rpoB nested PCR and sequencing for the early diagnosis of tuberculous meningitis and rifampicin resistance

Abstract

Setting: The prognosis of tuberculous meningitis (TBM) is linked to early diagnosis and prescription of adequate treatment.

Objective: To evaluate the efficacy of the rpoB nested polymerase chain reaction (PCR) and sequencing assay to detect and identify Mycobacterium tuberculosis complex (MTC) strains and strains resistant to rifampicin (RMP) in cerebrospinal fluid specimens (CSF) from patients with highly suspected TBM.

Design: Retrospective blinded hospital-based study.

Results: rpoB nested PCR and sequencing assay detected MTC in 31/36 CSF specimens from 16 patients with clinically suspected TBM. All of the control CSF specimens from 25 patients with non-TBM showed negative results. One of the 16 patients had a mutation at codon C526G as compared to the rpoB sequences in GenBank. This corresponds to a diagnostic sensitivity of 86% (95%CI 71-95) and a specificity of 100% (95%CI 86-100).

Conclusion: Our results suggest that rpoB nested PCR and sequencing assay can detect MTC and simultaneously determine its RMP susceptibility in CSF from patients with highly suspected TBM.