Humoral immune response against 38-Kda and 16-Kda mycobacterial antigens in tuberculosis

¹ Microbiology Dept
² Chest Diseases Clinic Training and Research Hospital for Chest Diseases and Chest Surgery, Izmir, TR

^* To whom correspondence should be addressed. E-mail: drshenol{at}yahoo.com.

	Abstract

Several enzyme-linked immunosorbent assays based on mycobacterial antigens have been used for the rapid diagnosis of tuberculosis, although, demonstration of Mycobacterium tuberculosis in a smear or culture is the most reliable method. In this study, diagnostic value of 16-kDa and 38-kDa mycobacterial antigens was investigated in the patients whom they were diagnosed as tuberculosis by clinic and/or bacteriologic findings in Turkey.

Patozym TB complex plus commercial enzyme-linked immunosorbent assay kit was used for measuring IgG against 38 kDa and 16 kDa recombinant antigens. Humoral immune response was analyzed in a group of 179 tuberculosis patients (143 smear-positive, 19 smear-negative, 8 lymphadenitis and 9 pleuritis), 15 inactive tuberculosis cases, and in control groups consisting of 40 healthy volunteers and 20 pulmonary diseases other than tuberculosis.

Sensitivity, specifity, positive predictive value, negative predictive value of the test were detected 52.5%, 93.3%, 95.9%, and 39.7%, respectively in TB cases. Three cases were found positive (20%) in inactive tuberculosis cases.

The ELISA test has presented a very good specifity, an acceptable level of sensitivity and PPV. It was thought that it could be used in combination with other methods to increase diagnostic accuracy, especially for culture-negative TB cases which are difficult to diagnose.