Comparative performance of commercial Amies transport media with and without charcoal for Neisseria gonorrhoeae culture for gonococcal isolation and antimicrobial resistance monitoring in Ukraine.

INTRODUCTION: Culture is the only laboratory method that provides live gonococcal isolates for monitoring antimicrobial resistance. Many clinical settings do not have direct access to laboratories for the immediate processing of biological samples. Validated and quality-assured transport media are recommended to maintain the viability of Neisseria gonorrhoeae.
METHODS: In total, 103 clinical samples were divided into two groups: 51 samples were stored in Amies agar gel medium containing charcoal and 52 samples were stored in agar gel medium without charcoal. All samples were stored at 4°C for 0.5-6 h and then transported in a thermo-protected box within 0.17-0.25 h to the laboratory of Ternopil Regional STI Clinic (Ukraine).
RESULTS: The recovery rate was significantly higher for charcoal-containing Amies medium than for charcoal-free Amies medium (86.27%, 44/51 vs. 59.62%, 31/52). A higher rate of specimens transported in charcoal-containing Amies medium was isolated within 24 h (84.31%, 43/51), whereas most isolates from charcoal-free Amies medium grew within 24 h (42.31%, 22/52) or 48 h (17.31%, 9/52). Growth beyond the first quadrant of the agar plate was registered for 59.09% (26/44) of charcoal-containing Amies samples, compared with only 19.35% (6/31) of charcoal-free Amies samples.
CONCLUSIONS: A high rate of N. gonorrhoeae recovery after transport has considerable public health implications for establishing national antimicrobial susceptibility programs. Charcoal-containing Amies medium had higher viability rate, and it could be used for diagnostic and isolation purposes in future antimicrobial susceptibility studies. Continuous validation studies of transport medium for N. gonorrhoeae culture are needed. GERMS.