The Value Of Serum Neopterin,adenosinedeaminase Level And PPD In Diagnosing Active Pulmonary Tuberculosis

Objective: To investigate the sensitivity and specificity of serum neopterin (NP), adenosinedeaminase level and tuberculin purified protein derivative skin test(PPD) in diagnosing active pulmonary tuberculosis. Methods: Untreated patients admitted in Xinjiang Chest Hospital with pulmonary tuberculosis were consecutively enrolled from April 2009 to May 2010. Serum neopterin level was detected by enzyme linked immunosorbent assay (ELISA) in the next morning of admission. Purified protein derivative test (PPD) was concurrently performed, ADA level was tested by kinetic method. Results: 58 patients with active pulmonary tuberculosis and 18 cases with stable pulmonary tuberculosis were recruited and 32 healthy volunteers were served as control in this study. NP and ADA values of active pulmonary tuberculosis group was significantly higher than the stability of the tuberculosis group and the control group,while there was no significant difference between the stability of the tuberculosis group and the control group.NP value of fiber cavitary tuberculosis group was significantly higher than that of pulmonary tuberculosis group and hematogenous disseminated pulmonary tuberculosis group, the value of serum ADA of hematogenous disseminated pulmonary tuberculosis group was higher than that of fiber cavitary tuberculosis group and pulmonary tuberculosis group. ROC(receiver operating curve)curve analysis showed that 36.73 nmol/L was the critical value, the area under the curve of the serum NP of active pulmonary tuberculosis was 0.951, the sensitivity and specificity were 83% and 92%. Positive likelihood ratio was 10.34,the positive likelihood ratio of NP in all subtypes was high, but in the pulmonary tuberculosis group, ratio of PPD(12.00)was the highest, the sensitivity of ADA in fiber cavitary tuberculosis group ,pulmonary tuberculosis group and hematogenous disseminated pulmonary tuberculosis group were 86%,50% and 83% and the specificity were 84%, the positive likelihood of them were 5.38,3.13,5.19 respectively. Conclusion: The value of serum NP as an important indicator of diagnosising active tuberculosis. The value of serum ADA maybe important on diagnosing fiber cavitary tuberculosis group and hematogenous pulmonary tuberculosis.PPD is still a more important secondary diagnosis for pulmonary tuberculosis.