Successful Treatment of Metronidazole- and Albendazole-Resistant Giardiasis with Nitazoxanide in a Patient with Acquired Immunodeficiency Syndrome

A case of metronidazole- and albendazole-resistant giardiasis in a patient with the acquired immunodeficiency syndrome was successfully treated with nitazoxanide (1.5 g twice a day for 30 days). Animal studies and in vitro assays showed that the isolate was resistant to both metronidazole and alben-dazole and susceptible to nitazoxanide. Giardiasis is a common cause of diarrhea in HIV-infected pa-tients [1]. Although metronidazole and/or albendazole therapy is often effective, treatment failure due to chemoresistance oc-curs more and more frequently. Here we describe the successful management of infection with metronidazole- and albendazole-resistant Giardia duodenalis in an HIV-positive patient by use of nitazoxanide. Nitazoxanide, a thiazolide compound, exhibits antimicrobial properties against anaerobic bacteria as well as against helminths and protozoa, including Giardia [2]