Antiphospholipid Syndrome in a Patient With IgA Nephropathy: A Rare and Challenging Clinical Overlap.

Antiphospholipid syndrome (APS) is a rare autoimmune condition associated with a heightened risk of blood clots in arteries and veins due to the presence of specific antibodies. IgA nephropathy (IgAN), a kidney disorder involving immune complex deposition, is another immune-mediated disease. The coexistence of APS and IgAN is highly uncommon. We describe a young adult male with biopsy-confirmed kidney involvement who developed a significant clot in the lower limb. Despite appropriate treatment, the clot progressed, leading to complications in the lungs. Further investigation revealed laboratory findings consistent with APS. The patient underwent advanced interventions including clot removal and vascular procedures, followed by long-term treatment to prevent further clotting. This study emphasizes the clinical complexity when these two immune-mediated conditions overlap and underscores the importance of early detection and collaborative care in managing such rare and serious presentations.