Glutaraldehyde test for rapid diagnosis of pulmonary tuberculosis

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 +/- 138.3; 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 85.5%, 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.