Intra-cystic drug concentration of albendazole sulphoxide in patients with Echinococcus granulosus cysts.

Albendazole therapy--alone or in combination with surgery--remains the standard of care for human echinococcosis depending on the stage of disease. However, only limited data are available on target site concentrations in liver cysts and data for non-liver cysts are lacking. We report on intra-cystic concentrations of the biologically active metabolite albendazole sulphoxide in non-liver cysts indicating a relative intra-cystic drug concentration of 48-156% compared with plasma levels. These data are evidence for a satisfactory penetration of albendazole sulphoxide into Echinococcus cysts localized in other organs than the liver and underline the usefulness of albendazole therapy for this indication.