Evaluation of the MycoDot test for the diagnosis of tuberculosis in HIV seropositive and seronegative patients.

SETTING

Patients were recruited from Siriraj, Bamrasnaradura, and Central Chest Hospitals, the three major hospitals responsible for tuberculosis patients in Bangkok, Thailand, and vicinity.

OBJECTIVE

To evaluate a new rapid serologic test, the MycoDot test, for diagnosis of tuberculosis (TB).

DESIGN

The study was conducted as a cross-sectional survey. A total of 594 patients were tested with the MycoDot test. This included 142 human immunodeficiency virus (HIV) seropositive patients with active TB, 144 HIV seronegative patients with active TB, 153 HIV seropositive controls, and 155 HIV seronegative controls.

RESULTS

The sensitivity of the MycoDot test for detection of TB was 40.1% in HIV seropositive patients, compared with 63.2% in HIV seronegative patients (P < 0.001). If only patients with laboratory proven TB were evaluated, the sensitivity was 40.6% in seropositive and in 70.8% seronegative patients. The sensitivity of the MycoDot test was similar in TB patients with pulmonary and extra-pulmonary disease. The sensitivity of the test in patients with CD4 counts > or = 200 cells/mm3 was significantly higher than in those with CD4 counts < 200 cells/mm3. The specificity of the test was 97.4%, and was identical in HIV seropositive and seronegative individuals.

CONCLUSION

The MycoDot test had a higher sensitivity for the diagnosis of TB among HIV seronegative than HIV seropositive patients. Although the MycoDot test has a less than optimal sensitivity, the test specificity approaches 100%. It may be useful in patients with suspected TB and negative smears and in extra-pulmonary TB.