The performance of eight methods in identifying Neisseria species, particularly N. gonorrhoeae, was evaluated. These methods included four rapid carbohydrate utilization tests (Gonobio-Test, Neisseria-Kwik, RIM-N, and Minitek); the Gonochek 11, a test which is based on the utilization of chromogenic substrates; and three monoclonal antibody tests (Syva MicroTrak, GonoGen, and Phadebact Monoclonal GC OMNI Test). In all, 182 isolates comprised in six species of Neisseria as well as Branhamella catarrhalis and Moraxella sp. were tested. Cystine-tryptic digest agar supplemented with sugars was included for reference purposes. In the carbohydrate utilization tests, the sensitivity and specificity of the Neisseria-Kwik and Minitek tests for the identification of N. gonorrhoeae were 100%. This compared with sensitivities and specificities, respectively, of 100 and 99.1% for the Gonobio-Test and 99.1 and 100% for cystine-tryptic digest agar sugars and the RIM-N test. The sensitivity and specificity of the Gonochek II test were 99.0 and 86.7%, respectively. Although most test kits did not claim to identify all Neisseria species, in several cases isolates of N. subflava were misidentified or could be misinterpreted as N. gonorrhoeae or N. meningitidis. With the monoclonal reagents, the Syva MicroTrak system was 100% sensitive and 100% specific. The GonoGen test was both 99.1% sensitive and specific, while the Phadebact Monoclonal GC OMNI Test was 99.1% sensitive but 91.2% specific. With this latter test, cross-reactions were observed with strains of B. catarrhalis, N. cinerea, and N. lactamica.

Between October 1987 and June 1989, 84 isolates of Neisseria gonorrhoeae carrying the TetM resistance determinant (TRNG) were received at the Laboratory Centre for Disease Control, Ottawa, from six Canadian provinces and were characterized into classes based on auxotype, serovar and plasmid content. One-fifth (17/84) of the TRNG were also penicillinase producing (PPNG). The PPNG-TRNG isolates comprised six classes based on auxotype, serovar, and plasmid content. Most (16/17) PPNG-TRNG carried 3.2-MDa beta-lactamase plasmids and the 25.2-MDa TetM-containing plasmid. We report, for the first time, the association of a 4.5-MDa beta-lactamase plasmid with the 25.2-MDa plasmid in a clinical TRNG isolate. Non-PPNG TRNG isolates comprised 11 classes based on auxotype, serovar, and plasmid content, including two previously unreported auxotype-serovar classes, P/IB-26 and P/IB-20.

A combination of DNA macrorestriction analysis using pulsed-field gel electrophoresis and a serotyping method using three panels of monoclonal antibody was used to discriminate 43 epidemiologically unrelated Neisseria gonorrhoeae isolates requiring proline, citrulline, and uracil (PCU ؊ ) into 35 groups. This indicates that PCU ؊ isolates of N. gonorrhoeae are not clonal.

suMMARY The analysis of the auxotypes and plasmid profiles of 459 non-PPNG strains from Jamaica suggests that strains have been imported to the island. Unlike in many developing countries where strains are differentiated by only a few auxotypes, 13 different auxotypes were identified in the non-PPNG strains. In Jamaica over 10% of the strains were plasmid free and required proline, citrulline, and uracil (PCU-) for growth. These Gonococcal isolates are differentiated for epidemiological purposes using a combination of techniques. These include assessing nutritional growth requirements (or auxotype),'-' analysing plasmid content,4 6 and characterising strains by serological methods using monoclonal reagents.7 Characterising strains using such methods has facilitated gathering data about the dissemination of both penicillinase producing Neisseria gonorrhoeae (PPNG) and non-PPNG striins.10 13 Relations between the variables serovar, plasmid content, and auxotype are also specific for certain geographical areas and are correlated with other variables, such as susceptibility to antimicrobials and expression of disease.'4'17 Although analyses of the above variables Address for reprints:

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