Clostridium perfringens-Induced Emphysematous Pyelonephritis: A Diagnostic Challenge With Negative Urine Culture.

is rarely identified as a causative agent of urinary tract infections, and its anaerobic nature creates diagnostic challenges in clinical settings. We report the case of a 59-year-old woman with diabetes mellitus and stage IVA cervical cancer who presented with fever and dyspnea with acute onset, two days following ureteral stent placement. Clinical examination revealed costovertebral angle tenderness and dark red urine. Laboratory findings demonstrated hemolysis, renal dysfunction, and elevated inflammatory markers. Urinary Gram stain revealed Gram-positive rods, and computed tomography demonstrated gas in the right renal pelvis. Blood cultures yielded , yet urine cultures remained negative. The patient developed circulatory collapse requiring intensive care management. Following antimicrobial therapy and stent replacement, she stabilized and was discharged from the intensive care unit after six days. This case highlights as a potential cause of healthcare-associated urinary tract infections in high-risk patients. The occurrence of negative urine cultures despite active infection underscores the necessity for anaerobic culture techniques, while intravascular hemolysis provides valuable diagnostic clues. Clinicians should consider anaerobic pathogens in urinary tract infections with unusual presentations, particularly in patients with malignancy, diabetes, or recent urological interventions.