Abstract: Tuberculosis still constitutes a major health problem through the world in spite of major advances in
diagnosis, treatment and prevention. Annually, 8 million people become ill with tuberculosis, and 2 million people
die from the disease worldwide. Several ELISA tests 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. The present study aimed to measure the diagnostic value of 16-kDa and 38-kDa mycobacterial
antigens in patients who were diagnosed with Tuberculosis by clinical and, or bacteriological findings. This study
was carried out in Chest Department of Benha University Hospital on 5 groups which were (40) patients smear
positive pulmonary tuberculosis, (20 ) patients smear negative pulmonary tuberculosis, (20) patients inactive
pulmonary tuberculosis and control group of (20 ) patients with disease other than tuberculosis. Eg. COPD
Broncheactasis, and (20) normal healthy subjects. Medical history, clinical examinations, complete blood picture,
ESR, Liver Function Tests, Kidney Function Tests, Fasting Blood Sugar, Tuberculine Skin Test by Montoux
Method, sputum for Acid Fast Bacilli by Z.N. stain, pathozyme-TB Complex plus commercial ELISA kit for
measuring Immunoglobulin G against 38-kDa and 16-kDa recombinant antigens of all tested groups of TB and
control groups. Our findings demonstrated that specificity, sensitivity, positive predictive value, negative predictive
value for smear positive group were 97%, 75%, 98.4% and 30% respectively. And for smear negative pulmonary
tuberculosis were 95%, 65.2%, 95%, 81% and 80% as regarding specificity, sensitivity, positive predictive value,
negative predictive value respectively. Antibodies were detected at above cut-off level in (2) 10% out of (20)
subjects with inactive TB. In conclusion, the ELISA Test has a very good specificity and an acceptable sensitivity
and positive predictive value for diagnosis and follow-up of Pulmonary Tuberculosis. Recommendation: It is
recommended that it could be used in combination with other method to increase the diagnostic accuracy especially
for smear negative Tuberculosis cases. |
