Crescentic glomerulonephritis associated with nail-patella syndrome in a 13-year-old girl

Abstract

Nail-patella syndrome (NPS), also known as hereditary osteoonychodysplasia, is a rare autosomal dominant pleiotropic disorder, defined by the association of nail dysplasia, skeletal abnormalities and renal lesions.(1) Skeletal features include absent or hypoplastic patella, patella dislocation, elbow abnormalities (like knee abnormalities), and iliac horns on X-ray. Renal involvement is considered the most serious component and the cause of lethality of this syndrome. Renal involvement may lead to renal failure.(2) The main pathology involves a defect in the glomerular basement membrane (GBM), which has irregular thickening containing electron-lucent areas. The first sign of renal involvement is usually proteinuria, with or without haematuria.(3) Previous studies have estimated that renal involvement occurred in 12-55% of patients with NPS,(4) and renal failure in 5-14% of NPS patients.(5)