Ceftazidime-Resistant Pseudomonas Aeruginosa

Ceftazidime-Resistant Pseudomonas Aeruginosa

Ceftazidime continues to show high antipseudomonal activity relative to other drugs

Background

Pseudomonas aeruginosa is a widespread pathogen in the hospital environment that frequently forms “biofilm,” a permanent plaque on medical equipment, and colonizes tissues of long-stay patients. It is considered an opportunistic pathogen, meaning it exclusively strikes affected organ systems of the immunocompromised and seriously ill. Pneumonia, bloodstream, and urinary tract infections are associated with mortality rates that can exceed 50% and high treatment failure because of its intrinsic resistance against many antibiotics.

Ceftazidime and other antipseudomonal cephalosporins are often prescribed in combination with fluoroquinolones or aminoglycosides to circumvent the many resistance mechanisms the pathogen exhibits. The observed stability of ceftazidime resistance rates over time could imply that strains are not acquiring new resistance mechanisms, unlike other Gram-negative pathogens. However, measures to contain the spread of resistant strains are still essential: although in vitro levels remain stable at the national level, individual sites report that multidrug resistance to several agents at once is becoming more common as various resistance mechanisms act in tandem.