A case of concurrent Alport syndrome and Nail-patella syndrome posing diagnostic challenge without genetic testing

Hereditary glomerular basement membrane disease is a group of conditions caused by genetic mutations in the development and maintenance of the glomerular basement membrane. Alport syndrome is a classic example caused by variants in the genes COL4A3, COL4A4, or COL4A5. Less common example includes nail-patella syndrome (LMX1B-associated nephropathy), which is caused by variants in the LMX1B gene. The manifestations of LMX1B-associated nephropathy and Alport syndrome can overlap because they share abnormalities in type IV collagen, and this can sometimes cause diagnostic challenges. We describe a case of focal segmental glomerulosclerosis with the genetic test revealing concurrent variants of both Alport syndrome and nail-patella syndrome after noting features of nail-patella syndrome on clinical examination, although the kidney biopsy showed features compatible with Alport syndrome. Our case highlighted the importance of astute clinical examination backed up by genetic testing, which aids in diagnosis and subsequent management.