Polymerase Chain Reaction as a Rapid Tool for the Diagnosis of Pulmonary Tuberculosis

Abstract

The study aimed to use PCR, as a rapid tool for the diagnosis of pulmonary tuberculosis from sputum samples among clinically suspected patients in Khartoum state Sputum samples were collected from patients attending Abu Anga Hospital, Alsha’ab Teaching Hospital and Tuberculosis Reference Laboratory. Patients were consented and informed. From 171 patients 30 (17.5%) has a history of previous infection with TB while 141 (82.5%) were consider as new cases. Direct smear result showed that 37 (21.6%) Smear were positive while 134 (78.4) showed negative. All sputum samples were inoculated in LJ media, 40 (23.4%) showed MTC-like colonies, 10 (5.8%) were considered rapidly growing mycobacteria, 2(1.2%) showed contamination and 119 (69.6%) no growth. The recover MTC-like colonies were identified by conventional methods. DNA was extracted from all sputum samples using Isopropanol method. Then they were subjected to PCR where 142 (83%) samples showed IS 6110 amplicons of 123 bp in size as indicated by the DNA marker. 29 (17%) samples were PCR negative. These results revealed clearly the importance, feasibility and sensitivity of the PCR as a rapid diagnostic tool to detect M. tuberculosis from direct sputum sample.