Non-tuberculous cold abscess of the psoas muscle--an unusual manifestation of colocutaneous fistula.

We report here a case of colocutaneous fistula drained from the retroperitoneal space mimicking a cold abscess of the psoas muscle. A 60-year-old diabetic woman with a 6-year history of a chronic draining sinus over her right thigh had been treated intermittently with antibiotics. At presentation, she had no systemic toxic signs nor other constitutional symptoms. The patient was inadequately managed by curettage at first under the tentative diagnosis of tuberculous cold abscess. After the correct diagnosis of colocutaneous fistula, right nephrectomy and right hemicolectomy with ileotransverse colostomy were done. The patient was well 5 years later without recurrence. This is an atypical presentation of enterocutaneous fistula in an immunodeficient patient that should be emphasized to facilitate the correct diagnosis and early treatment.