The antibacterial efficacy of different antipseudomonal agents against Pseudomonas aeruginosa

Severe cases of acute exacerbations of chronic bronchitis (AECB) and communityacquired pneumonia (CAP) are included in Lower respiratory tract infections (LRTIs) also involve hospital acquired pneumonia (HAP); the latter consists of ventilatorassociated pneumonia (VAP) and healthcare-associated pneumonia (HCAP) (Grossman et al., 2005). P. aeruginosa is one of the most common gram-negative bacterial causes of health care-acquired infections (Gaynes and Edwards, 2005; Fluit et al., 2000; Streit et al., 2004). P. aeruginosa is a leading cause of nosocomial infections, ranking second among the gramnegative pathogens reported to the National Nosocomial Infection Surveillance System. There are a limited number of antimicrobial agents with reliable activity against P. aeruginosa, including antipseudomonal penicillins and cephalosporins, carbapenems, and fluoroquinolones, particularly ciprofloxacin. Aminoglycosides are frequently used as part of combination regimens for treatment of serious pseudomonal infections but are generally not recommended as single drug (Carmeli et al., 1999).