EVALUATION OF POINT OF CARE TEST FOR DIAGNOSIS OF HUMAN GIARDIASIS

Background: Giardia is a unicellular flagellated parasite infecting wide range of vertebrate hosts, including humans. Infection is usually transmitted through ingestion of cyst stage. Infection occurs worldwide, but particularly affects populations in the developing countries. Giardiasis is usually asymptomatic but, mild to moderate self-limiting diarrhea commonly occurs. In other cases, diarrhea may be severe, prolonged or even life threatening. Aim of the work: The aim of this study was to assess the value and reliability of the immunochromatographic Giardia strip test (RIDAQUICK)* in a routine diagnostic setting as a point of care test for diagnosis of Giardiasis. The results will be compared to those obtained using conventional microscopy and the ELISA test “reference method” (RIDASCREEN)*. Patients and Methods: This cross sectional study was conducted on 30 random stool samples recruited from symptomatic infants and children (<10 years old) of both genders (15 males and 15 females) complaining of gastrointestinal symptoms as diarrhoea, abdominal pain and flatulence. The studied patients were either admitted to inpatient ward of the pediatric hospitals of Ain Shams
University or referred from the outpatient clinic. The samples were processed in the Central Microbiology Laboratory, Clinical Pathology Department, Ain Shams University Hospitals from January 2018 till December 2018. All stool samples were subjected to the following: Macroscopic examination of stool samples by naked eye, microscopic examination by conventional methods (Direct wet mount and iodine mount using ordinary light microscopy), immunochromatographic (ICT) Giardia strips and enzyme linked immunosorbent assay (ELISA). Results: Concerning the diagnostic yield of the used diagnostic methods microscopy and ICT compared with ELISA. ICT as diagnostic test was more efficient test than microscopy with higher accuracy (93%) to detect Giardia in all study individuals. Kappa agreement showed that there was 0.85 (almost perfect agreement between ICT with ELISA findings) and 0.66 (Substantial agreement between microscopy and ELISA). Conclusion: The use Giardia Antigen detection by ICT was found sensitive and specific for the detection of G. lamblia. They are rapid to perform and do not require experienced staff or special technical equipment, results are obtained within 9–10 min per test.