Experimental infection of C3H mice with avian, porcine, or human isolates of Serpulina pilosicoli

Intestinal spirochetosis in humans (HIS) is a condition defined by the presence of a layer of spirochetes attached by one cell end to the colorectal epithelium. The pathologic significance of HIS is uncertain, but it has been linked to chronic diarrhea and other abdominal complaints. Two anaerobic intestinal spirochete species have been associated with HIS, namely Brachyspira pilosicoli and Brachyspira aalborgi. Brachyspira pilosicoli, which colonizes many animal species, is common (~30%) in the feces of people from developing countries, including Australian Aborigines, and in HIV+ patients and male homosexuals in Western societies. It is also commonly seen attached to the rectal mucosa of homosexual males. In other groups in Western societies both the presence of B. pilosicoli in feces and histologic HIS are uncommon (~1.5%). Brachyspira aalborgi is an extremely slow growing and fastidious spirochete, which previously had been isolated from an HIS patient in Denmark. Recent studies using polymerase chain reaction amplification of DNA from intestinal biopsies from a series of cases of HIS in the general Western population demonstrated that B. aalborgi, rather than B. pilosicoli, was the main spirochete species involved in these patients. This review outlines recent developments in the study of HIS and the two spirochete species, and identifies priorities for future research.

Section: Brachyspira (Serpulina) Pilosicolimentioning

confidence: 99%

Human intestinal spirochetosis:Brachyspira aalborgiand/orBrachyspira pilosicoli?

Mikosza

Hampson

2001

“…co-workers (Trott et al, 1995, 1996a; produced diarrhea and colonic lesions both in pigs and chicks, challenged with human B. pilosicoli strains. Similarly, Muniappa et al (1996) and Sacco et al (1997), respectively, produced lesions in chicks and laboratory mice challenged with human B. pilosicoli. Therefore, it appears that B. pilosicoli has pathogenic potential in dogs, pigs and birds.…”

Section: Introductionmentioning

confidence: 93%

Human intestinal spirochetosis diagnosed with colonoscopy and analysis of partial 16S rDNA sequences of involved spirochetes

Kraatz

Thunberg

Pettersson

et al. 2001

DNA was extracted from colonic biopsies of 33 patients with and three without evidence of intestinal spirochetosis (IS) in the large bowel. The biopsies were subjected to PCR. A pair of primers, generating a 207 bp fragment, were designed to detect specifically the 16S rDNA gene ofBrachyspira. PCR products of the expected size were obtained from 33 samples with histologic evidence of IS. The PCR amplicons were used for sequencing. The sequences obtained were aligned to the corresponding 16S rRNA sequences of five type strains ofBrachyspira. The sequences of 23 PCR products were 99–100% identical with the correspond-ingB.aalborgitype strain sequence. Two cases showed 99–100% sequence similarity with the type strain ofB.pilosicoliP43/6/78. Six cases could not be referred to any of the known species ofBrachyspira. Two PCR products gave incomplete sequences.

“…Koch's postulates have been fulfilled for B. pilosicoli as a cause of CS in conventional pigs (Taylor et al, 1980;Trott et al, 1996c;Thomson et al, 1997;Duhamel, 1998;Jensen et al, 2000), gnotobiotic pigs (Neef et al, 1994), 1-day-old chicks (Dwars et al, 1992;Trott et al, 1995;Muniappa et al, 1996Muniappa et al, , 1998Webb et al, 1997; and laboratory mice (Sacco et al, 1997). In most animal models, the rate of infection after oral inoculation is usually greater than 75%; however, only 17-67% of challenged pigs develop diarrhea (Table 1).…”

Section: Animal Models For Colonic Spirochetosismentioning

confidence: 99%

“…In most animal models, the rate of infection after oral inoculation is usually greater than 75%; however, only 17-67% of challenged pigs develop diarrhea (Table 1). In contrast, diarrhea is usually not seen in challenged chicks and laboratory mice in spite of persistent cecal infection (Trott et al, 1995;Muniappa et al, 1996Muniappa et al, , 1998Sacco et al, 1997). However, watery diarrhea and decreased weight gain have been reported in chicks challenged with certain strains of B. pilosicoli (Trott et al, 1995;.…”

Section: Animal Models For Colonic Spirochetosismentioning

confidence: 99%

See 1 more Smart Citation

Comparative pathology and pathogenesis of naturally acquired and experimentally induced colonic spirochetosis

Duhamel

2001

Research in the past decade has led to the recognition of Brachyspira (formerly Serpulina) pilosicoli as the primary etiologic agent of colonic spirochetosis (CS), an emerging cause of colitis in humans and animals. Attachment of spirochetes to the epithelial surface of the lower intestine is considered to be the hallmark of CS. However, because B. pilosicoli, B. aalborgi and unclassified flagellated bacteria are found singly or together in humans and non-human primates with CS lesions, attachment of spiral-shaped bacteria may not represent the same etiopathogenetic entity in all hosts. Moreover, North American opossums with CS are infected with B. aalborgi-like spirochetes together with flagellated bacteria, whereas B. pilosicoli is found alone in dogs, pigs, chickens and other species of birds with CS. Conversely, guinea-pigs with CS have unidentified spirochetes that may be B. pilosicoli or B. aalborgi. The pig model of CS suggests that attachment of B. pilosicoli to epithelial cells may be transient. By contrast, persistence of B. pilosicoli in the cecal and colonic crypt lumina, chronic inflammation caused by spirochetal invasion into the subepithelial lamina propria and translocation to extraintestinal sites may be more important than previously thought. This review describes the lesions seen in naturally occurring and experimentally induced CS of animals, and it sets the stage for future research into the pathogenic mechanisms of infection and colitis caused by B. pilosicoli.