title: Human intestinal spirochetosis: right-side preference in the large intestine.
abstract: Human intestinal spirochetosis (HIS) is a colorectal bacterial infection, and its clinicopathologic features remain unclear. The aim of this study was to examine its characteristics. We histologically reviewed paraffin-embedded section slides made in 2001, 2006, and 2011 at a single institution in Japan. Cases histologically exhibiting a distinct fringe formation were considered to have HIS. Information was obtained from pathology request forms. We identified 85 HIS cases among 4930 patients (7 cases [0.5%) in 2001, 29 [1.7%] in 2006, and 49 [2.8%] in 2011]. Gastrointestinal symptoms were observed in 7.1% of HIS cases. Human intestinal spirochetosis was more frequent in the right-side large intestine than in the left side. Among 224 samples from HIS cases, conventional (tubular, tubulovillous, and villous) adenomas were found in 148 samples. These adenomas were more frequent in the right side than in the left side, although neither their size nor morphology differed between the sides. Histopathologic evaluation suggested a year-upon-year increasing prevalence of HIS in Japan. A small number exhibited gastrointestinal symptoms. Both histologic sign of HIS and conventional adenomas were more frequent in the right-side large intestine. Therefore, a right-side preference may be a characteristic of HIS.
authors.affiliation: Department of Laboratory Medicine, National Defense Medical College Hospital, Tokorozawa, Saitama 359-8513, Japan; Department of Diagnostic Pathology, JCHO Saitama Medical Center, Saitama, Saitama 330-0074, Japan. Electronic address: sogata@ndmc.ac.jp.
authors.forename: Sho
authors.initials: S
authors.lastname: Ogata
authors.affiliation: Department of Diagnostic Pathology, JCHO Saitama Medical Center, Saitama, Saitama 330-0074, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Shimizu
authors.affiliation: Department of Laboratory Medicine, National Defense Medical College Hospital, Tokorozawa, Saitama 359-8513, Japan; Department of Pathology and Laboratory Medicine, National Defense Medical College, Tokorozawa, Saitama 359-8513, Japan.
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Nakanishi
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005767:Gastrointestinal Diseases / Q000382:microbiology / Q000473:pathology*; D006801:Humans; D007413:Intestinal Mucosa / Q000382:microbiology / Q000473:pathology*; D007420:Intestine, Large / Q000382:microbiology / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D013145:Spirochaetales Infections / Q000473:pathology*
keywords: Adenoma; Brachyspira; Location; Spirochetosis