Chromosomally mediated resistance in Neisseria gonorrhoeae in the United States: results of surveillance and reporting, 1983-1984.

Between January 1983 and October 1984, 446 cases of infection due to chromosomally mediated resistance in Neisseria gonorrhoeae (CMRNG) were reported in 23 states. Eighty percent were detected as primary penicillin or ampicillin treatment failures. Gonococcal isolates were submitted from 175 (40%) for confirmation of resistance, susceptibility testing, gonococcal strain typing using monoclonal antibodies specific for outer membrane Protein I, and auxotyping. All were typed as Protein I serogroup IB (WII/WIII), and the majority were proline or prototrophic auxotypes. All were resistant in vitro to less than 1 microgram/ml of either penicillin or tetracycline. Comparing CMRNG with penicillinase-producing Neisseria gonorrhoeae (PPNG), we found that CMRNG were significantly more resistant to tetracycline and erythromycin, but PPNG were more resistant to penicillin (P less than .01). Because of increasing reports of gonococcal resistance in the United States, improved surveillance of clinical and laboratory resistance is needed in support of control and treatment recommendations for gonorrhea.