Terminal ileitis associated with Blastocystis hominis infection.

We report on the previously unobserved clinical presentation of terminal ileitis secondary to Blastocystis hominis in a 37-yr-old white male. When the patient was treated with metronidazole, the symptoms improved and the radiographic abnormalities resolved. We believe that this is the first well-documented instance of terminal ileitis secondary to B. hominis.