Vitamin D-Dependent Rickets Type 1A in Two Siblings with a Hypomorphic CYP27B1 Variant Frequent in the African Population.

Vitamin D-dependent type 1A rickets (VDDR-1A) is a rare autosomal recessive disease due to the inability to convert 25-hydroxyvitamin D [25(OH)D] to the active form 1.25-dihydroxyvitamin D [1.25(OH) 2 D] by the enzyme 25(OH)D-1α-hydroxylase leading to low or low-normal serum levels of [1.25(OH) 2 D]. We report two sisters with rickets in whom the diagnosis of VDDR-1A was a challenge. They had normal 1.25(OH)2D levels, which are unusual with this condition but may be explained by the identified genotype. Both have compound heterozygous for two, most likely, hypomorphic CYP27B1 alleles: the novel p.(Arg117Gly) variant, and p.(Ala129Thr), which are present in 0.43% of the African population. This report illustrates the variability of clinical, laboratory, and radiological presentation between two sisters with the same genotype, during phases of faster or slower growth. Genetic testing was crucial for establishing the diagnosis that optimized the management and genetic counseling.

IgA vasculitis (Henoch-Schönlein purpura) nephritis and psoriasis in a child: is there a relationship? / Vasculite por IgA (púrpura de Henoch-Schönlein), nefrite e psoríase em uma criança: existe relação?

Abstract Background Psoriasis is a chronic immune-mediated disorder that primarily affects the skin in both adults and children but can also have systemic involvement, particularly with arthritis and kidney injury. IgA nephropathy is the most frequent kidney disorder associated with psoriasis. Approximately one third of all cases of psoriasis begin in childhood, but association between psoriasis and renal disorders has scarcely been reported in pediatric patients. Henoch-Schönlein purpura (HSP) is a systemic vasculitis characterized by IgA deposits in the vessel walls of affected organs and in the mesangium of the kidney. HSP nephritis histopathology is identical to IgA nephropathy. Case report A 6-year-old boy with recent onset of psoriasis developed HSP with kidney involvement, clinically manifested by nephrotic-range proteinuria and hematuria. Kidney biopsy revealed fibrocellular glomerular crescents and mesangial IgA deposits compatible with IgA nephropathy. Treatment with systemic corticosteroids led to the control of hematuria, but as nephrotic-range proteinuria persisted, cyclophosphamide was added, leading to a gradual decrease in proteinuria. Conclusions We propose an underlying common mechanism in the pathogenesis of both HSP and psoriasis, involving a dysregulation of the IgA-mediated immune response, which could predispose to both entities as well as to kidney damage and IgA nephropathy in these patients.

Resumo Histórico A psoríase é uma doença crônica imunomediada que afeta principalmente a pele tanto em adultos quanto em crianças, mas também pode ter envolvimento sistêmico, particularmente com artrite e lesão renal. A nefropatia por IgA é o distúrbio renal mais frequentemente associado à psoríase. Aproximadamente um terço de todos os casos de psoríase começam na infância, mas a associação entre psoríase e distúrbios renais tem sido pouco relatada em pacientes pediátricos. A Púrpura de Henoch-Schönlein (PHS) é uma vasculite sistêmica caracterizada por depósitos de IgA nas paredes dos vasos de órgãos afetados e no mesângio do rim. A histopatologia da nefrite da PHS é idêntica à da nefropatia por IgA. Relato de caso Um menino de 6 anos de idade com início recente de psoríase desenvolveu PHS com envolvimento renal, clinicamente manifestado por proteinúria nefrótica e hematúria. A biópsia renal revelou crescentes fibrocelulares glomerulares e depósitos mesangiais de IgA compatíveis com a nefropatia por IgA. O tratamento com corticosteróides sistêmicos levou ao controle da hematúria, mas como a proteinúria nefrótica persistiu, a ciclofosfamida foi adicionada, levando a uma diminuição gradual da proteinúria. Conclusões Propomos um mecanismo comum subjacente na patogênese tanto da PHS quanto da psoríase, envolvendo uma desregulação da resposta imune mediada por IgA, que poderia predispor a ambas as entidades, bem como a danos renais e nefropatia por IgA nesses pacientes.

Current Practices on Diagnosis, Prevention and Treatment of Post-Transplant Lymphoproliferative Disorder in Pediatric Patients after Solid Organ Transplantation: Results of ERN TransplantChild Healthcare Working Group Survey.

