplant could guide maintenance immunosuppression and improve graft outcomes.

Impact of donor age on long-term outcomes after delayed graft function: 10-year follow-up.

Delayed graft function (DGF) has a negative impact on graft survival in donation after brain death (DBD) but not for donation after cardiac death (DCD) kidneys. However, older donor age is associated with graft loss in DCD transplants. We sought to examine the interaction between donor age and DGF in DBD kidneys. This is a single-center, retrospective review of 657 consecutive DBD recipients transplanted between 1990 and 2005. We stratified the cohort by decades of donor age and studied the association between DGF and graft failure using Cox models. The risk of graft loss associated with DGF was not significantly increased for donor age below 60 years (adjusted hazard ratio [aHR] 1.12, 1.51, and 0.90, respectively, for age <40, 41-50 and 51-60 years) but significantly increased after 60 years (aHR 2.67; P = 0.019). Analysis of death-censored graft failure yielded similar results for donor age below 60 years and showed a substantially increased risk with donors above 60 years (aHR 6.98, P = 0.002). This analysis reveals an unexpectedly high impact of older donor age on the association between DGF and renal transplant outcomes. Further research is needed to determine the best use of kidneys from donors above 60 years old, where DGF is expected.

Impact of the Current Versus the Previous Diagnostic Threshold on the Outcome of Patients With Borderline Changes Suspicious for T Cell-mediated Rejection Diagnosed on Indication Biopsies.

BACKGROUND: Since the borderline changes suspicious for acute T cell-mediated rejection (BL) category was broadened, there has been a debate regarding the right threshold for tubulitis and interstitial inflammation scores. METHODS: We studied a first cohort of 111 patients with BL found on an indication biopsy between 2006 and 2016 and compared those with scores of t1i0 (BLt1i0) to those with higher scores (BL≥t1i1). A second cohort of 56 patients with BL was used for external validation. We used a composite endpoint of death-censored graft failure or doubling of the serum creatinine level postbiopsy. RESULTS: In the first cohort, 68% (75/111) of the BL cases fell in the BLt1i0 group. At 5 years, the occurrence of the composite endpoint was 5% and 14% for BLt1i0 and BL≥t1i1, respectively. In contrast, the endpoint occurred in 5% of nonrejectors and 21% of patients with T cell-mediated rejection. In the validation cohort, 8% versus 36% of BLt1i0 and BL≥t1i1 reached the endpoint, respectively. Multivariable Cox modeling revealed that BLt1i0 patients had a prognosis similar to that of nonrejectors (adjusted hazard ratio, 0.6; 95% confidence interval, 0.1-2.2; P = 0.40) but better than that of patients with BL≥t1i1 (hazard ratio, 3.8; 95% confidence interval, 1.3-11.5; P = 0.02). Sensitivity analyses restricted to death-censored graft loss or using time posttransplant as the time of reference provided similar results. CONCLUSIONS: In summary, patients with BLt1i0 have a different prognosis to that of BL≥t1i1 patients, which brings into question the current diagnostic thresholds.

Donor-specific antibodies, C4d and their relationship with the prognosis of transplant glomerulopathy.

BACKGROUND: Transplant glomerulopathy (TG) is a diagnostic criterion for chronic active antibody-mediated rejection (CAABMR), with C4d, donor-specific antibodies (DSA) and other lesions of chronic tissue injury. However, TG often presents without C4d or DSA. Until recently, such cases were termed suspicious for CAABMR, and their prognosis remains unclear. METHODS: To better understand the contribution of TG, C4d, and DSA on outcomes, we retrospectively studied 61 patients with late TG for the composite endpoint of death-censored graft failure or doubling of serum creatinine. Cases were matched to controls based on age, year and number of transplant, type of donor, and the availability of an indication biopsy during the same time after transplantation. Analyses were performed using proportional hazards models. RESULTS: Compared to matched controls, patients with TG had a more than fivefold increased risk of reaching the endpoint (adjusted hazard ratio (aHR), 5.3; 95% confidence interval (95% CI), 1.5-18.4). The proportion of patients with isolated TG, TG suspicious for CAABMR (C4+/DSA- or C4d-/DSA+) and TG with definite CAABMR (C4d+/DSA+) were 63%, 20%, and 17%, respectively. Suspicious and definite CAABMR showed a similar prognosis, significantly worse than isolated TG (aHR, 4.5; 95% CI, 1.1-18.9 and aHR, 5.9, 95% CI, 1.1-31.3 respectively). CONCLUSION: Transplant glomerulopathy is associated with poor prognosis, independent of the level of graft dysfunction and other chronic histologic changes. This prognosis is similar whether there is evidence of tissue or peripheral alloantibody reactivity. These findings are relevant to the development of clinically meaningful criteria for CAABMR, for its clinical management, and in the future selection of population for clinical trials.

Endothelin-1 levels and cardiovascular risk factors in renal transplant patients.

