Diagnosis of Tuberculous Meningitis by Using TRC4 and IS611O Primers in Bangladesh

Meningitis caused by Mycobacterium tuberculosis remains an important cause of morbidity and mortality worldwide, and presents particular challenges in terms of diagnosis and management. The prevalence of TB meningitis remains largely underestimated due to nonspecific clinical manifestation. At early stages diagnosis is largely based on microscopy and culture which are often less sensitive and time consuming. This study was aimed to evaluate the diagnostic potentials of urinary polymerase chain reaction (PCR) by using TRC4 and IS6110 primers. Further the results were also compared by culture on Lowenstein-Jensen (LJ) media and AFB smear by Zeihl-Nelson (ZN) staining. A total of 20 CSF samples were studied from clinically suspected cases of tubercular meningitis. All the samples were processed for conventional ZN staining, TB culture on LJ media and TB-PCR by IS6110 and TRC4 primers by standard protocols. Of the total 20 samples, 12 cases were diagnostically positive TB meningitis samples among which bacteriological test was positive in only 1(8.33%) cases. PCR assay detected MTb in 10(83.33%) patients by TRC4 primers and in 8 (66.67%) patients by IS6110 primers. Since some strains of MTB may lack the IS6110 element in their genomeusing TRC4 primer instead of IS6110 is superior in diagnosing tubercular meningitis by PCR assay.