Pseudomonas aeruginosa bacteraemia in an academic hospital in South Africa

The aim of the study was to determine the clinical manifestations, outcome of and prognostic factors associated with Pseudomonas aeruginosa bacteraemia at Chris Hani Baragwanath Hospital, Johannesburg, during the period 1998 - 1999, to describe and quantify resistance to antipseudomonal drugs, to characterise bacteraemic isolates, and to investigate the clustering and genotype distribution of drug-susceptible and multiply-resistant strains in the hospital.

Clinical and laboratory investigations, culture and antimicrobial susceptibility testing were performed. Bacteraemic isolates were typed by endonuclease macrorestriction. Those with > or = 97% band pattern similarity were assigned genotype status.

Of 91 P. aeruginosa blood isolates, 52 (57.1%) were nosocomially acquired. Underlying conditions associated with episodes were burns in 24 (28%) and HIV infection in 21 (24%). Multidrug resistance was present in 14 (15.4%) of isolates from 91 episodes. In 79 episodes where the outcome was known, 37 (46.8%) of the patients died. Case fatality rates were 75% in adults and 25% in children. Being a child, receiving appropriate antimicrobial treatment and admission to a specialised care unit were significantly associated with improved prognosis.

P. aeruginosa bacteraemia was associated with outbreaks caused by two multiply-resistant genotypes. Eighteen antimicrobial-susceptible isolates from bacteraemic episodes in paediatric wards, 9 in HIV-seropositive children, could be linked to small outbreaks in both hospitalised and community-based children.