Clinical and Genetic Profile of Indian Children with Primary Hyperoxaluria.

Primary hyperoxaluria (PH) has heterogeneous renal manifestations in infants and children. This often leads to delay in diagnosis. In the past 3 years, genetic samples were sent for seven children with a clinical diagnosis of PH. Their medical records were reviewed for clinical presentation and outcomes. Of the seven children, three were males. The median age of presentation was 4.9 years with the youngest presenting at 3 months of age. Nephrolithiasis, the most common presentation was associated with renal dysfunction in two children. Two children with no significant history presented in end-stage renal disease (ESRD). The sibling of one of the children in ESRD, with a history of consanguinity in parents, was screened for asymptomatic nephrolithiasis. Bilateral multiple renal calculi were found in majority of children followed by echogenic kidneys on ultrasound examination. Genetic analysis suggested PH Type 1 in five children and type 2 in two children. The mutations detected in our cohort were different from the previously reported common mutations. There was no obvious genotype-phenotype correlation noticed. Three children in ESRD are on maintenance dialysis. Nephrolithiasis being a common presentation of PH needs prompt evaluation. Mutations are generally population specific, and whole gene sequence analysis is critical in diagnosis.