Schimke immuno-osseous dysplasia (SIOD) is a rare multisystem disorder with early mortality and steroid-resistant nephrotic syndrome (SRNS) progressing to end-stage kidney disease. We hypothesized that next-generation gene panel sequencing may unsurface oligosymptomatic cases of SIOD with potentially milder disease courses. We analyzed the renal and extrarenal phenotypic spectrum and genotype-phenotype associations in 34 patients from 28 families, the largest SMARCAL1-associated nephropathy cohort to date. In 11 patients the diagnosis was made unsuspectedly through SRNS gene panel testing. Renal disease first manifested at median age 4.5 yrs, with focal segmental glmerulosclerosis or minimal change nephropathy on biopsy and rapid progression to end-stage kidney disease (ESKD) at median age 8.7 yrs. Whereas patients diagnosed by phenotype more frequently developed severe extrarenal complications (cerebral ischemic events, septicemia) and were more likely to die before age 10 years than patients identified by SRNS-gene panel screening (88 vs. 40%), the subgroups did not differ with respect to age at proteinuria onset and progression to ESKD. Also, 10 of 11 children diagnosed unsuspectedly by Next Generation Sequencing were small at diagnosis and all showed progressive growth failure. Severe phenotypes were usually associated with biallelic truncating mutations and milder phenotypes with biallelic missense mutations. However, no genotype-phenotype correlation was observed for the renal disease course. In conclusion, while short stature is a reliable clue to SIOD in children with SRNS, other systemic features are highly variable. Our findings support routine SMARCAL1 testing also in non-syndromic SRNS.

• MeSH
• arterioskleróza diagnóza   genetika   patologie   MeSH
• dítě MeSH
• DNA-helikasy genetika   MeSH
• dospělí MeSH
• fenotyp MeSH
• genetické testování MeSH
• genotyp MeSH
• kohortové studie MeSH
• kojenec MeSH
• ledviny patologie   MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mutace MeSH
• nefrotický syndrom diagnóza   genetika   patologie   MeSH
• osteochondrodysplazie diagnóza   genetika   patologie   MeSH
• plicní embolie diagnóza   genetika   patologie   MeSH
• předškolní dítě MeSH
• primární imunodeficience MeSH
• syndromy imunologické nedostatečnosti diagnóza   genetika   patologie   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• kojenec MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• předškolní dítě MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• DNA-helikasy MeSH
• SMARCAL1 protein, human MeSH Prohlížeč

WT1 mutations cause a wide spectrum of renal and extrarenal manifestations. Here we evaluated disease prevalence, phenotype spectrum, and genotype-phenotype correlations of 61 patients with WT1-related steroid-resistant nephrotic syndrome relative to 700 WT1-negative patients, all with steroid-resistant nephrotic syndrome. WT1 patients more frequently presented with chronic kidney disease and hypertension at diagnosis and exhibited more rapid disease progression. Focal segmental glomerulosclerosis was equally prevalent in both cohorts, but diffuse mesangial sclerosis was largely specific for WT1 disease and was present in 34% of cases. Sex reversal and/or urogenital abnormalities (52%), Wilms tumor (38%), and gonadoblastoma (5%) were almost exclusive to WT1 disease. Missense substitutions affecting DNA-binding residues were associated with diffuse mesangial sclerosis (74%), early steroid-resistant nephrotic syndrome onset, and rapid progression to ESRD. Truncating mutations conferred the highest Wilms tumor risk (78%) but typically late-onset steroid-resistant nephrotic syndrome. Intronic (KTS) mutations were most likely to present as isolated steroid-resistant nephrotic syndrome (37%) with a median onset at an age of 4.5 years, focal segmental glomerulosclerosis on biopsy, and slow progression (median ESRD age 13.6 years). Thus, there is a wide range of expressivity, solid genotype-phenotype associations, and a high risk and significance of extrarenal complications in WT1-associated nephropathy. We suggest that all children with steroid-resistant nephrotic syndrome undergo WT1 gene screening.

• MeSH
• časové faktory MeSH
• chronická renální insuficience diagnóza   epidemiologie   genetika   terapie   MeSH
• dítě MeSH
• fenotyp MeSH
• fokálně segmentální glomeruloskleróza diagnóza   epidemiologie   genetika   terapie   MeSH
• genetická predispozice k nemoci MeSH
• genetické asociační studie MeSH
• genetické testování metody   MeSH
• incidence MeSH
• kojenec MeSH
• lidé MeSH
• mutace * MeSH
• mutační analýza DNA MeSH
• nefrotický syndrom vrozené   diagnóza   epidemiologie   genetika   terapie   MeSH
• předškolní dítě MeSH
• prevalence MeSH
• prognóza MeSH
• progrese nemoci MeSH
• proteiny WT1 genetika   MeSH
• registrace MeSH
• rizikové faktory MeSH
• věk při počátku nemoci MeSH
• Check Tag
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH
• Názvy látek
• proteiny WT1 MeSH
• WT1 protein, human MeSH Prohlížeč