(1) Background: Post-transplant lymphoproliferative disease (PTLD) is a significant complication of solid organ transplantation (SOT). However, there is lack of consensus in PTLD management. Our aim was to establish a present benchmark for comparison between international centers and between various organ transplant systems and modalities; (2) Methods: A cross-sectional questionnaire of relevant PTLD practices in pediatric transplantation was sent to multidisciplinary teams from 17 European center members of ERN TransplantChild to evaluate the centers' approach strategies for diagnosis and treatment and how current practices impact a cross-sectional series of PTLD cases; (3) Results: A total of 34 SOT programs from 13 European centers participated. The decision to start preemptive treatment and its guidance was based on both EBV viremia monitoring plus additional laboratory methods and clinical assessment (61%). Among treatment modalities the most common initial practice at diagnosis was to reduce the immunosuppression (61%). A total of 126 PTLD cases were reported during the period 2012-2016. According to their histopathological classification, monomorphic lesions were the most frequent (46%). Graft rejection after PTLD remission was 33%. Of the total cases diagnosed with PTLD, 88% survived; (4) Conclusions: There is still no consensus on prevention and treatment of PTLD, which implies the need to generate evidence. This might successively allow the development of clinical guidelines.

Nutcracker Syndrome: A Single-Center Experience.

Nutcracker syndrome, whose prevalence and natural history are still poorly known, is a clinical syndrome caused by left renal vein compression between the superior mesenteric artery and the aorta. Long-term results and treatment outcomes are not well known. Our group aimed to characterize 7 patients diagnosed with nutcracker syndrome in childhood and to describe their clinical manifestations, diagnostic approaches, and mostly their clinical evolution, rate of complications, and treatment outcomes.

IgA vasculitis (Henoch-Schönlein purpura) nephritis and psoriasis in a child: is there a relationship?

BACKGROUND: Psoriasis is a chronic immune-mediated disorder that primarily affects the skin in both adults and children but can also have systemic involvement, particularly with arthritis and kidney injury. IgA nephropathy is the most frequent kidney disorder associated with psoriasis. Approximately one third of all cases of psoriasis begin in childhood, but association between psoriasis and renal disorders has scarcely been reported in pediatric patients. Henoch-Schönlein purpura (HSP) is a systemic vasculitis characterized by IgA deposits in the vessel walls of affected organs and in the mesangium of the kidney. HSP nephritis histopathology is identical to IgA nephropathy. CASE REPORT: A 6-year-old boy with recent onset of psoriasis developed HSP with kidney involvement, clinically manifested by nephrotic-range proteinuria and hematuria. Kidney biopsy revealed fibrocellular glomerular crescents and mesangial IgA deposits compatible with IgA nephropathy. Treatment with systemic corticosteroids led to the control of hematuria, but as nephrotic-range proteinuria persisted, cyclophosphamide was added, leading to a gradual decrease in proteinuria. CONCLUSIONS: We propose an underlying common mechanism in the pathogenesis of both HSP and psoriasis, involving a dysregulation of the IgA-mediated immune response, which could predispose to both entities as well as to kidney damage and IgA nephropathy in these patients.

Results in the ESPN/ERA-EDTA Registry suggest disparities in access to kidney transplantation but little variation in graft survival of children across Europe.

One of the main objectives of the European health policy framework is to ensure equitable access to high-quality health services across Europe. Here we examined country-specific kidney transplantation and graft failure rates in children and explore their country- and patient-level determinants. Patients under 20 years of age initiating kidney replacement therapy from January 2007 through December 2015 in 37 European countries participating in the ESPN/ERA-EDTA Registry were included in the analyses. Countries were categorized as low-, middle-, and high-income based on gross domestic product. At five years of follow-up, 4326 of 6909 children on kidney replacement therapy received their first kidney transplant. Overall median time from kidney replacement therapy start to first kidney transplantation was 1.4 (inter quartile range 0.3-4.3) years. The five-year kidney transplantation probability was 48.8% (95% confidence interval: 45.9-51.7%) in low-income, 76.3% (72.8-79.5%) in middle-income and 92.3% (91.0-93.4%) in high-income countries and was strongly associated with macro-economic factors. Gross domestic product alone explained 67% of the international variation in transplantation rates. Compared with high-income countries, kidney transplantation was 76% less likely to be performed in low-income and 58% less likely in middle-income countries. Overall five-year graft survival in Europe was 88% and showed little variation across countries. Thus, despite large disparities transplantation access across Europe, graft failure rates were relatively similar. Hence, graft survival in low-risk transplant recipients from lower-income countries seems as good as graft survival among all (low-, medium-, and high-risk) graft recipients from high-income countries.

