Periorbital and Central Nervous System Infection Due to Arcanobacterium haemolyticum: Case Report and Review of the Literature.

Arcanobacterium haemolyticum is a facultative anaerobe, catalase-negative, Gram-positive pleomorphic rod, most commonly responsible for pharyngeal infections. Invasive A. haemolyticum infections are rare and typically involve immunocompromised patients; however, severe and invasive infections in immunocompetent patients have also been reported. Here we describe a case of sinusitis complicated by periorbital cellulitis, subdural empyema and cerebritis due to A. haemolyticum in an immunocompetent patient. The patient was initially treated with daptomycin + piperacillin/tazobactam and subsequently with linezolid + meropenem and required multiple surgical interventions to attain source control. Although uncommon, A. haemolyticum should be considered as a causative agent of severe infections complicating pharyngitis or sinusitis that may result from local extension or haematogenous spread, even in an immunocompetent host. We also present a literature review on central nervous system involvement by A. haemolyticum infection.