Due to the time-dependent nature of thrombolysis in acute ischemic stroke, AHA guidelines recommended administering intravenous tissue plasminogen activator (IVtPA) to patients even when stroke mimics are suspected to avoid delaying eligible acute ischemic treatment. In large series of IVtPA, nearly one-third of patients are ultimately diagnosed with a stroke mimic. Aseptic meningitis is the final diagnosis in approximately 1%.

A 41 year old male with a medical history of ocular migraines developed sudden onset aphasia and confusion associated with right sided numbness. He had recently travelled to Montana 2 weeks prior and was ill during the trip (headaches, malaise). On presentation, CT brain was negative. Initial National Institutes of Health Stroke Scale (NIHSS) was 5. He was given IVtPA at 1 hour 46 minutes after symptom onset. CT angiogram head/neck was negative. MRI Brain diffusion weighted imaging was negative. Temperature was 100 F without leukocytosis. He was empirically started on antibiotics. Given normal fibrinogen, lumbar puncture (LP) was performed the next day (at 20 hours post IVtPA). Cerebrospinal fluid (CSF) showed WBC 120/uL with lymphocytic 88%, protein 98 mg/dL, and glucose 82 mg/dL. All CSF testing was negative including BioFire panel, Rickettsia battery, West nile virus, Ehrlichia PCR, Lyme Ab, and CSF cultures. Infectious disease consultants recommended stopping broad coverage, and he completed a 14 day course of doxycycline. His confusion resolved over 2 days and he returned to baseline. Discharge NIHSS was 0. Final diagnosis was aseptic viral meningitis. He remained asymptomatic at 1 month follow-up.

Clinicians should be aware of unusual stroke mimics, such as aseptic meningitis, that may receive IVtPA inadvertently. The use of IVtPA in stroke mimics is considered safe, although in the case of meningitis, may delay the performance of LP due to the 24 hour IVtPA window protocol.