Genotypic analysis of Giardia duodenalis in children at Egypt

Giardia duodenalis is among the most common and frequent intestinal protozoan infecting Egyptian children. The present study aims to identify the genotypic features of G. duodenalis among children fecal samples complaining of diarrhea at Beni-Suef Governorate, Egypt, and to study the association between Giardia assemblages and clinical presentation of the disease among this category. One hundred thirty diarrheic stool samples were subjected to direct stool examination, and positive samples for Giardia were subjected to copro-DNA extraction and amplification targeting the triose phosphate isomerase ( tpi ) gene using nested polymerase chain reaction (nPCR) technique. Then amplified DNA products were purified and sequenced. Out of 36 microscopically positive samples for Giardia , 28 samples were successfully purified and sequenced; subassemblages AII, BIII, and BIV were detected (10.7, 14,3, and 17,8 %, respectively), and it was difficult to subgroup 16 samples that belong to assemblage B (57 %). Children below the age of 6 are significantly 16 times at risk of infection with assemblage B than assemblage A ( p value = .001). Flatulence and presence of fat particles on microscopic examination were significantly associated with infection ( p value = 0.001, 0.027, respectively). However, assemblage B was associated with variations of symptomology than A. The present study focuses on giardiasis among Beni-Suef community. Infection is due to both assemblages: assemblage B is more prevalent (89.3 %) than A (10.7 %) and assemblage AI was not recorded. More studies are needed to identify source of infection.