Comparison of Mantoux Reactivity in Smear Positive Pulmonary Tuberculosis Adults and Controls in Yenagoa, Nigeria

Background: Tuberculin skin tests (TST) are long established screening methods for tuberculosis (TB). We aimed to compare Mantoux test (a TST) in smear positive pulmonary tuberculosis adults and control subjects. From January to December 2015, 131 patients with smear positive pulmonary (mean age 36.9 years) were given the Mantoux test. The results of the test group were compared with those of 121 control subjects (mean age 33.5 years).

Methods: Mantoux test results of all the 131 patients with smear positive pulmonary tuberculosis, aged above 15 years without HIV were collated and then analysed. These results were compared with results from 121 control subjects who were attending the chest clinic for other conditions, who were also smear negative with normal chest radiograph.

Results: Mean Mantoux reaction (mean±SD) for the test group was 9.31+10.6 mm while the mean reaction in the control group was 8.22±6.4 mm giving a p-value of 0.80 (Z-test). Thus there was no statistically significant difference between the test group and the control.

Conclusion: We conclude that the Mantoux test has limited usefulness as a screening or diagnostic tool.