Killing efficacy of a new hypothermic corneal storage medium Kerasave at 4°C against nine micro-organisms frequently found in donor corneas

PURPOSE
The aim of the present study was to determine the killing efficacy of Kerasave (AL.CHI.MI.A Srl), a corneal cold storage medium provided with antimycotic tablet against nine contaminants associated with corneal infections.

METHODS
The killing efficacy of Kerasave was determined after 0, 3 and 14 days of incubation at 4°C in Kerasave after inoculation of the medium with 10(5)–10(6) (CFU) of Candida albicans (CA), Fusarium solani (FS), Aspergillus brasiliensis (AB), Staphylococcus aureus (SA), Enterococcus faecalis (EF), Bacillus subtilis spizizenii (BS), Pseudomonas aeruginosa (PA), Enterobacter cloacae (EC) and Klebsiella pneumoniae (KP). Log10 reductions at different time intervals were determined by the serial dilution plating technique.

RESULTS
After 3 days, Kerasave induced the highest log10 decrease in the concentrations of KP, PA, CA and EC. The 2 log10 decrease was observed for SA and EF. The lowest log10 decrease was observed in BS, AB and FS concentrations. After 14 days, the microbial count of CA, FS, SA, EF, PA and EC further decreased.

CONCLUSIONS
Corneal cold storage medium Kerasave effectively reduced the microbial concentration of almost all tested microorganisms after 3 days and represents a valuable tool to control the microbial contamination of human donor corneas intended for transplantation.