False-Positive Results Obtained with the Alexon ProSpecT Cryptosporidium Enzyme Immunoassay

Cryptosporidium is known to cause diarrhea in immunocompromised patients and is also associated with outbreaks of disease due to food-borne and waterborne parasites. Traditional procedures, involving iodine staining of wet mounts of stool sediments and trichrome staining, lack the sensitivity to detect Cryptosporidium. Special staining procedures, such as the modified acid-fast and safranin stains, are generally employed. Less labor-intensive antigen detection assays have simplified detection; however, careful attention to local epidemiology is important because false-positive tests occur. Here, we report two incidents involving 62 false-positive results obtained with the Alexon ProSpecT Cryptosporidium enzyme immunoassay, which were deemed false-positive based on negative results obtained from extensive microscopic examinations.