Systemic and deep-seated infections caused by Arcanobacterium haemolyticum.

Arcanobacterium haemolyticum has been implicated mainly in non-streptococcal pharyngitis and wound infections. Rarely, it has been reported to cause systemic infection, often in combination with other pathogens. Two cases of systemic and deep-seated infections caused by Arcanobacterium haemolyticum are reported, and the literature is reviewed. Sixteen cases of bacteremia and seven cases of non-bacteremic deep-seated have been published previously. Eight of the bacteremic and two of the non-bacteremic cases occurred in younger, apparently healthy immunocompetent patients. Six patients had infections of the central nervous system. The optimal treatment of infections caused by Arcanobacterium haemolyticum is not known. Although in vitro susceptibility tests have demonstrated tolerance of Arcanobacterium haemolyticum to penicillin, penicillins with or without aminoglycosides have been the most widely used antibiotics, in most cases with success.