Comparison of ELISA, nested PCR and sequencing and a novel qPCR for detection of Giardia isolates from Jordan.

Abstract

Little is known about the prevalence of Giardia duodenalis in human patients in Jordan and all previous studies have used direct microscopy, which lacks sensitivity. The present study developed a novel quantitative PCR (qPCR) assay at the β-giardin (bg) locus and evaluated its use as a frontline test for the diagnosis of giardiasis in comparison with a commercially available ELISA using nested PCR and sequencing of the glutamate dehydrogenase (gdh) locus (gdh nPCR) as the gold standard. A total of 96 human faecal samples were collected from 96 patients suffering from diarrhoea from 5 regions of Jordan and were screened using the ELISA and qPCR. The analytical specificity of the bg qPCR assay revealed no cross-reactions with other genera and detected all the Giardia isolates tested. Analytical sensitivity was 1 Giardia cyst per μl of DNA extract. The overall prevalence of Giardia was 64.6%. The clinical sensitivity and specificity of the bg qPCR was 89.9% and 82.9% respectively compared to 76.5 and 68.0% for the ELISA. This study is the first to compare three different methods (ELISA, bg qPCR, nested PCR and sequencing at the gdh locus) to diagnose Jordanian patients suffering from giardiasis and to analyze their demographic data.

• Authors: Nawal Hijjawi, Rongchang Yang, Ma'mon Hatmal, Yasmeen Yassin, Taghrid Mharib, Rami Mukbel, Sameer Alhaj Mahmoud, Abdel-Ellah Al-Shudifat, Una Ryan
• Journal: Experimental parasitology (Exp Parasitol) Vol. 185 Pg. 23-28 (Feb 2018) ISSN: 1090-2449 [Electronic] United States
• PMID: 29309786 (Publication Type: Journal Article)
• Copyright: Copyright © 2018 Elsevier Inc. All rights reserved.

Chemical References

• Antigens, Protozoan
• Cytoskeletal Proteins
• DNA, Protozoan
• Protozoan Proteins
• giardin protein, Giardia lamblia
• Glutamate Dehydrogenase

Topics

• Adolescent
• Adult
• Antigens, Protozoan (analysis)
• Child
• Child, Preschool
• Colic (parasitology)
• Cytoskeletal Proteins (genetics)
• DNA, Protozoan (chemistry, isolation & purification)
• Diarrhea (parasitology)
• Enzyme-Linked Immunosorbent Assay
• Feces (parasitology)
• Female
• Giardia lamblia (genetics, immunology, isolation & purification)
• Giardiasis (epidemiology, parasitology)
• Glutamate Dehydrogenase
• Humans
• Infant
• Jordan (epidemiology)
• Male
• Middle Aged
• Polymerase Chain Reaction
• Prevalence
• Protozoan Proteins (genetics)
• Real-Time Polymerase Chain Reaction
• Sensitivity and Specificity
• Vomiting (parasitology)
• Young Adult