De novo collapsing glomerulopathy after kidney transplantation: Description of two cases.

BACKGROUND: Among different forms of de novo focal segmental glomerulosclerosis (FSGS), which can develop after kidney transplantation (KTx), collapsing glomerulopathy (CG) is the least frequent variant, but it is associated with the most severe form of nephrotic syndrome, histological findings of important vascular damage, and a 50% risk of graft loss. Here, we report two cases of de novo post-transplant CG. CLINICAL PRESENTATION: A 64-year-old White man developed proteinuria and worsening of renal function 5 years after KTx. Before the KTx, the patient was affected by an uncontrolled resistant hypertension, despite multiple antihypertensive therapies. Blood levels of calcineurin inhibitors (CNIs) were stable, with intermittent peaks. Kidney biopsy showed the presence of CG. After introduction of angiotensin receptor blockers (ARBs), urinary protein excretion progressively decreased in 6 months, but subsequent follow-up confirmed a progressive renal function decline. A 61-year-old White man developed CG 22 years after KTx. In his medical history, he was hospitalized twice to manage uncontrolled hypertensive crises. In the past, basal serum cyclosporin A levels were often detected above the therapeutic range. Low doses of intravenous methylprednisolone were administered due to the histological inflammatory signs shown on renal biopsy, followed by a rituximab infusion as a rescue therapy, but no clinical improvement was seen. DISCUSSION AND CONCLUSION: These two cases of de novo post-transplant CG were supposed to be mainly caused by the synergic effect of metabolic factors and CNI nephrotoxicity. Identifying the etiological factors potentially responsible for de novo CG development is essential for an early therapeutic intervention and the hope of better graft and overall survival.

Hemolytic uremic syndrome and kidney transplantation in uncontrolled donation after circulatory death (DCD): A two-case report.

BACKGROUND: Hemolytic uremic syndrome (HUS) is a rare disease characterized by microangiopathic hemolysis, thrombocytopenia, and renal involvement. Complement-mediated atypical HUS (aHUS) is a result of genetic defects in the alternative complement pathway components or regulators. The introduction of eculizumab has improved renal and overall survival of aHUS patients. Nowadays, given organ shortage, it is necessary to consider kidney transplantation (KT) even in protocols with a high risk of HUS recurrence, such as from donation after circulatory death (DCD) donors. Here, we describe two patients with HUS who underwent a KT from an uncontrolled DCD (uDCD). CASE SUMMARY: The first patient, affected by aHUS due to a heterozygous deletion in CFHR3-CFHR1 and a novel heterozygous variant in CFHR5 gene, underwent a KT with eculizumab prophylaxis. The patient did not experience a post-transplant aHUS recurrence. The second patient, who experienced an HUS episode characterized by a hypertensive crisis and with no underlying mutations in complement system genes, underwent a KT without eculizumab prophylaxis. At day 5, anti-complement treatment commenced due to hematological signs of thrombotic microangiopathy (TMA). After the introduction of eculizumab, we observed a stabilization of kidney function and hematological remission. CONCLUSION: We present herein two different patients with HUS who both underwent successful KT from uDCD donation under the umbrella of eculizumab therapy. Taking into account the importance of increasing the number of organs available for transplantation, uDCD could represent an additional resource in this subset of HUS patients.

Posttransplant outcome of atypical haemolytic uraemic syndrome in a patient with thrombomodulin mutation: a case without recurrence.

Atypical haemolytic uraemic syndrome (aHUS) is a rare disease characterized by thrombocytopenia, microangiopathic haemolytic anaemia and renal impairment. Mutations in genes encoding inhibitors of the alternative pathway of the complement system are involved in ∼50% of the cases. Thrombomodulin (THBD) gene mutations occur in ∼3-5% of the cases. The risk of aHUS recurrence after kidney transplantation depends on the complement abnormality involved. In all three cases of THBD mutation reported to date, aHUS recurred after kidney transplantation (KT) with early graft loss. No data exist about therapeutic approaches before kidney transplantation to reduce the risk of recurrence in patients carrying this mutation. Favourable data on the use of eculizumab have been reported, in terms of plasmatherapy withdrawal and renal function recovery in aHUS recurrence after KT. To our knowledge, this case report presents the first case of successful kidney transplantation in a patient with aHUS due to THBD mutation who was treated with a single plasma-exchange immediately before surgery without recurrence of the disease 12 months after transplantation.

Anti-human leukocyte antigen DQ antibodies in renal transplantation: Are we underestimating the most frequent donor specific alloantibodies?

The role of anti-human leukocyte antigens DQ region (HLA-DQ) in transplantation is historically less studied than HLA-DR and HLA class I regions, but several studies are demonstrating that anti HLA-DQ antibodies are among the most frequent anti HLA antibodies that develop after transplantation and can have great influence on the developing of humoral rejection and graft loss. In this article we review the gene structure and nomenclature of the HLA-DQ region, the role of anti HLA-DQ antibodies after and before transplantation and briefly the associations of particular HLA-DQ alleles and other diseases.

Impact of the pre-transplant histological score on 3-year graft outcomes of kidneys from marginal donors: a single-centre study.

