Diagnosis of tuberculosis meningitis by using Trc4 and Is6110 primers in Bangladesh

Abstract

Tuberculosis (TB) is a highly prevalent global human infection caused by Mycobacterium tuberculosis (MTB). One-third of the world’s population is infected with latent TB. Tuberculous meningitis (TBM) can occur as the sole manifestation of TB or concurrent with pulmonary or other extra pulmonary sites of infection.1,2 Tuberculosis (TB) is the major cause of death worldwide and is due to a single pathogen.3 TB meningitis in particular owes their existence to unsuspected, undiagnosed, or incompletely treated in the community. Mortality due to TB occurs mainly due to the neural form of TB, namely, TB meningitis. Delay in diagnosis and so in the start of effective treatment results in poor prognosis and sequalae in up to 25% of cases.4 Prompt diagnosis is critical for initiating appropriate therapy and facilitating measures to prevent dissemination of this highly contagious disease. The prevalence of TB meningitis remains largely underestimated because clinical manifestations are nonspecific in early stages of the disease and bacteriologic confirmation is available only for a small proportion of patients. Also, clinical diagnosis of TB meningitis is difficult due to its varied clinical presentations. Further, routinely used tests employed for clinical diagnosis of TB are inadequate to detect extrapulmonary forms of TB like TB meningitis. PCR is currently the most sensitive and rapid method to detect extra pulmonary Mycobacterium tuberculosis.5-7 We used as a new target TRC4, which was cloned and characterized previously in our laboratory (10). TRC4 is a conserved repetitive element with specificity for M. tuberculosis complex. The aim of this paper was to compare the efficiency of a PCR with a target chosen from this cloned fragment with that of a PCR with the widely used IS6110sequence in detecting M. tuberculosis in cerebrospinal fluid (CSF) samples from patients with meningitis. Materials and methods