Abstract

OBJECTIVE: To determine the diagnostic value of blood glutaraldehyde gelification time in pulmonary tuberculosis (PTB). DESIGN: We analysed the blood gelification time using 2.5 glutaraldehyde in 83 PTB patients, 46 patients with non-tuberculosis pulmonary disease and 43 healthy subjects. RESULTS: The mean gelification time of PTB patients (556.9 +/- 122.4) is significantly less than non-tuberculosis pulmonary disease (708.0 +/- 100.5) and healthy subjects (821.2 +/- 1.38.3; P < 0.0001). The optimum cut-off point was 615 seconds by receiver operating characteristic curve analysis. The sensitivity, specificity, positive predictive value and negative predictive value were respectively 85.5, 89.1, 93.4 and 77.3 in distinguishing TB from non-PTB patients; and respectively 8S.5, 93.3, 92.2 and 87.4 in distinguishing PTB patients from controls (non-PTB patients and healthy subjects). CONCLUSION: Because many centres lack sputum culture capacity and sophisticated radiology facilities, the glutaraldehyde test in conjunction with other conventional methods of diagnosis (sputum smear for acid-fast bacilli and frontal chest X-ray) could be a rapid, easy, cost-effective and reliable test for the diagnosis of PTB.