Serovars and serum resistance of Neisseria gonorrhoeae from disseminated and uncomplicated infections.

Two hundred and seventy-four gonococcal strains isolated from patients with either disseminated (DGI) or uncomplicated (UG) infection were examined to determine their serotypes/serovars by two typing systems as well as their resistance to the bactericidal action of normal human serum. The bactericidal assays were performed in particular to determine whether isolates from patients with the clinical syndrome of DGI but negative systemic cultures (suspected DGI) were serum-susceptible. When strains containing protein IA in their outer membranes and having auxotypes other than the arginine-hypoxanthine-uracil requirement were serotyped, a significant difference was found in the distribution of serovars among strains from DGI and suspected DGI compared with UG. The two typing systems revealed both antigenic similarities and differences of gonococci from Chicago and isolates from Germany reported in another study. Like DGI strains, most suspected DGI strains contained protein IA and were resistant to the bactericidal action of serum.