Enterotoxin production by Staphylococcus aureus isolates from cases of septicaemia and from healthy carriers

Department of Clinical Microbiology, St James's Hospital, Dublin 8, Moyne Institute, Department of Microbiology, Trinity College, Dublin 2, Department of Microbiology, The Mater Misericordiae Hospital, Dublin 9, Ireland Correspondence should be addressed to Dr D. C. Coleman. Received March 24, 1988 Accepted June 12, 1988 In a prospective study, 52 Staphylococcus aureus isolates from individual patients with septicaemia and 27 nasal strains from separate, healthy carriers were compared for production of a range of extracellular proteins and toxins. Whereas there was no difference (p > 0·05) between septicaemic and nasal isolates with respect to incidence of , β, and · haemolysins, toxic shock syndrome toxin-1 or staphylokinase production, the incidence of enterotoxin A, B, and C production was higher among isolates from septicaemia (p < 0·01). Of the isolates from septicaemia, 33 (63%) produced enterotoxins A, B, C or D alone or in combination. Only three (11%) of the nasal isolates produced a single enterotoxin, enterotoxin D. Of the isolates from septicaemia, 67% were hospital-acquired and > 25% of these were endemic, methicillin-resistant (MRSA) strains. All MRSA strains produced either enterotoxin A, or enterotoxin B, or both. These findings suggest a possible role for enterotoxins in the pathogenesis of S. aureus disease other than food poisoning. * Present address: Department of Microbiology, Bristol Royal Infirmary, Bristol BS2 8HW.