Interpretive Handbook

Test 81506 :
Cyclospora Stain

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

In recent years, Cyclospora cayatenensis has been shown to cause (in humans) gastroenteritis characterized by watery diarrhea and systemic symptoms such as anorexia, malaise, weight loss, and general debilitation.


The organism which was originally thought to be a cyanobacteria or blue-green algae is now recognized as a protozoan parasite belonging to the coccidian group. It is similar in morphology and staining to Cryptosporidium but is approximately twice as large.


Diarrhea caused by Cyclospora has been reported in Nepal, the Indian subcontinent, Southeast Asia, and Latin America.


It has been extensively studied in Peru and the species name derives from the university where this work was done.


Although most cases of cyclosporiasis have been seen in travelers to developing countries, a focal outbreak due to contaminated water occurred at a Chicago medical center in 1990. Also, in the summer of 1996, a widespread outbreak occurred in many areas of the United States and Canada due to the importation of contaminated raspberries from Guatemala.


Transmission is probably fecal-oral and can be food borne or water-borne.


The infection is usually self-limited but symptoms can be prolonged. The infection usually responds to treatment with a sulfa-trimethoprim combination.

Useful For Suggests clinical disorders or settings where the test may be helpful

The identification of Cyclospora as a cause of infectious gastroenteritis


See Parasitic Investigation of Stool Specimens Algorithm in Special Instructions for other diagnostic tests that may be of value in evaluating patients with diarrhea.

Interpretation Provides information to assist in interpretation of the test results

A report of Cyclospora species indicates the presence of this parasite in the patient's feces.

Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

The full spectrum of disease and the extent of carriage without disease have not been determined. In addition, the exact sensitivity and specificity of the stain have also not been determined.


Cryptosporidium also stain acid-fast although they are much smaller than Cyclospora. Cryptosporidium can be specifically identified using the antigen detection enzyme-linked immunosorbent assay (ELISA).

Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.


If positive, reported as Cyclospora species

Clinical References Provides recommendations for further in-depth reading of a clinical nature

Soave R: Cyclospora: an overview. Clin Infect Dis 1996;23:429-437