Medical treatment of liver hydatidosis.

There are currently three treatment options for liver hydatidosis: urgery, which remains the mainstay of radical treatment; ultrasound-guided aspiration (puncture/aspiration/injection/reaspiration--PAIR); and chemotherapy with benzimidazole compounds (albendazole and mebendazole). Chemotherapy is a noninvasive treatment and is less limited by the patient's status than surgery or PAIR but is not ideal when used alone. Albendazole, the drug most often used, appears to have the greatest efficacy of any agent used so far; nevertheless, apparent cure (shrinkage or disappearance of cysts) ranges only between 20% and 30% of cases. The possible contribution of perioperative chemotherapy offers the prospect of preventing recurrent disease, but it requires more clinical trials to establish that pre- or postoperative chemotherapy does prevent recurrence. The main adverse events are related to changes in liver enzyme levels and bone marrow suppression. About 10% to 20% of patients develop self-limited, reversible rises in transaminase levels; clinically severe pancytopenia or agranulocytosis is exceptional. Alopecia is observed during long-term treatment with albendazole. In all cases these events disappear once treatment is interrupted. According to the World Health Organization guidelines, chemotherapy is the preferred treatment when the disease is inoperable, when surgery or PAIR is not available, or when the cysts are too numerous. Another important indication for chemotherapy is the prevention of secondary echinococcosis. There is not yet formal consensus, as the efficacy and safety of some of the methods require further evaluation before we can establish comprehensive guidelines for the medical treatment of hydatidosis.