Submitted to: Journal of Infectious Diseases
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/30/1996
Publication Date: N/A
Interpretive Summary: Serpulina hyodysenteriae and Serpulina pilosicoli are spirochetes (spiral- shaped bacteria) that cause diarrheal diseases in pigs and, in the case of Serpulina pilosicoli, poultry, dogs, and humans. Serpulina hyodysenteriae causes the disease swine dysentery which has an economic impact of $100 million per year. The economic impact of Serpulina pilosicoli has not been determined; however, reports from diagnostic laboratories indicate Serpulina pilosicoli is found more often than Serpulina hyodysenteriae in porcine intestinal and fecal samples. In pigs, Serpulina pilosicoli causes a moderate diarrheal disease and decreased weight gain. In addition, Serpulina pilosicoli has been isolated from the intestines of AIDS patients and homosexual males, and from people in developing countries (i.e., with poor diets). Recently, 7 spirochete strains were isolated from the blood of severely ill people in France. Initially, these spirochetes were identified as strains of Serpulina hyodysenteriae. However, as part of an international collaborative effort, we found that these spirochetes were Serpulina pilosicoli. This information will alert porcine and poultry producers to the increasing host range of Serpulina pilosicoli. In addition, this information will be of use to both human and veterinary diagnostic laboratories for the more accurate diagnosis of disease conditions.
Technical Abstract: The phenotypic and genetic characteristics of 7 spirochetes isolated from the blood of patients with severe clinical disease or impaired immunity were examined. The isolates were identified as Serpulina pilosicoli, a recently-named intestinal spirochete which is the agent of porcine intestinal spirochetosis, a diarrheal disease of swine. This spirochete also has been isolated from the gastrointestinal tract of human beings and other animal species, but this is the first report of the organism being isolated from extraintestinal sites. Genetic variation amongst the strains and genetic relationships to strains isolated from the intestinal tract of humans were demonstrated by multilocus enzyme electrophoresis. Although concurrent fecal culture was not documented for any of the patients, it appears likely that the strains of S. pilosicoli isolated from blood translocated from the intestine. Additional research is required to determine the significance of S. pilosicoli bacteremia.