Clinical significance of human intestinal spirochetosis: a retrospective study

Abstract

The clinical and pathological features of human intestinal spirochetosis (HIS) are not well known. Here we report 55 patients with HIS who were diagnosed at our institution during the past 5 years. Seven patients presented with symptoms such as abdominal pain or diarrhea, while the others were incidentally diagnosed during screening colonoscopy. Most patients had non-specific endoscopic findings, including intestinal edema or erosion. The diagnosis of HIS was histologically confirmed via hematoxylin and eosin staining, periodic acid-Schiff staining, and/or immunohistochemistry using anti-Treponema pallidum antibody. Among the 55 patients, five were diagnosed with diseases other than HIS (amoebic colitis, three;ulcerative colitis, one). Sixteen patients were treated with either amoxicillin or metronidazole;only metronidazole proved to be effective. The clinical significance of asymptomatic HIS remains unknown. Some case reports suggest a risk for increased severity in patients with immunodeficiency and/or sexually transmitted diseases. Therefore, aggressive treatment for HIS should be considered, particularly in high-risk patients.