Outbreak of Pseudomonas aeruginosa bacteraemia in a haematology department.

INTRODUCTION

Infection by Pseudomonas aeruginosa represents a major cause of morbidity and mortality among immunocompromised patients. In Denmark, an increase in P. aeruginosa isolates from blood cultures from a haematology department prompted a hygienic audit in 2007.

METHODS

Blood cultures that tested positive for P. aeruginosa were collected from the laboratory information system (MADS, Skejby Hospital, Aarhus, Denmark). Environmental samples were obtained from shower heads in the department. The genotype was established by pulse field gel electrophoresis (PFGE). An audit was conducted during the outbreak and 12 months later. The audits were conducted by the method of direct observation.

RESULTS

Several PFGE types were involved with no clear association to isolates from environmental samples. The audit revealed poor hygiene related to the handling of central venous catheters. After optimising catheter hygiene, the number of P. aeruginosa bacteraemia cases fell significantly.

CONCLUSION

Since no clear association between patient and environmental genotype was established, it was suspected that central venous catheters were the main portal of entry. This was further supported by a simultaneous decline in bacteraemia cases with coagulase-negative staphylococci. Though several hygienic precautions were taken, the increased focus on disinfection of hubs and injection ports was presumably the more important element.

FUNDING

not relevant.

TRIAL REGISTRATION

not relevant.