Unexpected Gaucher disease in a case of steroid-resistant nephrotic syndrome.

Gaucher disease (GD), the most common lysosomal storage disorder worldwide, should be considered in children presenting with unexplained hepatosplenomegaly and cytopenia. Kidney involvement is rare, and nephrotic syndrome constitutes an uncommon complication. We describe a 15-month-old female, the first child of consanguineous parents, who initially presented with infantile nephrotic syndrome. Kidney biopsy revealed focal segmental glomerulosclerosis (FSGS). The patient had the first corticosteroid treatment without any improvement. Mycophenolate mofetil was then added, resulting in partial remission. The patient subsequently developed pancytopenia, progressive stridor, hepatosplenomegaly, and recurrent seizures. Molecular genetic testing confirmed GD. Enzyme replacement therapy (ERT) improved cytopenia, seizure control, and organomegaly, as well as uremic manifestations; however, progression to kidney failure was not reversed.