Isolated Renal Mucormycosis Masquerading as Bacterial Pyelonephritis in a Diabetic Patient: A Case Report.

Isolated renal mucormycosis is a rare, aggressive fungal infection primarily affecting immunocompromised individuals. It often presents diagnostic challenges, mimicking bacterial infections like pyelonephritis. We report the case of a 45-year-old diabetic man presenting with flank pain and fever. Imaging suggested emphysematous pyelonephritis grade 3B. Initial treatment with broad-spectrum antibiotics failed, and blood and urine cultures remained sterile. Nephrectomy revealed angioinvasive mucormycosis. Despite antifungal therapy and nephrectomy, the patient succumbed to the infection. Our case highlights that renal mucormycosis can mimic bacterial pyelonephritis, delaying diagnosis. Clinicians should consider mucormycosis in diabetic patients with persistent symptoms and sterile cultures. Early surgical intervention and antifungal therapy are the mainstay.