The application value of protein biochip in the diagnosis of pulmonary tuberculosis

Objective To evaluate the application value of the joint detection of serological antibodies in the diagnosis of pulmonary tuberculosis through protein biochip detective system. Methods From March to May 2011, a retrospective analysis of tuberculosis serological antibodies was carried out in 52 patients with pulmonary tuberculosis and 33 patients without tuberculosis. The judgment standard of protein biochip as follow: one of the 5 antibodies (CFP10, LAM, ESAT-6, 38 KD and 16KD) was positive was considered positive; all of the 5 antibodies were negative was considered negative. Results The positive rates of CFP-10, LAM, ESAT-6, 38 KD and 16KD in sputum positive or negative pulmonary tuberculosis groups were 10%, 60.0%, 10%, 10%, 20% and 9.3%, 46.9%, 9.3%, 15.6%, 9.3%, respectively. The combined positive rates of the 5 tuberculosis antibodies in tuberculosis and non-tuberculosis groups were 71.2% and 15.1%, respectively (χ2 = 22.5, P = 0.00). In tuberculosis group, the positive rates of the 5 tuberculosis antibodies in sputum positive and negative patients were 85.0% and 62.5%, respectively (χ2 = 3.03, P = 0.081). As compared with the positive rate of LAM which gained the highest positive rate in the same group, the combined positive rate was improved by 25% in sputum positive group, and by 15.6% in sputum negative group. The specificity, sensitivity, accuracy, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio of the 5 antibodies in tuberculosis group were 84.8%, 71.2%, 74.3%, 87.5%, 62.2%, 4.6, and 0.339, respectively. Conclusion Detecting serological antibodies by protein biochip is a quick and convenient method with high sensitivity, accuracy and positive predictive value in assistant diagnosis of pulmonary tuberculosis.