BACKGROUND: The reliability of kidney biopsy as the sole means for assessing kidneys from extended-criteria donors (ECDs) to be allocated to single or dual transplantation is still a matter of debate. METHODS: We compared retrospectively 3 years graft survival and renal function in 44 recipients of a single kidney graft from a marginal donor with good renal function and a Karpinski histological score of ≤ 3 and 56 recipients of a single transplant with a Karpinski score of 4 or 5. The donors' and recipients' characteristics were compared by means of Wilcoxon's rank-sum test and Fisher's exact test, and survival was analysed using the log-rank test and Cox regression survival analysis. RESULTS: The donors with the worse histological scores were slightly younger (68.0 ± 4.74 versus 71.3 ± 4.6 years, P < 0.01) and had a higher glomerular filtration rate (85.8 ± 28.2 versus 76.3 ± 26.53 mL/min, P = 0.013), but there was no difference in serum creatinine levels (0.83 ± 0.24 versus 0.85 ± 0.30 mg/dL, P = 0.381). Three years after transplantation, there was no difference between the two groups in terms of recipient serum creatinine levels (1.94 ± 0.69 versus 1.74 ± 0.49 mg/dL, P = 0.134), estimated glomerular filtration rate (eGFR, 45.6 ± 21.1 versus 51.7 ± 22.0 mL/min, P = 0.331) or the rates of graft loss (27.3 versus 35.7%, P = 0.47), delayed graft function or acute rejection. CONCLUSIONS: In our experience, provided the donor has a normal renal function, a difference in the pre-transplant histological score of kidneys from marginal cadaveric donors do not have a significant influence on the outcome 3 years after transplantation. Our findings might represent a basis for designing a randomized controlled trial of using a higher histological score threshold for the DKT allocation of grafts from ECDs with a normal renal function.

Everolimus leads to a lower risk of BKV viremia than mycophenolic acid in de novo renal transplantation patients: a single-center experience.

BACKGROUND: There are limited published data concerning the effects of different immunosuppressive regimens on the development of polyomavirus (BKV) viremia. We examined the risk of developing BKV viremia in kidney transplant recipients receiving everolimus (EVR) or mycophenolic acid (MPA) as maintenance therapy. METHODS: We observationally analyzed 296 patients who underwent renal transplantation at our center between 2005 and 2010: 58 were treated with EVR and low-dose cyclosporine (LD-CyA) (group 1) and 238 with MPA and standard-dose CyA (group 2). All of the patients received induction therapy with basiliximab and maintenance steroids. BKV viremia (a whole-blood viral load of >850 copies/mL) was measured by means of real-time polymerase chain reaction at least once a month during a 12-month follow-up period. RESULTS: BKV viremia was detected in 57 patients (19%), five (9%) in group 1 and 52 (22%) in group 2. Kaplan-Meier analyses showed that freedom from BKV viremia was significantly more frequent in group 1. The mean time of onset of BKV viremia was about four months after transplantation in both groups. The median viral load was greater in group 2 (12.5 ± 6.1 vs. 2.5 ± 1.8 × 10(4) copies/mL; p = 0.01). After the onset of BKV viremia, graft function significantly declined in group 2: 11 patients developed polyomavirus-associated nephropathy (PVAN) and four presumptive PVAN; nine experienced an acute rejection after the discontinuation of MPA, and 11 (21%) lost their graft. There was no graft loss in group 1. CONCLUSION: These findings suggest that in comparison with MPA and Cya, an EVR and LD-CyA regimen lowers the risk of BKV viremia after kidney transplantation and favorably alters outcomes.

Good outcomes with cyclosporine very low exposure with everolimus high exposure in renal transplant patients.

INTRODUCTION: The aim of the study was to compare efficacy of cyclosporine (CsA) very low exposure with everolimus high exposure, with respect to CsA standard exposure with enteric-coated mycophenolate sodium (EC-MPS) therapy. METHODS: In a randomized, prospective, single-center, open-label study, patients were enrolled to receive either everolimus (C0 (trough level) 8-12 ng/mL) + CsA (C2 (CsA level 2 hours after drug administration) 250-300 ng/mL) + steroids, or EC-MPS (1,440 mg/day) + CsA (C2 500-700 ng/mL) + steroids. Fifty-six patients were enrolled in the everolimus group, 50 in the EC-MPS group. Efficacy was evaluated at 3 and 12 months. RESULTS: Characteristics of groups were similar. Biopsy-proven acute rejection (BPAR) rates were similar in both groups (everolimus 18.8% vs. EC-MPS 18.2%). Everolimus patients had a lower incidence of delayed graft function (DGF) than EC-MPS patients (22.6% vs. 40.9%; p<0.05; relative risk [RR] = 0.65). One-year graft survival was 95% in the everolimus group and 88% in the EC-MPS group (p=NS). CsA dose at 1 year was lower in the everolimus group (1.52 ± 0.67 vs. 2.55 ± 0.79 mg/kg; p<0.0001). Estimated glomerular filtration rate (eGFR; Cockcroft-Gault) was higher in the everolimus group (81.64 ± 32.67 vs. 62.62 ± 22.81 ml/min; p<0.001). Systolic blood pressure was lower in the everolimus group (124.9 ± 14.64 mm Hg vs. 131.1 ± 13.23 mm Hg; p=0.03). Hemoglobin blood levels were slightly lower in the everolimus group (12.62 ± 1.42 vs. 13.01 ± 1.3 g/L; p=NS; for anemia, RR=1.302). Serum cholesterol was similar in both groups (everolimus 219.1 ± 47.20 vs. EC-MPS 207.2 ± 38.8 mg/dL; p=NS), but everolimus patients used more statins (RR=1.49). Twenty-four-hour proteinuria was higher in the everolimus group (519.7 ± 77.31 vs. 296.7 ± 33.42 mg/24 hours; p=0.01). CONCLUSIONS: Everolimus regimen compared with EC-MPS regimen is associated with lower incidence of DGF, slightly better 1-year graft survival rate, a significantly higher GFR and lower systolic blood pressure.