Evaluation of Three Laboratory Methods for Diagnosis of Giardia duodenalisin children under seven years old

Abstract

Different methods are used for the diagnosis of giardiasis and need to be evaluated for their applicability in laboratory routine. This study evaluated the effectiveness of three different methods for detecting Giardia duodenalis in fecal samples from children living in a poor area. Stool samples from 89 children aged under seven years were tested for Giardia by direct parasitological examination (DPE), immunochromatographic test (ICG), and real-time quantitative PCR (qPCR). Positive result was obtained for 22 samples using DPE, 26 using qPCR, and 38 using ICG. The tests showed conflicting results with different sensitivities and specificities, with the ICG test having the highest sensitivity but lower specificity than the qPCR. However, the qPCR detected the parasite in seven additional samples. It is necessary to use alternative methods for Giardia detection. We recommend ICG for Giardia diagnosis when the material is insufficient for microscopic analysis, particularly in cases of clinical suspicion.