The in-vitro properties of ceftazidime

Area of Science:

• Microbiology
• Pharmacology
• Infectious Diseases

Background:

• Aminoglycosides are commonly used antibiotics.
• Emerging antibiotic resistance necessitates the evaluation of alternative antimicrobial agents.
• Ceftazidime is a novel cephalosporin with a broad spectrum of activity.

Purpose of the Study:

• To evaluate the in-vitro antibacterial activity of ceftazidime.
• To compare the efficacy of ceftazidime with gentamicin.
• To assess the stability of ceftazidime against beta-lactamases.

Main Methods:

• In-vitro susceptibility testing using minimum inhibitory concentrations (MICs).
• Testing against a panel of Enterobacteriaceae, Pseudomonas species, Staphylococcus aureus, streptococci, and anaerobic bacteria.
• Evaluation of inoculum effects and stability against cell-free beta-lactamases.

Main Results:

• Ceftazidime exhibited high activity against Enterobacteriaceae (MICs 0.07-0.5 mg/l) and Pseudomonas species (all isolates sensitive to 8 mg/l).
• It was as active as gentamicin against gentamicin-sensitive strains and effective against gentamicin-resistant strains.
• Moderate activity was observed against Staphylococcus aureus and Bacteroides fragilis, with high susceptibility in streptococci and other anaerobes.

Conclusions:

• Ceftazidime possesses a broad spectrum of potent in-vitro antibacterial activity.
• Its efficacy against challenging pathogens like Pseudomonas and resistant strains makes it a promising alternative.
• The drug's stability and bactericidal properties further support its potential clinical utility.