Cutaneous Tuberculous Sinus Tract: A Case Report.

An 88-year-old female patient presented with a persistent ulcer in the right flank region following incision and drainage of an abscess. After the relevant examinations and debridement procedures, a deep internal sinus tract approximately 2-3 cm in length was discovered, extending to the lateral border of the external intercostal muscles. Based on local histopathological examination including the tuberculosis PCR, the condition was diagnosed as a cutaneous tuberculous sinus tract caused by Mycobacterium tuberculosis infection. Cutaneous tuberculosis is a relatively uncommon form of extrapulmonary tuberculosis, primarily affecting the skin and subcutaneous soft tissues. The patient has recovered well following an anticipated nine-month course of triple anti-tuberculosis therapy without pyrazinamide. To date, no literature reports have documented persistent deep skin fistulas resulting from this disease.