Comparative Study of Microscopy and the Rida Quick <i>Cryptosporidium/Entamoeba/Giardia</i> Combi (N1722) Methods in the Clinical Diagnosis of Protozoan Diarrhoea in Benue State, Nigeria.

Abstract

One hundred and five (105) single stool specimens were pooled together from patients of all ages presenting with diarrhoea to hospitals in Benue State, Nigeria. The stool specimens were analyzed using Microscopy and Rida Quick Cryptosporidium / Giardia /Entamoeba Combi (N 1722) methods to determine whether the diarrhoea was as a result of infection with Cryptosporidium parvum, Giardia lamblia and or Entamoeba histolytica. The results showed a positivity of 13 (n=105, 12.38%) single infections and 10 (n= 105, 9.52%) mixed infections by Rida Quick test as against 16(n=105, 15.24%), 11 (n= 105, 10.48%) and 3 (n= 105, 2.86%) infections by microscopy using direct saline wet mount, formalin ether concentration and Ziehl-Nelseen staining methods respectively. The former method was able to detect 5 (4.76%) cases of cryptosporidiosis, 1 (n=105, 0.95%) case of amoebiasis, 7 (n=105, 6.67%) cases of giardiasis as well as 5 (4.76%), 1 (0.95%) and 4 (3.81%) cases of multiple infections with G. lamblia and E. histolytica, C. parvum and E. histolytica and C. parvum, G. lamblia and E. histolytica combined respectively. Three (2.86%) patients were also detected with oocysts of C. parvum by microscopy using Ziehl-Nelseen staining technique. Microscopy by direct saline wet mount and formalin ether concentration methods detected 10 (9.52%) infections with E. histolytica / E. coli and 6 (5.71%) infections with giardiasis as well as 4 (3.81%) with G. lamblia and 7 (6.67%) with E. histolytica / E. coli respectively. The inability of the microscopic methods to detect what was revealed by the antigen detection assay could partly be due to intermittent shedding of parasites by the patients which may be missed in a single stool sample or the skills and experience of the researchers performing the test.

Keywords: Diarrhoea, Cryptosporidium parvum, Giardia lamblia, Entamoeba histolytica, Microscopy, Rida Quick test.