Primary Central nervous system vasculitis mimicking Tuberculous Meningitis: A case report

Background Primary central nervous system vasculitis (PCNSV) is a rare disease characterized by inflammatory infiltration of blood vessels in the central nervous system (CNS). Owing to the lack of specificity in its clinical features and imaging examinations, it is highly prone to being missed or misdiagnosed. Case presentation A 58-year-old female from South China was admitted with headache in March 2025. Brain MRI suggested possible intracranial inflammation, and cerebrospinal fluid (CSF) examination revealed increased cell counts, decreased glucose and chloride levels, and elevated protein levels. CNS viral infection was considered, and empirical antiviral and anti-inflammatory effects with penciclovir and dexamethasone yielded no improvement. Then, diagnostic anti-tuberculosis (TB) treatment was given, there was no improvement in symptoms. Weeks later, the patient's condition worsened, with persistent headache accompanied by nausea, vomiting, cognitive dysfunction and memory decline. Even after intensified steroid therapy, the response was still poor. A subsequent craniotomy biopsy confirmed central nervous system vasculitis. Conclusion This case illustrates that PCNSV can present with symptoms such as headaches and abnormal cerebrospinal fluid indicators, which closely resemble CNS infections. For patients with poor response to empirical antibiotic therapy, early biopsy can help improve diagnostic accuracy and prognosis.