Non-vertebral hydatidosis in bone: Difficulties in management

OBJECTIVES: This study presents our experience in surgical treatment of extravertebral bone hydatidosis and aims to investigate the utility of specific immunoglobulin E (IgE) in diagnosis and prognosis of the disease. PATIENTS AND METHODS: Between January 1990 and December 2019, a total of 10 patients (6 males, 4 females; mean age: 47.2±14.7 years; range, 27 to 71 years) with non-vertebral bone hydatidosis surgically treated in our hospital were retrospectively included. Curettage or wide resection was performed in all cases, followed by medical antihelminthic therapy. Specific IgE p2 was studied in seven patients during and at final follow-up. RESULTS: At the time of diagnosis, secondary infection of the cyst was observed as the initial symptom in two patients mimicking an abscess and, in both cases, more surgeries were required without final healing. In two cases, over five specific IgE presented a false negative at the time of diagnosis and it was not correlated with clinical evolution in three cases over seven. In six cases, diagnosis was obtained before surgery. In treatment, pelvic disease had the worst prognosis (none healed) and bacterial overinfection was a common complication after surgery. At the final follow-up, only two femoral cases (20%) were free of disease. Other four cases (three in iliac bone, one in proximal femur) needed several surgeries without healing. The other four patients showed no progression or refused a new surgical treatment. CONCLUSION: Location, bone defect, when it is possible to perform a radical surgery, and associated bacterial overinfection after surgery make cystic hydatidosis in bone an infection very difficult to treat definitively in humans. Negative specific IgE does not exclude bone hydatidosis.