HSV‑2–Associated Mollaret’s Meningitis in a Patient with History of Prior Episodes: A Case Report

Mollaret meningitis is a rare, recurrent form of aseptic lymphocytic meningitis, most commonly caused by herpes simplex virus type 2 infection. The clinical presentation includes sudden, recurring attacks of headache, meningismus, and lymphocytic cerebrospinal fluid pleocytosis that resolve spontaneously. We report a case of a 45‑year‑old woman with known HSV‑2 infection and two prior episodes of presumed viral meningitis who presented with progressive bitemporal headache, photophobia, nausea, vomiting, and fever. Neurologic examination was intact, and brain CT and MRI were unremarkable. Lumbar puncture revealed an opening pressure of 42 cm H₂O. CSF analysis showed WBC 441/µL (92% lymphocytes), protein 77.2 mg/dL, glucose 72 mg/dL (serum 116 mg/dL), and negative Gram stain and culture. A multiplex meningitis PCR panel was negative; however, targeted testing detected HSV‑2 DNA in CSF, confirming the diagnosis. Empiric dexamethasone (8mg IV q6hr), ceftriaxone (2G IV q12hr), vancomycin (1G IV q12hr), and acyclovir (10mg/kg/dose IV q8hr) were initiated, and antibacterial therapy was discontinued once HSV‑2 PCR positivity was established. The patient improved with supportive care. Her headache partially improved after CSF drainage and progressively resolved over the course of the hospitalization. She remained neurologically stable without visual changes and was discharged with outpatient neurology and ophthalmology follow‑up to monitor for recurrent symptoms or signs of intracranial hypertension. This case highlights HSV‑2–associated Mollaret meningitis presenting with markedly elevated CSF opening pressure, underscoring the importance of targeted CSF PCR during symptomatic episodes and the need for structured follow‑up, given the risk of recurrence and the potential for intracranial hypertension.