Tehran University of Medical Sciences Case Reports in Clinical Practice 2538-2683 11 2 2026 08 29 61 66 Sepideh Aarabi Department of Emergency Medicine, Sina Hospital, Tehran University of Medical Sciences, Tehran, Iran. 2025 11 18 2026 07 15 A 28-year-old woman with poorly controlled type 1 diabetes mellitus (T1DM) presented with a two-week history of fever, left lower back pain, and progressive difficulty walking. Imaging confirmed the concurrent presence of a left iliopsoas abscess and left hip septic arthritis—an exceedingly rare combination. The abscess was treated with CT-guided percutaneous catheter drainage, and the hip joint infection was managed with open arthrotomy and irrigation. Culture of aspirated material identified methicillin-resistant Staphylococcus aureus (MRSA). Treatment was completed with a six-week course of targeted intravenous vancomycin and concurrent optimization of glycemic control. Complete clinical, laboratory, and radiological resolution was documented at six months. This case highlights that clinicians should maintain a high index of suspicion for concurrent deep-seated infections in diabetic patients presenting with musculoskeletal symptoms and fever. MRI is the imaging modality of choice for delineating both pathologies simultaneously, and successful management necessitates a multidisciplinary approach integrating surgical drainage, pathogendirected antimicrobial therapy, and metabolic optimization. https://crcp.tums.ac.ir/index.php/crcp/article/view/1139 https://crcp.tums.ac.ir/index.php/crcp/article/download/1139/780