ABSTRACT
Background: Tuberculosis [TB] is a serious infectious disease especially among patient with low immunity as chronic liver disease and long term treatment should be started early
Purpose: Rapid, reliable, simple and cost effective method for detection of Mycobacterium tuberculosis complex [MTBC] would be highly desirable. The purpose of this study was to evaluate a FASTPlaque TB [Biotec, Laboratories Ltd., Ipswich, UK] for the diagnosis of TB
Methods: We evaluated the clinical utility of this new assay by analyzing respiratory specimens of 100 suspect TB patients, using FAST Plaque TB kit and the performance was compared the results and time of detection, sensitivity, specificity and contamination rates with, smear microscopy, and Lowenstein-Jensen [L-J] culture method
Results: Of the total 100 TB "Suspect" patients, [63%] were male, aged from 11-67 years, most of them in age group [25-34 years] [35%], 50 were smear positive and 50 were smear negative, comparison of phage assay with AFB smear, Out of the 50 smear positive cases, 37 were phage positive and 13 were phage negative; 4 of which were identified as Mycobacteria Other Than Tuberculosis [MOTT]. Amongst the 50 smear negative samples, 4 samples were positive by phage assay. The sensitivity, specificity, positive predictive value and negative predictive value of the phage assay with respect to AFB smear positivity were 82%, 100 %, 100% and 83.6 % respectively. In comparison of the results of culture positivity with phage assay, it was noted that of a total of 61 culture positive samples, 41 were phage positive and 20 were phage negative of which 8 were identified as MOTT. The sensitivity, specificity, positive predictive value and negative predictive value of phage assay with respect to growth on L-J media were 77.4%, 100%, 100% and 76.5 % respectively
Conclusions: We believe that this new low cost assay may have wide spread applicability, especially in developing countries, due to its manual format and rapid reporting of results