OBJECTIVE: Circulating endothelin-1 (ET-1) levels have been reported to be associated with vascular complications and endothelial dysfunction in nontransplanted patients. The aim of this study was to investigate the relationship between ET-1 levels and major cardiovascular (CV) risk factors in renal transplant (RTX) patients with stable graft function. METHODS: ET-1 levels were determined in 156 RTX patients and the relationship between circulating ET-1 levels and CV risk factors including age, gender, kidney function, blood lipids, diabetes, and hypertension was studied. RESULTS: Circulating ET-1 levels were found to be positively correlated with creatinine (r = 0.25, p < 0.01) and systolic blood pressure (r = 0.20, p < 0.05) and inversely correlated with high-density lipoprotein cholesterol (HDL-C) levels (r = -0.27, p < 0.01). Patients with high and intermediate total cholesterol/HDL-C ratios (TC/HDL-C) had significantly higher ET-1 levels when compared to patients with low ratios (7.02 +/- 3.74, 6.79 +/- 2.67, and 5.37 +/- 3.04 pg/ml, respectively, p < 0.002). Only creatinine, HDL-C, and age >40 years were shown to be independent correlates for ET-1 levels according to multivariate analyses. Interestingly, ET-1 levels were significantly higher (+26%, p < 0.03) in RTX patients with documented CV disease, as compared to those without, when matched for age, gender, and presence of diabetes. CONCLUSIONS: Increased circulating ET-1 levels are associated with low HDL-C and documented CV disease in RTX. This is likely a reflection of vascular endothelial damage and dysfunction and therefore may represent an increased risk for atherosclerosis.

Intralesional cidofovir in the treatment of cutaneous warts in a renal transplant patient.

BACKGROUND: Cutaneous warts are often recalcitrant to conventional therapy in immunocompromised patients. Cidofovir is a potent antiviral agent shown to have a broad spectrum of action against DNA virus, including human papillomavirus. OBJECTIVE: To determine the efficacy of intralesional cidofovir in the treatment of florid warts in an immunocompromised renal transplant patient. METHOD: The patient received seven injections of intralesional cidofovir at 4 week intervals in his numerous palmar warts. CONCLUSION: Based on our results, intralesional cidofovir is a promising therapeutic modality in the treatment of cutaneous warts in the renal transplant population.

Dual-kidney transplants as an alternative for very marginal donors: long-term follow-up in 63 patients.

BACKGROUND: Organ shortage has led to the use of dual-kidney transplant (DKT) of very marginal donors into a single recipient to increase the use of marginal organs. To date, few data are available about the long-term outcome of DKT and its usefulness to increase the pool of available organ. METHODS: We conducted a single-center cohort study of DKTs with longitudinal follow-up over an 8-year period. Between 1999 and 2007, 63 DKTs were performed. All kidneys from donors younger than 75 years refused by all centers for single transplantation, and kidneys from donors aged 75 years or older were routinely evaluated based on preimplantation glomerulosclerosis. Renal function, patient or graft survival, and perioperative complications were compared with 66 single kidneys from expanded criteria donors (ECD) and 63 ideal kidney donors. RESULTS: After a median follow-up of 56 months, patient or graft survival was similar between the three groups. Twelve-, 36-, and 84-month creatinine clearance were similar for DKT and ECD (12 months: 58 and 59 mL/min; 36 months: 54 and 60 mL/min; and 84 months: 62 and 51 mL/min, respectively). For the study period, the routine evaluation of very marginal kidneys for DKT in our center has led to an increase of 47% in the transplants from donors aged 50 years or older, which represent 12% at the level of our organ procurement organization. CONCLUSIONS: DKT patients can expect long-term results comparable with single kidney ECD. The implementation of a DKT program in our unit safely increased the pool of organs from marginal donors.

Effects of prednisone withdrawal on the new metabolic triad in cyclosporine-treated kidney transplant patients.

BACKGROUND: Cardiovascular disease is a major cause of morbidity and mortality after renal transplantation. Prednisone (Pred) maintenance therapy is associated with risk factors for atherosclerosis. Therefore, we were interested in quantifying the effects of Pred withdrawal on body weight and waist circumference as well as on metabolic markers of coronary heart disease risk. METHODS: Twenty-six cyclosporine-treated renal transplant patients (13 men and 13 women) were evaluated before and after at least 11 months (16 +/- 2.9 months) of Pred withdrawal. A complete fasting lipoprotein-lipid profile as well as anthropometric measurements were obtained from each patient. RESULTS: Pred withdrawal was associated with a 6.0% reduction of body weight (-4.34 +/- 5.40 kg; P < 0.05) and with a 7.7% decrease in waist girth (-7.13 +/- 5.75 cm; P < 0.005) in women, whereas no change in these variables were observed in men. In both genders, plasma low-density lipoprotein (LDL) cholesterol and triglyceride concentrations were unaffected by Pred withdrawal, whereas plasma high-density lipoprotein (HDL) cholesterol levels decreased by 14.0% in women (-0.22 +/- 0.22 mmol/L; P < 0.005) and 22.0% in men (-0.36 +/- 0.28 mmol/L; P < 0.005). Pred withdrawal was associated with a significant reduction in plasma apolipoprotein B concentrations in both women (-0.28 +/- 0.15 g/L; -24.6%; P < 0.0001) and men (-0.22 +/- 0.19 g/L; -20.5%; P < 0.005). A significant reduction in fasting insulin was observed in both women (-27.8 +/- 27.9 pmol/L; -25.3%; P < 0.005) and men (-25.0 +/- 32.8 pmol/L; -21.4%; P < 0.05), whereas the LDL peak particle size was unaffected by Pred withdrawal. CONCLUSIONS: Pred withdrawal modifies several anthropometric and metabolic cardiovascular risk factors in renal transplant patients. Furthermore, female patients may derive further benefits of Pred withdrawal resulting from the concomitant loss of body weight and abdominal fat.