Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Cyclospora cayetanensis is an apicomplexan protozoan parasite that causes watery diarrhea, anorexia, malaise, and weight loss. The extent of symptoms depends on the age and condition of the host and the infectious dose. The infection is usually self-limited, but symptoms can be severe and prolonged, particularly in immunocompromised patients. Cyclospora diarrheal disease is endemic in many parts of the world, including Asia, India, Southeast Asia, and Latin America. Although most cases of cyclosporiasis have been seen in travelers to developing countries, outbreaks in the United States have been noted due to contaminated fruits and vegetables from Latin America. Transmission is via fecally contaminated food or water. If untreated, symptoms typically last for 10 to 12 weeks, and may follow a relapsing course. The infection usually responds to treatment with a sulfamethoxazole-trimethoprim drug combination.
Cyclospora cayetanensis oocysts are traditionally detected by modified acid-fast staining, in which the oocysts stain bright pink-red. However, the modified Safranin stain has been shown to provide increased sensitivity over modified acid-fast method and produces a more rapid result. It is the method used in our laboratory to detect Cyclospora cayetanensis oocysts in fecal sediment.
The identification of Cyclospora as a cause of infectious gastroenteritis
A report of Cyclospora cayetanensis detected 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 oocysts also stain acid-fast although they are much smaller than the oocysts of Cyclospora cayetanensis. If Cryptosporidium is suspected, the specific enzyme-linked immunosorbent assay (ELISA) for this organism is recommended.
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 detected.
Clinical References Provides recommendations for further in-depth reading of a clinical nature
1. Chacín-Bonilla L: Epidemiology of Cyclospora cayetanensis: A review focusing in endemic areas. Acta Trop 2010;115(3):181-193
2. Ortega YR, Sanchez R: Update on Cyclospora cayetanensis, a food-borne and waterborne parasite. Clin Microbiol Rev 2010;23(1):218-234