Diagnosis of Ascaris sp.in Human by Using Molecular Technique

Abstract

This study aimed to Diagnose of Ascaris sp.in human by using molecular technique. Microscopically looking for Ascaris sp. eggs, human faeces were collected from 120 patients admitted to private clinic in Baghdad, Iraq. The Kato-Katz method (Hell-Tec kit) was used for the parasitological diagnosis. DNA Stool Mini kit (Qiagen) was used to process 200 l of material, although with some adjustments (Proteinase K digestion at 55-60 °C for 4 h). To determine whether typical PCR inhibitors found in faeces were present, human DNA PCR was carried out. The cytb gene and ITS1 (480 bp) were used for molecular detection of this parasite. The genotypes of Ascaris need to be amplified and identified. The most reliable method for diagnosing Ascaris intestinal infections is the detection of parasite eggs in faecal samples using a light microscope. The percentage of Ascaris spp. by microscopical method was 2.5 %. The molecular results showed that cytb gene was showed in 16 samples, while ITS1 gene were showed in 18 samples.

In conclusion, the molecular method showed higher sensitivity in diagnosis of Ascaris spp. from human feces when compared with microscopical method.