[Use of a pair of blood culture bottles for sterility testing of corneal organ culture media]

Abstract

Purpose: To test the effectiveness and rapidity of a pair of blood culture bottles in the diagnosis of bacterial and fungal contamination of corneal organ culture media.

Material: and methods: Seven hundred and sixty one microbiological analysis of storage media (Inosol(R) and Exosol(R), Opsia, Toulouse, France), sampled in all phases of the organ culture at 31 degrees C of 410 consecutive corneas, were analyzed. Each medium was inoculated in a pair of Bactec Plus Aerobic/F(R) and Bactec Lytic/10 Anaerobic/F(R) blood bottles (Becton Dickinson, Cockeysville, MD) and placed in a Bactec 9240 incubator for 14 days at 37 degrees C and in a Sabouraud broth at 20 degrees C. Changes in color or turbidity of storage media were evaluated daily at the corneal bank. Recipients were screened after graft for signs of infection.

Results: The overall contamination rate was 2.4% (18/761). Contamination was detected in less than 1 day in 78% (14/18) and in less than 2 days in 94% (17/18). Positivity of the microbiological controls of starting media preceded medium color changes in 10 out of 14 cases. Bactec blood bottles allowed detection of bacteria as well as Candida sp. yeasts.

Discussion: The use of a pair of aerobic and anaerobic blood culture bottles is a simple, effective and rapid method for the diagnosis of a wide range of microbiological contaminations of organ-cultured corneas during banking.

Conclusion: The validation of this protocol will require a prospective study to compare it with the conventional microbiological method.