Tuberculosis is an enormous tool of morbidity and mortality. The vast majority of tuberculosis patients live in developing countries, where the diagnosis of tuberculosis relies on the identification of acid-fast bacilli on unprocessed sputum smears using conventional light microscopy. Microscopy has high specificity in tuberculosis-endemic countries, but modest sensitivity -which varies among laboratories (range 20% to 80%).. Thus, the development of rapid and accurate new diagnostic tools is imperative. Immune-based tests are potentially suitable for use in low-income countries as some test formats can be performed at the point of care .In the present study, the diagnostic value of 16-kDa and 38- kDa mycobacterial antigens was investigated in patients who were diagnosed as open pulmonary tuberculosis. The humoral immune response was analysed in a group of 60 TB patients, and in control group consisting of 15 healthy volunteers and 15 subjects with pulmonary diseases other than TB. The sensitivity, specifity, positive predictive value and negative predictive value of the test were determined at 45%, 93.3%, 93.1% and 45.9%, respectively. In conclusion, the ELISA test has a very good specifity and an acceptable sensitivity and positive predictive value. It is thought that it could be used in combination with other methods to increase diagnostic accuracy, especially for culture-negative tuberculosis cases, which are difficult to diagnose.
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