Phenotypic characteristics of Serpulina pilosicoli the agent of intestinal spirochaetosis

Abstract

The phenotypic characteristics of three Serpulina pilosicoli strains isolated from humans with diarrhoea (WesB, Kar, Hrm7) and two porcine S. pilosicoli strains isolated from pigs with intestinal spirochaetosis (1648, 3295), were compared with the type strain of the species P43/6/78T (T = type strain) and other intestinal spirochaetes within the genus Serpulina. All S. pilosicoli strains had a characteristic ultrastructural appearance, displayed similar growth rates, hydrolysed hippurate, lacked beta-glucosidase activity, utilised D-ribose as a growth substrate, and had similar sensitivities to rifampicin and spiramycin. The only consistent phenotypic characteristic that differentiated human strains from porcine strains of S. pilosicoli was that the human strains all utilised the pentose sugar D-xylose. These distinguishing phenotypic traits appear useful for identifying S. pilosicoli.

The prevalence of Serpulina pilosicoli in humans and domestic animals in the Eastern Highlands of Papua New Guinea

“…These previous studies were conducted prior to the classification of S. pilosicoli as a new species, and no attempt was made at the time to identify the intestinal spirochaetes isolated. Recently strains from these studies in Oman and in an Aboriginal community in Western Australia, as well as strains from Italy, New South Wales, the United Kingdom, and the United States have been confirmed as S. pilosicoli [6,18]. The present study conducted in PNG is the first large scale attempt to specifically determine the prevalence of S. pilosicoli in humans and animals living in close proximity.…”

“…In many of these studies, the aetiological agent was never cultured or was presumed to be Brachyspira aalborgi, a species of intestinal spirochaete that has only been isolated from humans on one occasion, and is presumed to be non-pathogenic [16,17]. Recently it has been demonstrated that spirochaetes in some of these studies were S. pilosicoli [6,18]. Furthermore, the potential significance of S. pilosicoli as a human pathogen has been highlighted by its recent isolation from the bloodstream of debilitated patients [19].…”

In Vitro Activity of Four Antimicrobial Agents against North American Isolates of Porcine Serpulina Pilosicoli

“…2,[14][15][16]20,21,29,30,38 Diarrheal disease and reduced performance associated with S. pilosicoli have been reported from all major swine producing countries of North America, Europe, and Australia. 1,5,6,9,10,12,19,[24][25][26][27][32][33][34][35][36][37] The prevalence of S. pilosicoli infection in finisher farms of a multisite production system in the United States was estimated recently to be approximately 50%. 5 The results of in vitro antimicrobial susceptibility of North American isolates of porcine S. pilosicoli suggested that carba- dox and tiamulin may be suitable for control of PCS.…”

“…7,13,31 However, an association between a WBHIS, recently classified as S. pilosicoli, and a nonfatal diarrheal disease of growing pigs, called porcine intestinal spirochetosis or porcine colonic spirochetosis (PCS), has been recognized. 1,[5][6][7][8][9][10][11][12]19,[24][25][26][27][28][32][33][34][35][36][37] With more intensive swine production, where the efficiency of weight gain is closely monitored, PCS has been recognized as a major contributing factor to reduced performance in growing and finishing pigs. 5,6,8,9,10,12,34 Koch's postulates for S. pilosicoli have been fulfilled using gnotobiotic pigs 25 and conventional pigs.…”

“…Preliminary reports on the in vitro activity of antimicrobial agents against a few Australian and Swedish isolates of porcine S. pilosicoli suggest that antimicrobial susceptibility of S. pilosicoli is similar to that of S. hyodysenteriae. 8,9,36,37 In the present study, the in vitro antimicrobial susceptibilities of the reference isolate S. pilosicoli P43/6/78 from the United Kingdom and 19 isolates obtained from pigs in Canada (n ϭ 5) and the United States (n ϭ 14) were determined for carbadox, gentamicin, lincomycin, and tiamulin, four antimicrobials commonly used for control of the closely related pathogenic intestinal spirochete, S. hyodysenteriae. Additionally, the susceptibility or resistance of each isolate against each antimicrobial agent was estimated on the basis of available data for the in vitro antimicrobial susceptibility breakpoints of S. hyodysenteriae.…”