TUBERCULOUS MENINGITIS

Abstract

Objective: To evaluate the role of cerebrospinal fluid (CSF) polymerase chain reaction (PCR) for Mycobacterium Tuberculosis in
rapid diagnosis of tuberculous meningitis (TBM). Study Design: Prospective observational study. Place and Duration of Study: Medical A unit
Hayat Abad Medical complex Peshawar from 1st September 2010 to 30th August 2011. Methodology: A total of 20 Patients having fever,
constitutional symptoms (malaise, vague ill health, headache, vomiting), nuchal rigidity with altered mental and behavior changes were
suspected as TBM and hence included in the study. Patients were divided into two groups based on direct and indirect evidence of tuberculosis
in central nervous system (CNS) of patients. Group1: Patients having direct evidence of mycobacterial infection in CNS as Acid Fast Bacilli
smear positive in CSF. Group 2: Patients with indirect evidence of TB in CNS in form of typical CSF findings of TBM, positive sputum smear for
Acid fast bacilli (AFB) or computed tomographic (CT) Scan brain findings suggestive of TBM or evidence of TB in x-ray chest or family History of
tuberculosis and/or history of contact with TB patients or positive Mantoux Test or evidence of TB elsewhere in the body. Results: Out of total 20
patients, 3 (15%) belonged to Group 1 having direct evidence of TBM the remaining 17 (85%) patients belonged to Group 2. Female patients
were 60% while 40% patients were male. Mean age was 35.8 years. All patients had fever and headache. Productive cough was present in 40%
patients. Thirty five percent had lost weight. Contact with TB patients was revealed in 35% patients. Signs of meningeal irritation were elicited in
90% patients. Cranial nerve palsies were seen in 25% patients, 10% had hemiparesis while 35% had impairment of consciousness. X-ray chest
was normal in 65%.Computed tomographic scan was showing meningeal enhancement in 30% patients, hydrocephalus in 15% patients,
meningeal enhancement plus hydrocephalus in 55% patients and infarct in 15% patients. Three patients were enrolled in group 1 and all had
PCR positive for mycobacterium tuberculosis. Of 17 patient in group 2, 64% patients had positive CSF PCR. Conclusions: Tuberculous
meningitis is an important serious extrapulmonary complication of TB, related with high mortality and morbidity. The prompt and accurate
diagnosis of TBM is a daunting challenge. CSF PCR for Mycobacterium tuberculosis is an excellent test for rapid diagnosis of TBM.