Surgical Third Nerve Palsy as a Rare Presentation of Tuberculous Meningitis: Early Clinical Judgement and Advanced Imaging

A 22-year-old man from Bangladesh presented with a subacute febrile illness, a history of frontal headache, neuropsychiatric changes, and a right third nerve palsy (ptosis and mydriasis). Neuroimaging revealed hydrocephalus and multifocal cerebral infarcts. Cerebrospinal fluid (CSF) analysis showed elevated protein with normal glucose; however, all initial microbiological assays, including GeneXpert MTB/RIF (Mycobacterium tuberculosis/rifampicin) and culture, were negative. A clinical diagnosis of tuberculous meningitis (TBM) was made based on the clinical presentation, neuroimaging progression, and epidemiological risk factors. Treatment commenced with anti-tubercular therapy and high-dose steroids. His neurological symptoms markedly improved with medical management, averting the need for neurosurgical intervention for hydrocephalus. This case underscores that TBM can present with an isolated cranial nerve deficit. Therefore, a high clinical index of suspicion is paramount, and treatment should not be delayed.