Evaluation of interferon gamma release assay using mycobacterium tuberculosis antigens for diagnosis of pulmonary tuberculosis in BCG vaccinated population of Kelantan, Malaysia

Hajar Fauzan, Ahmad (2013) Evaluation of interferon gamma release assay using mycobacterium tuberculosis antigens for diagnosis of pulmonary tuberculosis in BCG vaccinated population of Kelantan, Malaysia. Masters thesis, Universiti Malaysia Pahang (Contributors, UNSPECIFIED: UNSPECIFIED).

[img]
Preview
Pdf
Evaluation of interferon gamma release assay using mycobacterium tuberculosis antigens for diagnosis of pulmonary tuberculosis in BCG vaccinated population of Kelantan, Malaysia.pdf

Download (327kB) | Preview

Abstract

Although Malaysia is an intermediate tuberculosis (TB) burden country, the absolute number of new cases has been increasing recently. Improvement in early diagnosis followed by efficient chemotherapy is the major control strategy for TB. Currently, T-cell based interferon-gamma release assays using Mycobacterium tuberculosis (MTB) antigens from QuantiFERON®-TB Gold In-Tube (QFT-GIT) assays have shown unclear values in terms of sensitivity and specificity in the diagnoses of active pulmonary and latent TB infections. For this study, two MTB antigens known as VacIII and Ubi-VacIII were evaluated for their diagnostic potential based on dynamic T-cell responses among BCG-vaccinated populations were investigated. Thirty-six patients with active pulmonary TB and 38 healthy controls (HC) from a selected hospital in Kelantan, Malaysia were recruited and tested by using gold standard assays and IGRA. The sensitivity and specificity of QFT-GIT, VacIII and Ubi-VacIII antigens among BCG vaccinated population were 30.4% and 88.9%, 47.8% and 55.6%, and 30.4% and 18.5%, respectively. Even though the overall agreement between IGRA and the gold standards assays showed fairly poor correlation (K values=0.320), the T-cell responses against the antigens were considered statistically significant (P<0.001).' In conclusion, all the 3 antigens were unable to discriminate between TB and HC due to high variability of the sensitivities and specificities they demonstrated. As compared to VacIII and UbiVaclll, QFT-GIT showed better specificity however its low sensitivity was expected due to the fact that the TB7.7 antigen is absent in clinical MTB strains of South East Asia.

Item Type: Thesis (Masters)
Additional Information: Thesis (Master of Science) -- Universiti Malaysia Pahang - 2013
Uncontrolled Keywords: Tuberculosis Microbiology; Tuberculosis Pathogenesis; Mycobacterium tuberculosis pathogenicity; Tuberculosis physiopathology
Subjects: Q Science > Q Science (General)
Q Science > QR Microbiology
Depositing User: Ms. Nurezzatul Akmal Salleh
Date Deposited: 16 Nov 2016 02:02
Last Modified: 24 Nov 2021 02:05
URI: http://umpir.ump.edu.my/id/eprint/15317
Download Statistic: View Download Statistics

Actions (login required)

View Item View Item