Irregular shedding of Blastocystis hominis

The shedding pattern of the protozoan parasite, Blastocystis hominis, is in vestigated in man and in experimental animal infections. The shedding patte rn of the vacuolar and cystic forms of Blastocystis hominis in infected ind ividuals have been shown in the present study to be irregular. The study sh ows that there is marked fluctuation in the shedding of the parasite from d ay to day, varying from as high as 17 to 0 per x40 microscopic held. The cy stic stages when estimated in 8 Blastocystis-infected individuals ranged fr om as high as 7.4 x 10(5) cysts per gram of stool to 0. The shedding of cys tic and vacuolar forms observed over a period of 20 days in experimentally- infected Wistar rats were not only shown to be irregular but the amount var ied from host to host. The study has important diagnostic implications in t hat the stool samples must be collected more than once from patients showin g clinical signs and symptoms to eliminate the cause of it to Blastocystis. The study also shows that there are asymptomatic individuals who pass a la rge amount of cysts as such individuals should be treated to prevent transm ission to others.