The elusive diagnosis: recurrent benign lymphocytic meningitis.

BACKGROUND: Recurrent benign lymphocytic meningitis (RBLM) or Mollaretmeningitis is a rare disease with a prevalence of 1-2.2/100,000 population. It is characterized by recurrent episodes of aseptic meningitis. The diagnosis is made via history fitting Bruyn's criteria, and confirmatory detection of HSV-2 in cerebrospinal fluid (CSF) via polymerase chain reaction (PCR). CASE: A 59-year-old female with a past medical history (PMH) of rheumatoid arthritis in remission and 11 prior episodes of aseptic meningitis presented with sudden and severe headache, photophobia, nausea, vomiting, and meningismus without focal findings. CSF analysis revealed aseptic meningitis with Herpes simplex 2 virus (HSV-2) present by PCR. CONCLUSION: RBLM remains a rare and elusive diagnosis but PCR technology has made it easier to diagnose. We present a 59-year-old female with classic features of RBLM, now suffering a 12th episode of aseptic meningitis. Heightened awareness of RBLM among clinicians may allow for an earlier diagnosis, reduced use of unnecessary antibiotics, shortened hospitalizations, and lower costs.