[Newly established causes of diarrhea: the protozoan Cyclospora cayetanensis (Coccidia, Apicomplexa)]

Coccidia Cyclospora cavetanesis has been considered a saprophytic or accidental infection without special medical significance until 1984. However, epidemics of diarrhea first in Peru and later in USA. Haiti and Nepal have aroused interest in pathogenic characteristics of this parasite and diseases it causes. The study first deals with biological cycle of parasite development as well as clinical picture and treatment, diagnostics and epidemiology of this parasitic disease.

On average the incubation period was 2-11 days with frequent stools (3 or more times a day) without blood or mucus and with tendency for recurrence. The prodromal phase is similar to influenza. It may last several weeks especially in immunodeficient persons (especially patients with AIDS). Trimethoprim (160 mg) and sulfamethoxazole (800 mg) is the treatment of choice, twice a day during a 7 day period, whereas in immunodeficient patients greater doses are necessary during a few weeks, but in such cases individual treatment planning is required. Laboratory diagnosis is made on the basis of microscopic examination of native preparation from the stool, especially if stool concentration procedure is used due to small number of oocysts in the stool. As this method does not provide identification of species, numerous staining methods are recommended (modified Ziehl-Neelsen method, Carbol-Fuchsin and safranine). Epidemiology is still unclear. It is considered that there are two sources of infection: contaminated drinking water and fruits. The disease has a seasonal character and the highest incidence is recorded in late spring and summer months. The infection is caused only by sporozoites developed by sporulation of oocysts under environmental conditions excluding the possibility of direct transmission from one person to another. It is to be expected that further investigations will give answers to numerous questions still open.