Antibiotic resistance among Gram-negative non-fermentative bacteria at a teaching hospital in Saudi Arabia.

The incidence and antimicrobial resistance of Gram-negative non-fermentative bacteria isolated over 1 year at King Abdulaziz University Hospital, Jeddah, Saudi Arabia were investigated. A total of 499 of these microorganisms were collected and account for 16% of all Gram-negative bacteria isolated. The most common species were Pseudomonas aeruginosa 291 (56%), Acinetobacter baumannii 170 (34%), and Stenotrophomonas maltophilia 35 (7%). 168 (34%) of these microorganisms were isolated from Intensive Care Unit (ICU), 147 (30%) from General Medicine, and 24 (25%) from Surgery wards. ICU was the main site of isolation of P. aeruginosa and S. maltophilia, while A. baumannii was more frequently isolated from medicine and surgery units. The vast majority of the isolates were resistant to many antibiotics tested. The antimicrobial resistance patterns of P. aeruginosa showed lowest resistance to imipenem (13%), amikacin (17%), and ciprofloxacin (18%). Imipenem was also the most active antimicrobial agent against A. baumannii (15%) resistance. S. maltophilia exhibited multi-drug resistance, and was susceptible only to sulfonamide (6%).