Evaluation of the Phadebact Gonococcus Test in the identification of Neisseria gonorrhoeae in a routine diagnostic laboratory.

The Phadebact Gonococcus Test, a coagglutination procedure for the confirmation of identity of presumptive N gonorrhoeae isolates, was evaluated under normal working conditions in a routine diagnostic laboratory and compared with an immunofluorescence technique. Of 166 isolates of N gonorrhoeae from urogenital, rectal, and pharyngeal sites, 164 gave a positive coagglutination reaction, and one of the two negative isolates gave a positive reaction on retesting after subculture. There were no cross-reactions with other organisms tested. This was in contrast with the immunofluorescence technique; with this method, three of 46 isolates of N meningitidis fluoresced brightly, and a further 17 isolates of N meningitidis gave reactions that were difficult to interpret. The coagglutination test is rapid, simple and a more specific alternative to immunofluorescence.