Prevalence ofPseudomonas aeruginosapyocin and antibiotic biotypes in four Tehran hospitals

Abstract

Over a 15‐month period, 340 strains of Pseudomonas aeruginosa were isolated from clinical specimens, i.e. sputum, wound swabs, pus, burns, urine, stool, etc., and the environment, i.e. sink, floor, bed sheets, etc., in four Tehran hospitals. Identification of Pseudomonas aeruginosa was carried out by standard methods. Pyocin typing and subtyping were done using the spotting method of Govan, and using a set of 13 indicator strains. Results of the study showed that the dominant pyocin types were PT10, PT4 and PT3, with frequencies of 30.6%, 21.7% and 8.8%, respectively. The pyocins had a wide spectrum of activity, in contrast to most other bacteriocins known. The dominant pyocin subtypes observed in this study were b, d, a, and c, with frequencies of 18.4%, 14.9%, 12.7%, 9.2%, respectively. Approximately 95.9% of the isolates were typable. 98.8% of the Pseudomonas aeruginosa isolates were resistant to 1 or more antibiotics tested. Antibiotic sensitivity tests were performed using the disc diffusion method, ...