Cutaneous fistula of liver echinococcal cyst previously misdiagnosed as fistulizated rib osteomyelitis.

External fistulization or subcutaneous rupture of liver echinococcal cyst (EC) is found occasionally with total of 15 cases reported in the literature. We report a case of 60-year-old female previously misdiagnosed as fistulizated osteomyelitis of the 11(th) rib. At computed tomography scan, non-vital EC was noted in the third liver segment. Under suspicion of external fistulization of perforated EC the patient underwent one-stage operation-pericystectomy and complete fistula excision. A retrospective analysis of the reported cases in the literature was performed with special references to classifying this rare entity. The main purpose of this report is to highlight the possibility of such a diagnosis when cutaneous fistula occurs in a same anatomic area with hydatid EC, even that cyst is proven to be calcified. We emphasize the role of a swift and radical surgical procedure including complete fistula excision to prevent secondary dissemination and post-operative complications.