Detection of criteria of proteus mirabilis isolates from hospital- and community-acquired infections and their roles in antibiotic resistance

ABSTRACT

Proteus mirabilis; an organism which is oftenly implicated in contamination and colonization, is occasionally isolated in severe hospital infections. The aim of this study was to determine and compare beta -lactamase, ES beta L production, plasmid profile and antimicrobial susceptibility patterns of Pr. mirabilis isolates from in-patients and out-patients of different Jeddah Hospitals, Saudi Arabia. Results showed that the hospitalized Pr. mirabilis isolates were more producers to beta -lactamases [47.1%] than those isolated from the community [36.7%] and flora [13.3%]. Six ES beta Ls-producing Pr. mirabilis isolates were detected in the hospital strains only. About [15.6%] harboured plasmids with molecular weight ranging from 4.3 to 180 Kb. Plasmids were more present in Pr. mirabilis isolates obtained from hospitalized patients [21.6%] than those from the community group [13.4%] and not present in the flora isolates. About [46.2%] and [40%] of hospitalized and community Pr. mirabilis isolates respectively were allocated in antibiotic resistance pattern from AR-P5 toAR-P13. Two ES beta Ls-producing Pr. mirabilis isolates produced beta -lactamases of PIs5.2 and 5.6 were harboured plasmids with molecular weight 180 Kb. The same molecular weight plasmid [180 Kb] was presented in another two ES beta Ls-producing Pr. Mirabilis isolates but they produced another two beta -lactamases [PIs 5.6and 6.3]. Plasmids with molecular weight 25 Kb were presented in strain producing enzyme of PI 5.2 and another strain producing another two enzyme of PIs 5.2 and 5.4. In conclusion any Pr. mirabilis organism which is confirmed for ES beta L -production according to NCCLS criteria can be reported as resistant to all expanded-spectrum beta -lactam antibiotics, regardless of the susceptibility test results: