A Dilemma in the Diagnosis of Group A Streptococcus (GAS) Meningitis Versus Drug-Induced Aseptic Meningitis: A Case Report

Group A <i>Streptococcus</i> (GAS), also called <i>Streptococcus pyogenes</i>, is a rare cause of adult meningitis. In recent years, many outbreaks of invasive <i>S. pyogenes</i> infections in Europe, involving the <i>emm</i>1.0 subtype of the M1UK lineage, have led to a rising prevalence of GAS meningitis. We present a case with a diagnostic dilemma involving a 55-year-old female with otitis media, <i>S. pyogenes</i> bacteremia, and symptoms of meningitis. However, cerebrospinal fluid (CSF) tests were not completely consistent with bacterial meningitis, with normal glucose levels on CSF analysis, no organism seen on gram stain, and no growth on CSF culture. Drug-induced aseptic meningitis (DIAM) was considered, given the patient's use of ibuprofen prior to admission, and thus, non-steroidal anti-inflammatory drugs (NSAIDs) were avoided during her hospitalization. The GAS bacteremia was treated with intravenous ampicillin. She improved a few days later, but we are uncertain whether the antibiotics or the avoidance of NSAIDs resolved her meningitis symptoms. On discharge, ampicillin was switched to intravenous ceftriaxone, 2 g every 12 hours, to treat possible GAS meningitis for a four-week duration.