infectious diseases
Overview of Intestinal Protozoan and Microsporidia Infections
Diagnosis
Making a diagnosis of intestinal protozoan and microsporidia infections based on symptoms and physical findings is difficult; stool testing for parasite antigens or DNA and microscopic examination of stool for cysts or organisms are necessary. Fecal antigen teststhat are sensitive and specific are available for Cryptosporidiumspecies E. histolytica G. duodenalis Microscopic diagnosismay require several samples, concentration methods, and special stains; thus, the laboratory should be notified which pathogen or pathogens are suspected. Some patients require semi-invasive diagnostic techniques such as endoscopic biopsy (see table). Molecular diagnosisusing polymerase chain reaction-based assays is available for many enteric protozoa. 