Vestibulocochlear Neuritis as a Paradoxical Reaction in an Immunocompetent Patient with Tuberculous Meningitis

A 30-year-old previously healthy man presented with fever and headache. HIV tests yielded negative results. Cerebrospinal fluid (CSF) analysis revealed pleocytosis (619/µL), elevated protein (210.3 mg/dL) and adenosine deaminase levels, and decreased glucose levels. A positive CSF culture for tuberculosis confirmed the patient had tuberculous meningitis (TBM). He was treated with methylprednisolone, isoniazid, rifampicin, pyrazinamide, and ethambutol (all highly sensitive). His compliance with medication was good. After six weeks of treatment, he was discharged in stable condition. Eight weeks after onset, he was readmitted with vertigo and right deafness. CSF examination showed worsened pleocytosis (819/µL) and protein levels (4296.1 mg/dL). Contrast-enhanced MRI revealed enhancement of meninges in the brainstem and spinal cord as well as the right vestibulocochlear nerve. No brain abscesses were observed. Based on these findings, a paradoxical reaction (PR) with vestibulocochlear neuritis following antituberculous therapy initiation was suspected. He received oral prednisolone, leading to rapid resolution of vestibulocochlear symptoms within two days. Although cranial nerve enhancement due to PR has been mentioned in the literature, specific imaging demonstrating it is scarce. This case highlights PR as a cause of cranial neuropathy in TBM and provides clear radiological evidence of direct inflammatory spread to the vestibulocochlear nerve, bridging a gap in the current literature.