A case of pelvic bone hydatidosis--diagnosis and treatment

Echinococcosis is a frequent helminthiasis in Bulgaria. Hydatid cysts commonly affect the liver and the lung. Echinococcosis rarely involves bones (0.5 to 2.5%) and vertebral column is affected in 50% of the cases.

We report a case of a 67-year-old female with echinococcosis of the pelvic bone clinically manifested by pain and swelling of the right iliac region and complicated by abscess of the surrounding soft tissue. The patient underwent surgery at the Department of Orthopedics and Traumatology, University hospital "St. George", Medical University, Plovdiv. Diagnosis was based on imaging findings, serologic and histological methods. Biopsy material was investigated by standard histological methods hematoxilin-eosin (H-E),PAS and hydrargyrum impregnation after Gommori, which presented both chitin and germinative membranes of the hydatid cyst.

The patient underwent complete resection of the bone lesion along with the surrounding soft tissue. Purulent collection of 1200 ml was evacuated. A six months follow-up of the patient revealed no pathology of the cyst and other organs. She walked unaided. No echinococcosis recurrence was observed on control examinations.

Hydatid bone disease is usually difficult to diagnose. Its treatment includes excision of bone lesion, curettage and oral therapy. It is not always possible to fully remove all the affected bone fragments especially when cysts are located in the femoral and pelvic bones. In the reported case the hydatid cyst was fully removed by resection of the right iliac ala and the patient's mobility was preserved.