Campylobacter cinaedi (sp. nov.) and Campylobacter fennelliae (sp. nov.): two new Campylobacter species associated with enteric disease in homosexual men.

In a recent study in Seattle, we isolated Campylobacter-like organisms (CLOs) significantly more often from homosexual men with intestinal symptoms than from asymptomatic heterosexual and homosexual control subjects. Biochemical tests, morphology, and guanine-plus-cytosine content of whole-cell DNA showed that these organisms were similar to, but distinguishable from, other species in the genus Campylobacter. DNA homology tests showed that the Campylobacter-like organisms belong to four unique genetic groups, two of which were phenotypically identical. We developed a rapid screening test to genetically group these organisms and to assess the correlation of each genotype with enteric disease in homosexual men. Three of the four CLO groups were isolated only from men with proctitis, proctocolitis, and/or enteritis. The remaining group, isolated from both symptomatic and asymptomatic homosexual men, was significantly correlated with the presence of polymorphonuclear leukocytes in the rectal secretions of asymptomatic men, a finding that suggests subclinical disease. We have tentatively classified two of the CLO groups into species, Campylobacter cinaedi sp. nov. and Campylobacter fennelliae sp. nov.