Primary subcutaneous hydatid cyst in the left distal thigh.

Human cystic echinococcosis, a zoonotic infection caused by Echinococcus granulosus, remains a largely extended public health problem in endemic regions. Hydatid cyst disease can occur in all viscera and soft tissues, although the liver and the lungs are the most commonly involved organs. Primary hydatid disease of the soft tissue is extremely rare, even in endemic areas, and accounts for 0.5-5.4 % of all hydatid disease cases, with very little data on the incidence of subcutaneous echinococcosis. The paper will be focused on analyzing this extremely rare disease. A 14-year-old girl came to our Department of pediatric Surgery with a painless, round, palpable mass in the subcutaneous tissue of the distal anteromedial side of the left thigh. Based on clinical and laboratory findings and imaging techniques, we suspected a hydatid cyst. She was treated successfully with complete cyst excision. The macroscopic appearance suggested a hydatid cyst. Histopathologic examination of the specimen revealed a hydatid cyst. No other organ involvement has been detected. Hydatid disease should be considered in the differential diagnosis of all cystic masses in all anatomic locations, especially in regions where the disease is endemic.