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.

Disparities in treatment and outcome of kidney replacement therapy in children with comorbidities: an ESPN/ERA Registry study.

Background: Data on comorbidities in children on kidney replacement therapy (KRT) are scarce. Considering their high relevance for prognosis and treatment, this study aims to analyse the prevalence and implications of comorbidities in European children on KRT. Methods: We included data from patients <20 years of age when commencing KRT from 2007 to 2017 from 22 European countries within the European Society of Paediatric Nephrology/European Renal Association Registry. Differences between patients with and without comorbidities in access to kidney transplantation (KT) and patient and graft survival were estimated using Cox regression. Results: Comorbidities were present in 33% of the 4127 children commencing KRT and the prevalence has steadily increased by 5% annually since 2007. Comorbidities were most frequent in high-income countries (43% versus 24% in low-income countries and 33% in middle-income countries). Patients with comorbidities had a lower access to transplantation {adjusted hazard ratio [aHR] 0.67 [95% confidence interval (CI) 0.61-0.74]} and a higher risk of death [aHR 1.79 (95% CI 1.38-2.32)]. The increased mortality was only seen in dialysis patients [aHR 1.60 (95% CI 1.21-2.13)], and not after KT. For both outcomes, the impact of comorbidities was stronger in low-income countries. Graft survival was not affected by the presence of comorbidities [aHR for 5-year graft failure 1.18 (95% CI 0.84-1.65)]. Conclusions: Comorbidities have become more frequent in children on KRT and reduce their access to transplantation and survival, especially when remaining on dialysis. KT should be considered as an option in all paediatric KRT patients and efforts should be made to identify modifiable barriers to KT for children with comorbidities.

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.

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.

[Diagnostic and Therapeutic Challenges in Atypical Hemolytic Uremic Syndrome: A Case Report]. / Desafios Diagnósticos e Terapêuticos na Síndrome Hemolítica Urémica Atípica: A Propósito de Um Caso Clínico.

The atypical hemolytic uremic syndrome comprises a thrombotic microangiopathy resulting from the complement alternate pathway hyperactivation. Its severity requires early diagnosis and treatment. The differential diagnosis includes typical hemolytic uremic syndrome (associated with Shiga toxin) and thrombotic thrombocytopenic purpura (associated with deficient activity of ADAMTS13). The only specific treatment currently available for atypical hemolytic uremic syndrome is eculizumab. We describe the case of a child with atypical hemolytic uremic syndrome diagnosed in the context of bloody diarrhea, complicated by neurological involvement that posed several diagnostic and therapeutic challenges.

A síndrome hemolítica urémica atípica constitui uma microangiopatia trombótica resultante da hiperativação da via alterna do complemento. A sua gravidade exige diagnóstico e terapêutica precoces. O diagnóstico diferencial inclui a síndrome hemolítica urémica típica (associada à toxina Shiga) e a púrpura trombótica trombocitopénica (associada a deficiência na atividade da ADAMTS13). A terapêutica específica da síndrome hemolítica urémica atípica, atualmente disponível, é o eculizumab. Descrevemos um caso clínico de uma criança com síndrome hemolítica urémica atípica diagnosticada em contexto de diarreia sanguinolenta, complicada de envolvimento neurológico e que colocou vários desafios no diagnóstico e decisões terapêuticas.

[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.

Cerebral Venous Sinus Thrombosis in a Child with Idiopathic Nephrotic Syndrome: a case report / Trombose Venosa Cerebral na apresentação de Síndrome Nefrótica Pediátrica: caso clínico

ABSTRACT Complications are rare in pediatric cases of idiopathic nephrotic syndrome (NS). Thromboembolism ranks among the most uncommon and difficult complications to diagnose, particularly in the first episode of NS, since clinical signs might be unspecific. This report describes the case of a 5-year-old girl with NS for the first time presenting with severe hypoalbuminemia (< 2g/dL). The patient responded poorly to therapy with corticosteroids. On day 8 of hospitalization she started having headaches and vomiting; she did not present hemodynamic alterations, fever or exanthems, and her neurological parameters were normal. The patient was suspected for intracranial hypertension, and computed tomography scans revealed she had cerebral venous sinus thrombosis (CVST). She was started on anticoagulants and showed clinical signs of improvement. The patient had no evident prothrombotic risk factors. She had three other episodes since she was diagnosed, one in which her plasma antithrombin level was low. Although antithrombin levels were normal in her first episode, she was tested after the resolution of proteinuria. The low levels of antithrombin seen in the first recurrence might have mirrored the initial drop in plasma antithrombin levels, an idea supported by the severe hypoalbuminemia she had when diagnosed. This severe manifestation of acquired thrombophilia might be in the origin of CVST. This report presents a rare case of thromboembolic complication in a pediatric patient with NS. The patient progressed well since she was started on anticoagulants. Although she did not present any evident risk factors at first, the development of her case indicated that severe acquired thrombophilia might have worked as the pathophysiological mechanism leading to CVST.

