VALUE OF MICROSCOPY AND COPROANTIGEN FOR DETECTION OF CRYPTOSPORIDIUM AND GIARDIA IN STOOL SAMPLES

Authors

1 Department of Parasitology, Faculty of Medicine, 6th October University

2 Department of Medical Parasitology, Faculty of Medicine, Cairo University, Egypt

Abstract

Giardiasis and cryptosporidiosis are common protozoa causing gastrointestinal troubles with symptoms
ranged from asymptomatic to long-lasting diarrhea with mal-absorption. The present work was
carried on a total of 96 cases; 62 of them presented with GIT symptoms with or without diarrhea, 50%
of them was previously diagnosed as giardiasis or cryptosporidiosis infected and treated 1-2 months
ago, 11 cases were free from GIT symptoms and 23 cases suffered from chronic debilitating disease as
cancer or renal disease, some of them have previous history of gastro-intestinal disturbances.
The rapid immunochromatographic test (ICT) and copro-ELISA detected G. lamblia and C. parvum
antigens in all fecal samples compared to formol ether concentration and Modified Ziehl-Neelsen
(MZN) staining technique. The sensitivity of G. lamblia in stool samples was 60%, 98.3% & 96.6%
using concentration technique, ICT & ELISA respectively, and specificity was 98.75%, 96.43% &
96.43% respectively. The sensitivity of C. parvum with MZN stain and antigen detection by ICT&
ELISA was 46.2%, 96.4% & 100% respectively. Specificity of the tests in detecting C. parvum was
better than Giardia; 96.4% -100% respectively. All tests have 100% PPV and 80-888% NPV for the
immunological techniques with superiority of ICT over ELISA.

Keywords