A comparison of three fermentation methods for the confirmation of Neisseria gonorrhoeae

When confirming suspected isolates of Neisseria gonorrhoeae, laboratories use a fluorescent antibody method or a fermentation technique, usually the cystine-trypticase agar (CTA) semisolid. Suspected N. gonorrhoeae from sites such as the throat, rectum, and blood require this confirmation. The modified rapid fermentation test (MRFT) was compared with the standard CTA and the Mueller-Hinton agar (MHA) slant methods. The MRFT appeared to have greater sensitivity than the other two methods, and results could be obtained within a 4-hour period as compared with overnight for the other two methods. The MRFT gave quicker results with greater sensitivity than either the MHA slant or the CTA semi-solid techniques.