Serodiagnosis of extrapulmonary mycobacteriosis by ELISA using 30,000 Da and PPD antigens

Serological diagnosis of 31 cases of extrapulmonary Mycobacteriosis [21 meningitis, 8 urinary, 10 bone and joint and one endometritis cases] 8 controls of other extrapulmonary cases and 16 healthy controls. ELISA test was used to detect serum Ig[G] and Ig[M] antibodies to 30, 000 Dalton [Da] and purified protein derivative [PPD] antigens of M. tuberculosis. The results were statistically analysed by accuracy index, sensitivity, specificity, positive and negative predictive values. Ig[G] detection using 30, 000 Da gave a higher sensitivity than PPD [66.6% and 52% respectively], while both antigens gave 100% specificity. On the other hand, the dual antigen gave a sensitivity of 85.7% and specificity 100%. A higher statistical significant difference was observed between cases and controls [P<0.005]. Detection of specific Ig[M] antibodies revealed no appreciable diagnostic value. It can be concluded from this study that the use of the dual antigen for detection of Ig[G] was reliable for the diagnosis of mycobacterial infection, however, it can't differentiate between Mycobacterial tuberculosis and other mycobacteria

Isolation and identification of mycobacteria from pulmonary and extrapulmonary cases

Samples from 71 clinically suspected cases of pulmonary tuberculosis and 55 clinically suspected cases of extrapulmonary tuberculosis as well as 20 patients with pulmonary diseases other than tuberculosis as pulmonary controls, 12 controls for extrapulmonary cases, and 16 healthy controls for pulmonary and extrapulmonary cases were examined bacteriologically. Among the 71 suspected pulmonary tuberculosis, 30 cases had positive mycobacterial culture. The Z.N. smears were positive in 76.6% of them and all isolates were identified as M. tuberculosis. Suspected extrapulmonary tuberculous cases revealed 12 meningitis, 8 urinary and 1 endometritis were positive bacteriologically for mycobacteria

Serodiagnosis of active pulmonary tuberculosis by Elisa using 30,000 DA and PPD antigens

Measurement of serum IgG and IgM antibodies to 30,000 Dalton [Da] and purified protein derivative [PPD] antigens of M. tuberculosis by enzyme-linked immunosorbent assay [ELISA] was evaluated as a serodiagnostic test for active pulmonary tuberculosis. The results of the two antigen preparations were integrated as dual antigen ELISA approach. Parameters of measurement of IgG were accuracy index, sensitivity, specificity, positive and negative predictive values, which were in case of using 30,000 Da antigen 81.8, 60, 100, 100 and 75%, respectively; while on using PPD antigen were 84.8, 73.3, 94.4, 91.6 and 80.95%, respectively. By dual antigen approach these parameters were 87.87, 80, 94.4, 92.3 and 85%, respectively. On the other h and, IgM measurement by 30,000 Da antigen revealed the figures 56, 20, 86, 54.5 and 56.4%, respectively, while by using PPD antigen, were 60.6, 13.3, 100, 100 and 58%, respectively. The dual antigen values were 56, 20, 86, 54.5 and 56.4%, respectively. The IgG detection by ELISA can be considered a reliable diagnostic test, while IgM detection was unreliable. The dual antigen ELISA approach increased the sensitivity of the test