[Clinical and epidemiological characteristics of blastocystis hominis]

Blastocystis hominis is an intestinal parasite known since long. It is cosmopolitan and lives in the colon. It is still the subject of controversy regarding its pathogenicity and possibly opportunistic character.

We exhibit in this article the results obtained for 4 years on the epidemiological, clinical and biological character and opportunistic Blastocystis hominis, often overlooked in the examination of parasitological laboratories city.

This is a retrospective study of 3257 stool examination (PSE), performed in the Mycology Laboratory of Parasitology of the Charles Nicolle Hospital in Tunis over a period of 4 years (January 2005-December 2008). Detection of Blastocystis hominis has been made by microscopic examination of samples by direct examination and concentration.

Blastocystis was found in 7.27% of cases and 48.5% in men. Endolimax nanus is the parasite most frequently associated with Blastocystis (40.4% of cases). The port was symptomatic in 72.1% of cases, diarrhea is the symptom most often found (27.7%). There is a seasonal distribution; in fact, it is more frequently diagnosed in summer and autumn.

The absence of gravity and the saprophytic nature of this infection do not lead to an indication for treatment even among profoundly immunosuppressed individuals. Only the persistence of clinical disorders associated with the detection of the parasite and in the absence of other micro-organisms and intestinal parasites justifies the treatement. Metronidazole is the molecule used conventionally.