Abstract :
Background: Cyclospora cayetanensis causes human intestinal cyclosporiasis. It is more common in the immunocompromised patients and mainly seen in people living with HIV/AIDS (PLHA), post-renal transplant (PRT) patients and immunocompromised children (IC). Diagnostic microscopy for the oocysts of the parasite is less sensitive, requiring examination of multiple stool samples. Here we developed a new single run polymerase chain reaction (PCR) assay for the detection of C. cayetanensis and it was used to know the hospital based prevalence of cyclosporiasis.
Materials and Methods: A cross-sectional study was conducted from June 2016 to October 2020 in a tertiary care teaching hospital. A new single run amplification PCR-based diagnostic assay was developed for C. cayetanensis. Stool samples were collected from 121 PLHA, 135 PRT and 79 immunocompromised children (IC) other than PLHA and PRT. All stool samples were examined for the presence of C. cayetanensis oocysts as well as tested with new C. cayetanensis PCR assay.
Results: Modified Ziehl-Neelsen staining of the concentrated stool smear did not reveal oocysts of Cyclospora species in any stool specimen. However, new PCR assay detected C. cayetanensis in 2 stool specimens – one from a PLHA patient and another from a PRT patient, giving a prevalence of 0.6% (2/335), 0.8% (1/121) in PLHA and 0.7% (1/135) in PRT. It was not detected in IC.
Conclusion: Cyclosporiasis is infrequent in southern part of India. The new single run PCR assay developed by us is simple and cost effective molecular assay for the detection of C. cayetanensis.
Keyword :
Cyclospora cayetanensis, Diarrhea, PCR assay, People living with HIV/AIDS, PLHA, Post–renal transplant, PRT, Modified Ziehl-Neelsen staining