RESUMO A Síndrome Nefrótica (SN) idiopática em crianças pode, raramente, complicar-se. O tromboembolismo é uma das complicações mais raras, principalmente no primeiro episódio, e de diagnóstico mais difícil, uma vez que a clínica pode ser inespecífica. Descrevemos o caso de uma criança de 5 anos com episódio inaugural de SN, destacando-se hipoalbuminemia inicial grave (< 2g/dL). Apresentou fraca resposta inicial à corticoterapia e, após 8 dias de internamento, iniciou quadro de cefaleias e vômitos, sem alterações hemodinâmicas, sem febre, sem exantema e com exame neurológico normal. Perante a suspeita de hipertensão intracraniana, foi realizada TC-CE, que mostrou trombose venosa cerebral (TVC). Foi então iniciada terapêutica anticoagulante com posterior boa evolução clínica. Trata-se de uma criança sem fatores de risco pró-trombóticos evidentes. Desde o diagnóstico, teve 3 recaídas, uma das quais com níveis baixos de antitrombina, que no episódio inaugural eram normais, apesar de avaliados já numa fase não proteinúrica. Suspeita-se, assim, que esse déficit plasmático em antitrombina na recaída poderá mimetizar a queda plasmática inicial, hipótese também apoiada pela hipoalbuminemia grave ao diagnóstico. Esta trombofília grave adquirida poderá ter sido mecanismo etiológico para a trombose venosa cerebral. O interesse deste caso prende-se com a raridade de complicações tromboembólicas na SN Pediátrica, ainda mais raras no episódio inaugural. Nesse caso, a boa evolução foi possível após a associação da terapêutica anticoagulante. Embora sem fatores de risco iniciais evidentes, a evolução do caso permitiu a suspeita de uma trombofília adquirida grave como mecanismo fisiopatológico do tromboembolismo cerebral.

Cerebral Venous Sinus Thrombosis in a Child with Idiopathic Nephrotic Syndrome: a case report.

Complications are rare in pediatric cases of idiopathic nephrotic syndrome (NS). Thromboembolism ranks among the most uncommon and difficult complications to diagnose, particularly in the first episode of NS, since clinical signs might be unspecific. This report describes the case of a 5-year-old girl with NS for the first time presenting with severe hypoalbuminemia (< 2g/dL). The patient responded poorly to therapy with corticosteroids. On day 8 of hospitalization she started having headaches and vomiting; she did not present hemodynamic alterations, fever or exanthems, and her neurological parameters were normal. The patient was suspected for intracranial hypertension, and computed tomography scans revealed she had cerebral venous sinus thrombosis (CVST). She was started on anticoagulants and showed clinical signs of improvement. The patient had no evident prothrombotic risk factors. She had three other episodes since she was diagnosed, one in which her plasma antithrombin level was low. Although antithrombin levels were normal in her first episode, she was tested after the resolution of proteinuria. The low levels of antithrombin seen in the first recurrence might have mirrored the initial drop in plasma antithrombin levels, an idea supported by the severe hypoalbuminemia she had when diagnosed. This severe manifestation of acquired thrombophilia might be in the origin of CVST. This report presents a rare case of thromboembolic complication in a pediatric patient with NS. The patient progressed well since she was started on anticoagulants. Although she did not present any evident risk factors at first, the development of her case indicated that severe acquired thrombophilia might have worked as the pathophysiological mechanism leading to CVST.

Bilateral renal cell carcinoma in a paediatric patient with tuberous sclerosis complex.

Tuberous sclerosis complex (TSC) is a genetic neurocutaneous disorder characterised by seizures, mental retardation and hamartoma formation in multiple organs, mainly in the brain, skin, kidney, liver, lung and heart. Renal manifestations occur in about 60-80% of all patients with TSC and their rate increases with age. We report the case of a 17-year-old boy with tuberous sclerosis who presented with abdominal pain associated with kidney failure. Investigation revealed bilateral renal lesions, suggesting angiomyolipomas. On further work-up, malignancy was suspected and the patient underwent bilateral partial nephrectomy with histological diagnosis of bilateral renal cell carcinoma. This is a rare complication of TSC, particularly in a paediatric setting. Adequate surveillance of kidney disorders in patients with TSC is warranted, to guarantee an early diagnosis and treatment.

[Asymptomatic cardiac tumor in a child: an incidental diagnosis]. / Tumor cardíaco em criança assintomática: um diagnóstico acidental.

Cardiac tumors in the pediatric population are rare, their incidence range between 0.001% and 0.003%. They are mostly benign, rhabdomyomas the most common type, followed by fibromas. The clinical features are being usually nonspecific and depend on the size and location of the tumor within the heart. We report the case of a previously healthy four-year-old boy referred for flu-like symptoms. A respiratory infection was suspected and a chest X-ray showed an increased cardiothoracic index. An echocardiogram revealed a single large heterogeneous mass in the left ventricle emerging from the lateral wall. Despite its size, the mass did not obstruct the left ventricular outflow tract or affect mitral valve function. Cardiac magnetic resonance imaging showed a large mass whose imaging features were suggestive of a fibroma. He became symptomatic during follow-up and was referred for surgical excision of the mass. Histological study confirmed a fibroma. At present the patient remains asymptomatic.

Severe axillary lymphadenitis after BCG vaccination: alert for primary immunodeficiencies.

The bacilli Calmette-Guérin (BCG) vaccine is administered to all newborns in countries where tuberculosis is endemic. Immunocompromised hosts, namely patients with human immunodeficiency virus infection or primary immunodeficiencies, are especially prone to serious complications from this vaccine. We report three cases of BCG disease in children with primary immunodeficiencies: one with a partial recessive interferon-γ receptor 1 deficiency, who developed BCG dissemination; and two relatives with ZAP70 deficiency, a severe combined immunodeficiency, both of whom presented with regional and distant BCG disease. All had severe axillary lymphadenitis. These clinical cases underline the importance of considering the diagnosis of immunodeficiency in a child with severe axillary lymphadenitis after BCG vaccination and of disseminated BCG disease in an immunodeficient child in the appropriate clinical setting. Moreover, BCG vaccination should be delayed in every newborn with a family history of primary immunodeficiency until the condition has been ruled out.