Diagnostic and prognostic significance of chest radiographs in adult tuberculous meningitis: A retrospective study

Abstract

Background: Tuberculous meningitis (TBM) is the most severe form of extra-pulmonary TB, carrying significant morbidity and mortality. Our study examined the diagnostic utility and prognostic value of abnormal chest X-rays (CXRs), alongside other clinical, laboratory and neuroimaging features in adult TBM. Methodology: This retrospective study used the Lancet consensus criteria to include all patients diagnosed with TBM at a tertiary referral centre from 2010-2020. Clinical, laboratory and radiological findings on admission were identified. The presence of tuberculomas, enhancement pattern, hydrocephalus, and infarction was assessed using brain imaging. Findings were compared to the functional outcome on the modified Rankin scale (mRS) at 90 days (good: mRS 0-2, poor: mRS 3-6). Correlation with functional outcomes was determined using logistic regression. Cases without imaging were excluded.

Results: This study included 31 adults diagnosed with TBM (median age: 37 years, range: 18-67 years). Abnormal CXRs were seen in 51.61% of patients. Poor functional outcomes were observed in 51.61% of patients and were independently associated with abnormal CXRs (aOR 20.07, 95% CI 1.63-247.60), the absence of Bacillus Calmette-Guérin (BCG) inoculation (adjusted odds ratio (aOR) 7.89, 95% CI 1.01-61.55) and lethargy (aOR 15.89, 95% CI 1.28-196.86). We found significant differences between good and poor outcomes in patients with cerebrospinal fluid (CSF) polymorphs (median: 6% vs median: 43%), CSF lymphocytes (median: 88% vs median: 12%) and cerebral infarction (0% vs 100%).

Conclusion: Abnormal chest radiographs help guide the diagnosis of TBM while awaiting definitive CSF results. They also are independently associated with poor functional outcomes.