|Values are valid only on day of printing.|
Establishing the diagnosis of intestinal cryptosporidiosis
For other diagnostic tests that may be of value in evaluating patients with diarrhea; the following algorithms are available in Special Instructions:
-Parasitic Investigation of Stool Specimens Algorithm
-Laboratory Testing for Infectious Causes of Diarrhea
Cryptosporidia are protozoa of the coccidian group which are common parasites of livestock animals and can contaminate and survive in surface water supplies.
Infection of humans occurs by the fecal-oral route or by ingestion of contaminated water. The exact mechanism by which the organism causes gastroenteritis is unknown.
Cryptosporidiosis occurs as a profuse diarrhea in patients with AIDS and as a self-limited moderate diarrhea in young children, especially daycare attendees and their relatives.
See Parasitic Investigation of Stool Specimens Algorithm and Laboratory Testing for Infectious Causes of Diarrhea in Special Instructions for other diagnostic tests that may be of value in evaluating patients with diarrhea.
A positive enzyme-linked immunosorbent assay (ELISA) indicates the presence of antigens of cryptosporidium and is interpreted as evidence of infection with that organism.
The sensitivity, specificity, and positive predictive value of the ELISA were 87%, 99%, and 98% respectively, as determined by examination of 231 fecal specimens by conventional microscopy and by ELISA.
Examination of multiple fecal specimens may be required to detect Cryptosporidium.
Soave R, Johnson WD Jr: Cryptosporidium and Isospora belli. J Infect Dis 1988;157:225-229