[A CASE OF AUTOSOMAL DOMINANT POLYCYSTIC KIDNEY DISEASE COMPLICATED WITH HENOCH-SCHÖNLEIN PURPURA NEPHRITIS].

Purpura nephritis and autosomal dominant polycystic kidney disease are relatively rare kidney disorders. We present a case complicated by these two diseases. A 68 year-old man with polycystic kidney disease was referred to our hospital with a high fever lasting 3 days and pyuria. Pyelonephritis was suspected based on computed tomography findings of bilateral swelling of the kidney. Inflammation subsided gradually after the initiation of antimicrobial therapy. However, approximately 3 weeks later, the patient developed a fever and skin purpura on the extremities, stomach colic pain, gross hematuria, and increased proteinuria was evident. Therefore, we diagnosed Henoch-Schönlein purpura complicated with nephritis based on biopsies of the skin and the kidney. Immunosuppressant therapy was administered; every symptom was relieved and proteinuria decreased for approximately 20 months.