Comp Arative Study Of Diagnostic Techniques Of Cryptosporidiosis In Diarrheic Children:

Asmaa Abdel Moniem El Kholy

This study was carried out on 80 diarrheic children of different ages who are divided into two groups:1- Immunocompromised group:Including 40 Immunocompromised diarrheic children.2- Immunocompetent group:Including 40 Immunocompetent diarrheic children.Stool samples were collected from these diarrheic children and Cryptosporidium parvum was examined in these stool samples by the following:1) Macroscopic examination.2) Microscopic examination including:a- Direct smear.b- Concentration method using Sheather’s sugar cover slip floatation method.c- Preparation of fixed smears.d- Staining of the smears by modified Ziehl-Nelsen stain3) ELLSA technique for coproantigen detection.Based on the results of the present study, it can be concluded that:1- Cryptosporidium spp is an important cause of diarrhea in children under six years of age especially the immunocompromised children.2- Cryptosporidium infection is insignificantly more prevalent in males than females.3- Abdominal pain and loss of weight are the main presenting symptoms among all Cryptosporidium infected cases after diarrhea.4- The highest rate of infection was detected among patients with diarrhea of 5 - < 10 motions day.5- 100% and 33.33% of the Cryptosporidium infected cases by ELISA and MZN respectively have more than two previous attacks of diarrhea.6- Breast feeding in the first two years of life has a protective effect against cryptosporidial infection. Consumption of contaminated food and water by artificially fed children brought them to be susceptible to infection by Cryptosporidium spp. This explains high percentage of artificially fed children having Cryptosporidium spp infection compared with those who are breast fed.7- 20% and 7.5% of the Cryptosporidium infected cases by ELISA and MZN respectively were immunocompromised.8- 1% of the infected diarrheic cases by ELISA gave history of animal contact. This proves the zoonotic nature of cryptosporidiosis but it also shows that animal contact is not the only possible mode of transmission of cryptosporidiosis.9- The percentage of infection was higher in patients having tape water supply suggesting the possibility of contaminated tape water.10- Regarding diagnostic methods, the enzyme linked immunosorbent assay proved to be more sensitive and specific than the modified Ziehl-Nelsen staining technique. It is a good negative test as the negative predictive value was 100%, however, the positive predictive value was 27.27%, so it needs further confirmation.