Problems in the investigation of an apparent outbreak of coagulase-negative staphylococcal septicaemia following cardiac surgery.

Two hundred and twenty-six hospital staff and patients were investigated for the carriage of gentamicin-resistant coagulase-negative staphylococci (CNS) during an apparent outbreak of infection after cardiac surgery. Of the four index strains from infected wounds, three were indistinguishable. The carriage of similar organisms was widespread, particularly among ITU staff (72%) and patients. Ninety-one of the 296 gentamicin-resistant isolates were further investigated, and of these 33 were indistinguishable from index strains even with the use of specialized techniques. Our experience indicates that in outbreaks of infection caused by gentamicin-resistant CNS, resources should be focused on the interruption of transmission and prevention of introduction of these organisms to susceptible patients.