Investigation of the Cryptosporidium in immune suppressed individuals by using modified acid-fast stainnig and ELISA methods

Abstract

Cryptosporidium sp. is a protozoon and one of the causes of gastroenteritis. Since it is resistant to chlorine and passes through the filters of the drinking water, it has a high prevalence in the water sources and it may cause water-borne epidemics due to its ability to cause infection even with only a few numbers of parasites. In this study, in Medical Microbiology Department Laboratory it was aimed to investigate Cryptosporidium antigens in the stools of immunocompromised patients who were in the risk group and in the stools of immunocompetent patients who were in different age groups and had diarrhea. In this study, Cryptosporidium sp. antigens were investigated by ELISA method and Cryptosporidium oocysts were searched for with modified acid-fast staining. The sensitivity and specificity of the methods used in the study were investigated. Material and Methods: In this study, fecal samples of 275 immunocompromised patients from oncology (n=156) and dialysis (n=98) departments as well as children with malnutrition (n=21) and fecal samples of 200 immunocompetent patients with the complaints of gastroenteritis from gastroenterology (n=22) and pediatrics departments (n=178) were studied. Stool samples of 55 immunocompetent patients without diarrhea from different clinics were enrolled as the control group in the study. Stool samples of each patient was prepared for macroscopic solid-lamella preparation and stained with modified acid-fast stain and examined for Cryptosporidium and other intestinal parasites. In addition, Cryptosporidium sp. antigens were investigated with Prospect Cryptosporidium stool ELISA kit (OXOID). Results: In this study, Cryptosporidium sp. oocysts were detected using modified acid-fast staining in 17 (3.2%) and Cryptosporidium sp. antigen was detected in stools of 31 (5.8%) patients by using ELISA method among 530 stool samples. Most of the patients in whom Cryptosporidium sp. detected were immunosuppressed and older than 40 years. The sensitivity of modified acid-fast staining method was 54.83% and its specificity was 100% while both sensitivity and specificity of the ELISA method were detected as 100%. A variety of protozoan cysts were detected in 61 (11.5%) and Hymenolepis nana eggs were detected in 3 (0.5%) of the samples by using Native-Lugol preparation. Conclusion: ELISA method together with modified acid fast staining would be suitable for routine use to investigate Cryptosporidium in immunosuppressed patients and also in normal patients suffering from gastroenteritis. © 2012 by Türkiye Klinikleri.