ABSTRACT
Isospora belli is a coccidian protozoon that can cause serious diarrhea especially in immunocompromised patients. The laboratory diagnosis depends primarily on the identification of oocysts in stool specimens by direct microscopic examination with iodine or special stains. This case is presented in order to draw attention to isosporiasis among the diarrheas that can be seen in elderly patients with several chronic diseases. A 81 year-old debilitated male, who had a history of hypertension, Alzheimer’s disease, previous cerebrovascular accident and right hemiplegia, was admitted to our hospital complaining of malaise, anorexia, chills, abdominal pain, dysuria, cough, sputum and diarrhea of ten days duration. I. belli oocysts were detected by microscopic examination of the sample with iodine after concentration by formalin-ethyl acetate sedimentation. Then, modified acid-fast and trichrome stains were performed and I. belli oocysts were detected with both methods. Similar to this case, infections caused by I. belli can occur in elderly immunocompromised patients with several chronic diseases and inadequate nutrition and care. Consequently, in individuals with persistent diarrhea, examinations and tests should be carried out by taking their immune status into consideration and stool examinations should be done at frequent intervals using the concentrations methods and special stains.(Turkiye Parazitol Derg 2013; 37: 222-4)