Serious infection due to an outbreak of aminoglycoside resistant pseudomonas aeruginosa serotype 0: 12,pyocine type 1b, in an intensive care unit

ABSTRACT

An outbreak of aminoglycoside-resistant pseudomonas aeruginosa occurred during the months of November 1983 to February 1984, among 14 patients admitted to the ICU of Dammam Central hospital. All the strains were resistant to gentamicin, tobramycin, sisomicin and carbenicillin; and six strains were in addition, resistant to amikacin. The index case appeared to be a patient admitted with multiple fractures following a motor vehicle accident from whom the resistant strain was isolated on the fourth day following admission to the unit. The outbreak was controlled only after the unit was closed for 1 week. Epidemiological investigations failed to reveal the mode of transmission, but the sinks were found to harbour this strain in large quantities. O-serotyping showed all the strains belonged to serotype 012. They all belonged to pyocine type 1 b and were lysed by a single phage [phage 68]. Aminoglycoside degrading enzymes were not detected in ultrasonic extracts of any of the strains