Alport syndrome complicated with IgA nephropathy: a case report

Alport syndrome (AS) and immunoglobulin A (IgA) nephropathy (IgAN) are distinct renal disorders characterized by hematuria and proteinuria. AS is a rare hereditary condition caused by mutations in genes encoding collagen IV α-chains, leading to abnormalities of the glomerular basement membrane. However, IgAN is an autoimmune disorder characterized by glycosylation defects in IgA1, leading to dysfunction of glomerular filtration. Approximately 15% of IgAN cases exhibit familial clustering, and some may harbor gene mutations associated with AS. A 29-year-old woman with no family history of nephropathy presented with hematuria and proteinuria. The renal biopsy revealed foamy interstitial cells. Electron microscopy indicated a torn basement membrane, indicating a diagnosis of concurrent AS and mild mesangial proliferative IgAN. Genetic testing confirmed a mutation consistent with X-linked AS. Moreover, she exhibited high-frequency hearing loss in her left ear. Initial treatment included angiotensin receptor blockers and sodium-glucose co-transporter-2 inhibitors. Corticosteroids and mycophenolate mofetil were introduced prior to genetic testing, although their efficacy was limited. Despite the co-occurrence of multiple nephropathies, this case suggests the usefulness of renal biopsy and genetic testing for accurately diagnosing kidney disease, which can help initiate appropriate treatments early. The treatment regimen did not provide significant benefits in this patient with concurrent AS and IgAN. This emphasizes the need for targeted diagnostics and personalized therapeutic approaches.