Control of an outbreak of diarrhoea in a vascular surgery unit caused by a high-level clindamycin-resistant...

This report describes an outbreak of Clostridium difficile infection (CDI) in a vascular surgery ward in 2009 caused by a high-level clindamycin-resistant ribotype 106. A case of CDI was defined as a patient with diarrhoea, positive for C. difficile toxin and negative for other enteric pathogens. Cultures were sent to the Scottish Salmonella Shigella and Clostridium difficile Reference Laboratory (SSSCDRL) for PCR ribotyping, antibiotic susceptibility testing and PCR detection of ermB. The mean age of the nine patients was 73 years (range: 38-90 years). All had received clindamycin and ciprofloxacin. All cases were typed as PCR ribotype 106 and they showed high-level resistance to clindamycin. Five of these isolates were tested by PCR for the presence of the ermB gene and no amplification was detected. This strain has rarely been isolated from patients on this ward. The outbreak was controlled successfully by closure of the ward with terminal cleaning, reinforcement of infection control precautions and the introduction of a new antibiotic policy. It is notable that this outbreak was caused by a strain with high-level clindamycin resistance not mediated by ermB. It also re-emphasizes that outbreaks of CDI can be caused by C. difficile PCR ribotypes other than 027. The outbreak was most likely associated with the use of clindamycin and ciprofloxacin cross-infection with spores in this environment. Implementation of strict infection control precautions, antimicrobial stewardship and enhanced environmental cleaning are key components in managing such an outbreak successfully. The number of meticillin-resistant Staphylococcus aureus acquisitions also fell substantially after these interventions.