Case Presentation: A 35 year-old undomiciled male with a history of epilepsy and recurrent aseptic meningitis was brought in to the emergency department after being found unresponsive. Initial vital signs were notable for temperature of 102˚F. He was intubated in the emergency department and a lumbar puncture was done consistent with a bacterial meningitis (WBC 1460, neutrophils 86%, protein 621, glucose <4). Empiric vancomycin, ceftriaxone, and dexamethasone were initiated. His mental status improved and he was extubated on hospital day (HD) 2. On HD 3, blood cultures returned growing Streptococcus Pneumoniae and his antibiotics were narrowed to ceftriaxone. His cerebral spinal fluid (CSF) polymerase chain reaction (PCR) also returned positive for herpes simplex virus 2 (HSV2), so he was started on acyclovir. He continued to improve on this therapy and he was subsequently discharged after he completed a ten-day course of intravenous ceftriaxone. He was discharged with oral valacyclovir to complete a fourteen-day total course of this antiviral medication.
Discussion: Benign recurrent lymphocytic meningitis (RLM), also known as Mollaret’s meningitis, is a rare disease that may be under-diagnosed. It is characterized by recurrent episodes of aseptic meningitis that is most often caused by HSV2. Typically, CSF studies show a cell count that is predominantly lymphocytes; however, the patient in this case presented with a concurrent bacterial meningitis which masked both the clinical and laboratory features of RLM. Though many of the patient’s presenting symptoms were more likely due to bacterial meningitis, treating what was likely RLM secondary to HSV2 reactivation may have led to faster recovery and fewer recurrences.
Conclusions: In a patient that presents critically ill with meningitis, it is prudent to send HSV2 PCR from the CSF sample and empirically treat with antivirals in addition to antibiotics until HSV2 PCR returns negative. Furthermore, we postulate that the invasion of the meninges by HSV2 in Mollaret’s meningitis may predispose patients to acute bacterial meningitis. Currently there is a paucity of literature regarding viral and bacterial meningitis coinfection, however we suspect this entity is likely underdiagnosed. Having a lower threshold for sending HSV2 PCR from the CSF in cases of confirmed bacterial meningitis may lead to an increase in the detection rate of concurrent viral meningitis.