Ophthalmology Review Journal

Glaucoma

Purpose:
To determine whether microorganisms are able to survive in a solution of 50 mg/ml of 5-fluorouracil (5-FU) and, therefore, whether there is a risk of vial contamination with multiple use.

Methods:
Ten common nosocomial pathogens were tested. Minimal inhibitory concentrations (MICs) of 5-FU were determined for each organism. Organisms were then inoculated into 1 ml of 5-FU (50 mg/ml) and, after timed periods of exposure, were plated onto blood agar and incubated at 37 degrees C. Plates were checked daily for the presence or absence of growth.

Results:
The MICs of Klebsiella pneumoniae and Pseudomonas cepacia were within one log unit of the 10 mg/ml concentration of 5-FU used by some clinics. After incubation in 5-FU for 1 h, all species survived; after 24h of exposure, five of the 10 species-Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, K. pneumoniae, and Proteus mirabilis-were still viable.

Conclusion:
5-FU has limited bactericidal activity, and there is a risk of contamination if 5-FU vials are used in multiple dose fashion.

Authors' abstract, JGlauc
San Francisco, CA