Cyclospora: Introduction, Classification, Morphology, Pathogenicity Lab Diagnosis, Treatment, Prevention and Keynotes

Introduction of Cyclosphora

Cyclosphora cayetamensis is a coccidian parasite and it is a very new parasite first identified and was described by Ortega Gilonan and Sterling in 1994. It creates a pathogenic effect called cyclosporiasis.

Classification of Cyclosphora

• Domain: Eukaryota
• Phylum: Apicomplexa
• Subphylum: Eimeriida
• Class: Conoidasida
• Subclass: Coccidiasina
• Order: Eucoccidiorida
• Suborder: Eimeriorina
• Family: Eimeriidae
• Genus: Cyclospora
• Species: C. cayetamensis

Geographical Distribution of Cyclosphora

C. cayetamensis has been reported from several countries including the USA, Peru
Nepal and UK but these days it is found anywhere. It is inhabited in the upper small intestine, duodenum, and jejunum.

Morphology of Cyclosphora

Cyst of C. cayetanesis is non-retractile, spherical to oval, slightly wrinkled bodies measuring 8-10 µm in diameter. They contain two ovoid sporocysts, 4 × 6 µm in size. Each sporocyst contain two sporozoits. Thus each sporulated oocyst contains four sporozoites. Unlike cryptosporidial oocysts, they have a much thicker oocyst wall and their contents are more granular than those of cryptosporidial oocysts.

Life Cycle

Unsporulated oocysts are excreted in the feces. Sporulation occurs outside the body. Man acquires infection by ingestion of food and water contained with feces containing oocysts. The life cycle of Cyclospora, although not completely understood, is thought to be similar to that of Cryptosporidium species.

Pathogenicity of Cyclosphora

It causes diarrhea, fever, fatigue. Abdominal cramps are associated with poor sanitation.
Infection is more severe in immunocompromised patients, especially with AIDS.

Symptoms of Cyclosporiasis

Symptoms of Cyclosporiasis is as follows-

• Watery diarrhea
• Loss of appetite
• Weight loss
• Stomach cramps or pain
• Bloating
• Increased gas
• Nausea
• Fatigue
• Headache
• Low-grade feve

Laboratory Diagnosis of Cyclosphora

1. Direct Microscopy: Diagnosis can be made by stool microscopy.
2. Staining: Oocysts of Cyclospora cayetanensis are acid-fast (modified Ziehl-Neelsen staining) and stain with a faint pink-red color while older cells may fail to stain while oocysts stain orange-red with safranin.
3. Histopathological examination: Duodenal and jejunal biopsy assay
4. Molecular Assay-Cyclospora cayetanensis Real-Time PCR Detection Method
   

Treatment

The antibiotic co-trimoxazole (trimethoprim-sulfamethoxazole) is recommended in the management of serious infections.

Prevention

• Avoiding water or food that might have been contaminated with stool/ feces may help prevent cyclosporiasis.
• Keep in practice washing hands with soap and warm water before and after handling or preparing fruits and vegetables.

Keynotes on Cyclosphora

• The size of parasite is 8-10 µm and the site in host are small intestine, duodenum, and jejunum.
• Mode of infection is feco-oral route and the causative agent is ocyst.
• Cyclopora infection may occur in anyone who ingests contaminated food or water.

Further Readings

• https://www.cdc.gov/dpdx/cyclosporiasis/index.html
• https://www.nhs.uk/conditions/cyclospora/
• https://www.mayoclinic.org/diseases-conditions/cyclosp
• Merkell and Voge’s medical parasitology-9th edition.
• Parasitology: 12th edition- K. D. Chatterjee
• Isenberg clinical microbiology procedures Handbook-2nd edition. Vol. 2
• Medical Parasitology by Abhay R. Satoskar, Gary L. Simon, Peter J. Hotez and Moriya Tsuji
• Atlas of Human Parasitology, Lawrence R Ash, Thomas C. Orihel, 3 rd ed, Publisher ASCP Press, Chicago.
• Molecular Medical Parasitology. Editors: J. Joseph Marr, Timothy W. Nilsen, and Richard W. Komuniecki, Publisher Academic Press, an imprint of Elsevier Science.