Single vs multiple pathogens in brain abscesses: Two cases with distinct aetiologies

Abstract

Brain abscesses represent life-threatening focal infections with diverse aetiologies. In the current era of escalating antimicrobial resistance, medical management is increasingly challenged and empiric regimens may be insufficient. We report two young immunocompetent male patients with brain abscesses due to distinct aetiologies: a monomicrobial subdural and epidural collection caused by Streptococcus constellatus and a polymicrobial post-traumatic orbitofrontal abscess associated with Enterococcus faecalis and Escherichia coli. Both patients underwent urgent surgical drainage combined with broad-spectrum intravenous antibiotics, later tailored to culture results. The first case illustrates the risk of suboptimal oral therapy and poor adherence, with subsequent relapse and development of antimicrobial resistance, whereas the second case highlights infectious complications following penetrating orbito-cranial trauma. These contrasting cases emphasise the need for timely neurosurgical intervention, prolonged targeted antimicrobial therapy, and strict avoidance of unsupervised antibiotic use in the management of brain abscesses.