Antimicrobial resistance among non-fermenting Gram-negative bacteria in Saudi Arabia

OBJECTIVES: Non-fermentative Gram-negative bacilli (non-fermenters) can cause serious healthcare-associated infections and are often resistant to multiple antibiotics. We examined resistance rates among these bacteria from different regions of Saudi Arabia. METHODS: A cross-sectional study between January and December 2009 examined 8908 clinical non-fermenters from 24 hospitals across Saudi Arabia. Susceptibility testing was monitored to ensure compliance with CLSI guidelines, but the antibiotics tested were at the hospitals' discretion. RESULTS: Out of the 8908 non-fermenters, most were Pseudomonas aeruginosa (72.9%), followed by Acinetobacter baumannii (25.3%) and Stenotrophomonas maltophilia (1.8%). Resistance rates among P. aeruginosa were: polymyxin B, 2.2%; imipenem, 15.9%; ciprofloxacin, 22.0%; amikacin, 22.9%; and gentamicin, 31.2%. Resistance rates among A. baumannii were: imipenem, 5.4%; polymyxin B, 13.2%; ciprofloxacin, 64.0%; trimethoprim/sulfamethoxazole, 73.8%; amikacin, 76.9%; and gentamicin, 77.8%. Resistance rates among S. maltophilia were: polymyxin B, 6.9%; trimethoprim/sulfamethoxazole, 20.5%; and ciprofloxacin, 38.9%. There was major variation in resistance rates between geographical regions. CONCLUSIONS: Resistance rates among non-fermenters were high in Saudi Arabia and were variable among regions.