Subdural empyema in a 14-year-old female initially diagnosed as meningitis: a case report of a rare Streptococcus constellatus infection.

BACKGROUND: Subdural empyema (SDE) is an uncommon, potentially life-threatening intracranial infection that can present with meningitis-like features, causing a diagnostic challenge. Streptococcus constellatus, a member of the Streptococcus anginosus group, is an unusual cause of central nervous system infections in adolescents, but is well known for its propensity to form abscesses.

CASE PRESENTATION: We report a previously healthy 14-year-old female who presented with acute severe headache, neck stiffness, photophobia, and vomiting following an upper respiratory illness with foul-smelling nasal discharge. Laboratory testing showed marked systemic inflammation (C-reactive protein >320 mg/L) and neutrophilia. Head CT demonstrated a right-sided 6-mm subdural collection with midline shift; magnetic resonance imaging confirmed a SDE with leptomeningeal enhancement and restricted diffusion. She underwent endoscopic sinus surgery and bilateral craniotomy for evacuation of the empyema with intracranial pressure monitoring; intraoperative cultures from the purulent collection grew S. constellatus. Management included targeted intravenous antibiotics and early neurorehabilitation. The patient exhibited steady improvement, as evidenced by clinical and laboratory findings.

CONCLUSION: This case highlights that SDE can mimic meningitis in adolescents and underscores the importance of suspecting SDE in the presence of focal neurological deficits in addition to meningeal signs. Early neuroimaging, prompt combined surgical source control (including sinus drainage), and culture-directed antimicrobial therapy are essential for favorable outcomes. Clinicians should consider S. constellatus as a possible pathogen in sinus-associated intracranial empyema.