The diagnostic values of serum tuberculosis antibody detection combined with PPD skin test

Aim To evaluate the value of 3 tuberculosis antibody kits combined with PPD skin test for the diagnosis of tuberculosis.Methods Sera from 100 pulmonary tuberculosis,48 extra pulmonary tuberculosis and 50 controls were tested at the same time with 3 TB antibody detection kits tuberculin skin(PPD) test were carried out.Results The positive rate 3 of Kit in detection of pulmonary tuberculosis and extra pulmonary tuberculosis were 90.00% and 83.33% respectively.The specificity was 92%.The specificities of kit 1 and kit 2 were both above 95%,but their sensitivities were below 50%.If any one of the test result of four detection method was positive then it was regarded as positive,and the specificity of two or three serological tests were over 90% and the specificity of any serologic test combined with PPD test was lower than 50%.No positive result was recorded unless all four test results were positive for tuberculosis.The positive rate and the specificity of kits combined with PPD test in detection of extra pulmonary tuberculosis was above 80% and 96%,while the sensitivity and specificity of other detection methods were below 50% and 100%.Conclusion The positive rate,sensitivity and specificity of the four testing methods in detection of tuberculosis can be improved if combined with each other.