OPTIMISATION OF TRANSPORT MEDIA FOR OCULAR ISOLATES

Savitri Sharma

Abstract

To understand the role of bacteria in contact lens-induced adverse ocular responses, microbiological studies of ocular isolates and worn contact lenses are necessary. These studies frequently necessitate transportation of samples, and require a transport medium which neither encourages microbial growth nor results in a loss of viability. To investigate the effect of various transport media on common ocular isolates, the viability of [italics]Staphylococcus aureus, [italics]Staphylococcus epidermidis, [italics]Pseudomonas aeruginosa and [italics]Serratia marcescens, recovered from human corneal ulcers, was tested in five transport media: 0.85% saline, Hank's balanced salt solution, Amie's transport medium, Stuart's transport medium, and 1/4 strength Ringer's solution. Samples were stored in transport medium at 5 or 20 degrees Celsius, and aliquots were cultured at time points ranging from 0 to 2560 minutes. Multivariate statistical techniques were used to establish time limits for recovery of organisms without significant growth or loss of viability. Saline (0.85%) at 5 degrees Celsius was found to be the most satisfactory transport medium, maintaining the viability of all test organisms for at least 10 hours. For exposure times of less than 80 minutes, ocular isolates could be maintained in saline at 20 degrees Celsius without significant change in viability. Amie's medium at 5 degrees Celsius proved the least satisfactory transport medium for all test organisms. These results provide guidelines for storage and transportation of ocular isolates and contact lenses prior to microbiological analysis.

Details

Year: 1992

Program Number: Poster 9

Author Affiliation: n/a

Co-Authors: Jo-Anne Chuck, KR Lakshmi, Madhukar Reddy, Claire Fleming, Deborah Sweeney

Co-Author Affiliation: n/a

Room: Great Hall