Treatment of a ruptured hydatid cyst of lung with mebendazole.

Mebendazole was given prophylactically to a patient with a ruptured pulmonary hydatid cyst before surgical excision of the cyst. The cyst size was reduced by half and there was no radiological or immunological evidence of the presence of active secondary disease 15 months after rupture. The primary cyst was invaded by fungal hyphae, probably Aspergillus, and the danger of abscess or mycetoma formation if surgery is not carried out after chemotherapy is emphasized.