ELECTRON-MICROSCOPIC CHANGES IN ENTEROCYTOZOON-BIENEUSI FOLLOWING TREATMENT WITH ALBENDAZOLE

Aim-To identify and describe electron microscopic changes occurring in Enterocytozoon bieneusi in patients treated with albendazole. Methods -Eighteen HIV seropositive patients with E bieneusi infection of the s mall intestine were treated with albendazole 400 mg twice a day for on e month. Duodenal biopsy specimens obtained before and at the end of t reatment were examined electron microscopically by a pathologist who w as unaware of the clinical response. A semiquantitative assessment of the parasite load and description of the parasite morphology was made. Results-A complete resolution of diarrhoea occurred in nine patients and a further three had a greater than 50% reduction in baseline stool frequency or volume. Three of the non-responders were also infected w ith cryptosporidium. There was a reduction in parasite load in those r esponding to treatment and an increase in abnormal forms in both respo nders and non-responders. Conclusion-The clinical response to albendaz ole treatment seen in some patients with small intestine microsporidio sis may be due to damage to the developmental stages, causing a partia l inhibition of parasite reproduction.