Related Experiment Videos
Ceftazidime concentrations in human aqueous humor
Abstract:
Two grams of ceftazidime was given to 25 patients before cataract surgery. Mean aqueous humor concentrations of 2.8, 3.2, 3.39, and 1.94 micrograms/mL were observed 30 minutes and 1, 2, 4, and 6 hours, respectively, after administration of the drug. These concentrations are many times higher than the minimum inhibitory concentration (MIC) of ceftazidime against 90% ( MIC90 ) of isolates of Escherichia coli, Klebsiella sp, Proteus mirabilis, and indole-positive Proteus sp. The peak aqueous humor level was also equivalent to or slightly higher than the MIC90 for Pseudomonas aeruginosa.
Insights
Ceftazidime administered before cataract surgery achieved high aqueous humor concentrations, exceeding the minimum inhibitory concentration (MIC) for common bacteria including Pseudomonas aeruginosa.
Area of Science:
- Ophthalmology
- Pharmacology
- Microbiology
Background:
- Cataract surgery poses a risk of postoperative ocular infections.
- Antibiotic prophylaxis is crucial to prevent bacterial endophthalmitis.
- Ceftazidime is a broad-spectrum cephalosporin with activity against Gram-negative bacteria, including Pseudomonas aeruginosa.
Purpose of the Study:
- To determine the concentration of ceftazidime in the aqueous humor following preoperative administration.
- To assess whether achieved concentrations are sufficient to inhibit common ocular pathogens.
Main Methods:
- Twenty-five patients undergoing cataract surgery received two grams of ceftazidime preoperatively.
- Aqueous humor samples were collected at various time points (30 minutes, 1, 2, 4, and 6 hours) post-administration.
- Drug concentrations were quantified and compared to minimum inhibitory concentrations (MIC90) of relevant bacteria.
Main Results:
- Mean aqueous humor concentrations ranged from 1.94 to 3.39 micrograms/mL between 30 minutes and 6 hours post-administration.
- Achieved concentrations were significantly higher than the MIC90 for Escherichia coli, Klebsiella sp, Proteus mirabilis, and indole-positive Proteus sp.
- Peak aqueous humor levels met or exceeded the MIC90 for Pseudomonas aeruginosa.
Conclusions:
- Preoperative administration of two grams of ceftazidime results in substantial intraocular concentrations.
- These concentrations provide adequate therapeutic levels against a wide range of potential bacterial pathogens implicated in postoperative endophthalmitis.