[Distal Renal Tubular Acidosis: Clinical Variability in the Same Family]. / Acidose Tubular Renal Distal: Expressão Clínica Variável na Mesma Família.

Primary distal renal tubular acidosis is a genetic disorder characterized by the inability in acidification of urine. Symptoms are usually non-specific and highly variable. We described six cases in a family with four generations affected. The first case was diagnosed in a 3-year-old child presenting with hematuria and urolithiasis. Later, his sister, sons and two nephews were studied. Although asymptomatic, they all had nephrocalcinosis and hyperchloremic metabolic acidosis with normal anionic gap, except one case with normal arterial blood gas test but with nephrocalcinosis and inability of urinary acidification. At follow-up, they all maintained nephrocalcinosis, the index case had acute renal damage and developed hypertension, but none developed chronic renal disease. The diagnosis of autosomal dominant distal renal tubular acidosis is generally made later and patients tend to present with milder disease. But the condition may manifest early and have a variable phenotypic severity spectrum. Carrying out screening through assessment of family history enables an earlier diagnosis while also allowing treatment to start sooner.

A acidose tubular renal distal primária deve-se a um defeito genético caracterizado pela incapacidade de acidificar a urina. A sintomatologia é inespecífica e muito variável. Descrevem-se seis casos de acidose tubular renal distal numa família em que a doença afetou quatro gerações. O primeiro caso foi diagnosticado aos três anos por hematúria e urolitíase. Posteriormente foram estudados a irmã, os dois filhos e dois sobrinhos do caso índex. Apesar de assintomáticos, todos apresentavam nefrocalcinose e acidose metabólica hiperclorémica, à exceção de um caso com gasimetria normal mas com nefrocalcinose e incapacidade de acidificação urinária. Na evolução todos mantiveram nefrocalcinose, o caso índex desenvolveu hipertensão arterial mas nenhum evoluiu para insuficiência renal crónica. O diagnóstico da acidose tubular renal distal autossómica dominante é geralmente mais tardio e com sintomatologia mais ligeira. A doença pode contudo manifestar-se precocemente e com espectro de gravidade variável. O rastreio pela história familiar permite antecipar o diagnóstico e iniciar tratamento mais precocemente.

Pediatric Kidney Transplantation: Experience of a Center Over 4 Decades.

INTRODUCTION: Chronic kidney disease in the pediatric population is associated with numerous comorbidities and an increased risk of mortality. Kidney transplantation (KT) is considered to be the option of choice in children with end-stage renal disease. AIM: To characterize a single center experience in pediatric KT in the last 35 years. METHODS: A retrospective analysis of epidemiologic and clinical data from KT pediatric patients from January 1981 to December 2016. For outcome analysis, cases were divided into decades (1981-89; 1990-99; 2000-09; 2010-16). RESULTS: One hundred and 4 children (KT mean age 13.7 ± 3.32 years; 57.7% male) underwent 111 renal transplants (13% with living donors). Congenital anomalies of the kidney and urinary tract (36.5%) and glomerular disease (29%) were the major causes of renal disease. Peritoneal dialysis was the predominant initial therapeutic modality in 69 children (62.2%). Mean dialysis time was 19.2 months, 9 patients (8.1%) having had preemptive KT. Median follow-up was 181 months. Uncensored graft survivals rates at 5, 10, 15, and 20 years were 79.7%, 74.3%, 59.5%, and 52.8%, respectively. Graft survival improved significantly over the decades (P = .03). Higher estimated glomerular filtration rate measured at 1 year, induction immunosuppressive therapy use (thymoglobulin/basiliximab), and lower incidence of acute rejection rates were associated with superior graft survival (P < .05). CONCLUSIONS: Uronephropathies were the most frequent cause of renal failure and peritoneal dialysis, which was the main renal replacement therapy according to the literature. Graft survival improved significantly over the study period; we hypothesize that this was related to surgical advances and the use of more effective immunosuppressive drugs.