Arcanobacterium hemolyticum infections are a common cause of pharyngitis and 
rash in the 10- to 30-year-old age group. Despite its prevalence, many emergency 
and primary care physicians may not be aware of the pathogenic potential of this 
organism. We present a case that illustrates the distinctive clinical spectrum 
of A. hemolyticum infections that may be confused with drug allergy, group A 
streptococcal scarlet fever, diphtheria, and even toxic shock syndrome. 
Recognition of this syndrome will reduce misdiagnoses and facilitate appropriate 
treatment.