The role of protocol biopsies after pediatric kidney transplantation.

Data on protocol biopsies (PBs) after pediatric kidney transplantation are rare.We evaluated 6-month post-transplantation renal function in 86 children after PB as observational study. Patients were divided into 3 groups:Glomerular filtration rate (GFR) and delta GFR were determined.PBs 6 months post-kidney transplantation did not influence the clinical course in stable pediatric patients and are therefore of questionable value. Decreased kidney function may however be stabilized by therapeutic intervention according to results of PB.

Graft outcomes following diagnosis of post-transplant lymphoproliferative disease in pediatric kidney recipients: a retrospective study.

Data related to graft outcomes following post-transplant lymphoproliferative disease (PTLD) in pediatric kidney transplantation are scarce. Data were analyzed retrospectively from 12 children (eight boys) for 3 years after diagnosis of PTLD, with a loss of follow-up after 2 years in two of 12. In all cases, intensity of immunosuppressive therapy was reduced, which switched from calcineurin inhibitor to a mammalian target of rapamycin (mTOR) inhibitor in ten cases. Nine children were treated with six doses of rituximab according to the PED-PTLD-2005 protocol, with additional treatment in one child as per protocol. One patient received EuroNet-PHL C1. In four patients, donor-specific antibodies were detected after PTLD diagnosis at 3, 4, 5 and 7 years, respectively. One patient developed chronic antibody-mediated rejection (cAMR) 12 years after diagnosis, losing the graft 1 year later. Three patients with recurrence of the original disease also lost their grafts, one at the time of diagnosis of PTLD, and two after 4 years. Range-based analysis of variance showed that there was no decrease in estimated GFR at 1, 2, or 3 years after diagnosis of PTLD (P = 0.978). In conclusion, treatment of PTLD with reduced immunosuppression is safe and efficient. This may be due to B-cell-depleting therapy of PTLD with rituximab.

Switching from immediate- to extended-release cysteamine in nephropathic cystinosis patients: a retrospective real-life single-center study.

BACKGROUND: Nephropathic cystinosis is a rare lysosomal storage disease which is characterized by the accumulation of free cystine in lysosomes and subsequent intracellular crystal formation of cystine throughout the body. If not treated with cysteamine, a cystine-depleting agent, end-stage renal disease will develop early, followed by multiple organ failure as the disease progresses. The established cysteamine formulation requires a strict dosing regimen at 6-h intervals. An extended release (ER) twice-daily formulation has recently been developed. The aim of our study was to evaluate the implementation and outcomes of this option in routine care. METHODS: All pediatric cystinosis patients' records in Hannover Medical School were screened, and data on cysteamine therapy, tolerability, dosing, estimated glomerular filtration rates (eGFR), white blood cell cystine levels, and proton pump inhibitor (PPI) use were extracted for the period January 2014 to January 2016. RESULTS: The median age of the 12 patients enrolled in the study was 12.5 (range 1-18) years. At the end of the study period ten of these patients received ER-cysteamine. There were no additional side effects. Halitosis/bad breath was often subjectively judged as improved or eliminated, and PPI use could be stopped in one of three patients. The main reasons for switching to the ER formulation were difficult night-time administration and uncontrolled disease. Mean eGFR values remained stable with a median of 67 ml/min/1.73 m2 before and after the transition. White blood cell (WBC) cystine values remained low after the switch (1 nmol/mg protein before and after transition; p = 0.64). CONCLUSIONS: In this single-center cohort, the switch from IR- to ER-cysteamine was safe and effective over the short term and provided advantages in terms of frequency of administration and less halitosis/bad breath. The long-term benefit of this option needs to be evaluated in future studies.

Correlations with six-month protocol biopsy findings in pediatric transplant recipients on low- and regular-dose CNI regimens.

Protocol biopsies (PB) are seldom performed after pediatric kidney transplantation (KTx), and factors influencing PB results have not previously been investigated. We performed PB in 79 children six months after KTx and evaluated the results using Banff 2007 criteria. Complications such as bleeding or infections were not detected. The influence of different variables on PB results was evaluated by covariance analysis. Children treated with a low-dose calcineurin inhibitor (CNI) together with an mTOR inhibitor exhibited decreased subclinical rejection (0% vs. 19%, p = 0.001) and decreased interstitial fibrosis and tubular atrophy (IF/TA) (15% vs. 42%, p = 0.013) compared with patients treated with a conventional regimen consisting of normal-dose CNI and mycophenolate mofetil. Children with IF/TA had a lower GFR four wk after Tx (83 ± 22 vs. 62 ± 20 mL/min/1.73 m(2) , p = 0.001). Cold ischemia time, living-related donors, pre-emptive KTx, and donor age did not influence PB results. Treatment with low-dose CNI and mTOR inhibitor and high GFR directly after Tx are the main factors associated with less inflammation and fibrosis in PB and might therefore lead to better long-term graft function.

Generalized atherosclerosis sparing the transplanted kidney in Schimke disease.

Schimke-immuno-osseous dysplasia (SIOD) is a multisystem disorder caused by a mutation of the chromatin remodeling protein. The main clinical findings are spondyloepiphyseal dysplasia with disproportional growth deficiency, nephrotic syndrome with focal and segmental glomerulosclerosis, and defective cellular immunity. Transitory ischemic attacks due to vaso-occlusive processes are still an untreatable and life-limiting complication in patients with SIOD. The underlying pathophysiology of vaso-occlusive processes in SIOD is unclear. We report the clinical and pathological findings of the eldest published patient with the severe form of SIOD, who died at the age of 23 years due to pulmonary hypertension with subsequent right heart failure. The autopsy revealed a severe generalized atherosclerosis including the brain, heart, and pulmonary arteries. However, the kidney that was transplanted at the age of 5 years showed a good graft function without glomerular sclerosis and with only minimal nephrosclerosis on histology. Thus, the absence of severe vaso-occlusive processes in the transplanted organ and in the severely atherosclerotic host may indicate that the vaso-occlusive processes in SIOD are not caused by post-transplant cardiovascular morbidity such as arterial hypertension and hyperlipidemia. Instead, vascular factors of the host such as endothelial dysfunction may explain the pathophysiology of atherosclerosis in SIOD.