Application of ELISA with antigenic glycolipids in early diagnosis of pulmonary tuberculosis.

Antibodies against M. tuberculosis antigenic glycolipids were determined by enzyme-linked immunosorbent assay (ELISA) in 80 sera from patients suspected of pulmonary tuberculosis, with suggestive clinical signs and radiological abnormalities, but smears negative. The test was also performed on 68 control sera from patients with bacteriologically confirmed pulmonary tuberculosis, in different stages of disease. We obtained the test sensitivity of 89.5% for the confirmed tuberculosis patient sera. Low levels of specific antibodies and the sensitivity of 75% were found when using ELISA in smears negative patients at the onset of clinical tuberculosis. The experimental results showed that ELISA could be used as a supporting test in early diagnosis of pulmonary tuberculosis.

Clinical usefulness of rapid serodiagnosis in pulmonary tuberculosis by ELISA with glycolipidic antigens extracted from Mycobacterium tuberculosis and with whole BCG suspension.

Antibodies against Mycobacterium tuberculosis glycolipids and whole BCG suspension were determined by ELISA on 58 sera from hospitalized patients with presumptive pulmonary tuberculosis and on 127 sera from control subjects. The experimental results demonstrated that the glycolipids are more adequate to be used as antigens than whole BCG suspension, as high sensitivity of the test was obtained. By using only one antigen, ELISA becomes more efficient in rapid diagnosis. ELISA with glycolipidic antigens should be used as a supporting test for direct smear examination in the diagnosis of pulmonary tuberculosis, especially in cases when repeated bacterial methods failed to prove the presence of M. tuberculosis.