EVALUATION OF AMPLICOR PCR ASSAY FOR DIRE CT-DETECTION OF MYCOBACTERIUM-TUBERCULOSIS IN SMEAR-NEGATIVE SPECIMENS

The reliability of the Roche Amplicor Mycobacterium tuberculosis test (Amplicor MTB) was evaluated by testing smear-negative specimens from patients with clinical and radiological characteristics of tuberculosi s. A total of 364 clinical samples including biopsies and fluids from 153 patients was tested using the Amplicor MTB and the results were co mpared with those of culture. After discrepancy resolution and patient s chart review, sensibility, specificity, positive predictive value an d negative predictive value were 44,7 %, 99,7 %, 94,4 % and 93,9 % res pectively. Our study indicates that Amplicor MTB, despite its low sens ibility and for its high specificity can bring a valuable complement f or improving the laboratory diagnosis of tuberculosis.