Spectrum of Presentation, Diagnosis, and Clinical Outcome of Central Nervous System Tuberculosis: A case series in Bangabandhu Sheikh Mujib Medical University

Abstract

Introduction: Tuberculosis (TB) is highly prevalent in Bangladesh. The affection of the central nervous system(CNS) is one of the most dangerous manifestations of extrapulmonary tuberculosis. This may take the form of either tubercular meningitis (TBM), tuberculoma, or spinal arachnoiditis. CNS tuberculosis (CNS-TB) carries high morbidity and mortality among all forms of TB. The diagnosis is difficult and often delayed due to the varied and non-specific presentation. Aside from clinical indicators, cerebrospinal fluid (CSF) diagnostic indicators include mononuclear pleocytosis, low sugar levels, and high protein concentrations. It is possible to confirm Mycobacterium tuberculosis in CSF using staining, culture methods, and molecular analysis, but it is difficult. Advanced radiological imaging techniques can often be very helpful in making presumptive diagnoses, but they do not always yield confirm diagnoses. Aim: In our case series, we aimed to highlight the spectrum of presentation of CNS tuberculosis, diagnostic challenges, and initial response to anti-TB drugs. Material and Methods: We report a case series of six patients with CNS tuberculosis admitted to the neurology department between 2022 and 2023. Four of them were prospectively reviewed and two retrospectively. Data on presentation, diagnostic workup, and treatment were analyzed. Result: We presented six cases of CNS TB from 2022 to 2023. Four cases among six had only TBM, two cases had concomitant intracranial tuberculoma and two cases had tuberculosis in the extracranial site. The most common presentation were fever, altered consciousness level, and constitutional symptoms. CSF study was done and revealed increased total protein in all six cases, lymphocytic pleocytosis in 66.67% of cases, a low sugar level in 50% of cases, and raised ADA level in 66.67% of cases. MTB was detected in a polymerase chain reaction (PCR) in one case and was none positive for AFB stain and culture. MRI with contrast showed meningeal enhancement in all six cases, hydrocephalus in 66.67% of cases, and infarction and tuberculoma in 33.33 % of cases. Brain biopsy for histopathological confirmation was not done. All of them had an anti-tubercular therapy and reported good clinical responses at 21-day-follow up. Conclusion: CNS TB should be diagnosed primarily based on compatible clinical features, morphological findings on brain MRI, and CSF findings. In Bangladesh, CNS TB should always be considered an important differential diagnosis in patients with prolonged fever and headache, as well as altered consciousness level, and treatment should be initiated immediately on the basis of strong clinical suspicion, rather than waiting for laboratory confirmation.