Abstract
Cap polyposis is a rare gastrointestinal disease characterized by multiple inflammatory polyps located between the distal colon and the rectum. Despite the lack of clarity regarding its pathogenesis, mucosal prolapse, chronic inflammatory responses, and Helicobacter pylori infection are considered key contributors to the development of this disease entity. Although it is now generally accepted that dysbiosis of gut microbiota is associated with intestinal and extra-intestinal diseases, alterations of intestinal microbiota have been poorly defined in cap polyposis. Here, we report a patient with H. pylori-negative cap polyposis who was successfully treated with antibiotics and exhibited dramatic alterations in intestinal microbiota composition after antibiotic treatment. The patient was treated with oral administration of ampicillin and metronidazole and showed regression of cap polyposis 6 months after antibiotic treatment. Fecal microbiota analysis using the next-generation sequencing technology revealed a significant alteration in the intestinal microbiota composition following antibiotic treatment—a marked reduction of Blautia, Dorea, and Sutterella was observed concomitant with a marked increase in Fusobacterium. These data suggest that cap polyposis may originate from dysbiosis and that microbiome-targeted therapy may be useful in this disorder.
Highlights
Cap polyposis is a rare disease characterized by multiple inflammatory polyps that are covered by a cap of fibrinopurulent mucus and are located between the distal colon and the rectum [1,2,3]
Considering that eradication of H. pylori causes a significant alteration in the intestinal microbiota composition, these case reports suggest that dysbiosisrelated immune responses may underlie the pathogenesis of cap polyposis
We report a patient with H. pylori-negative cap polyposis who was successfully treated using antibiotics
Summary
Cap polyposis is a rare disease characterized by multiple inflammatory polyps that are covered by a cap of fibrinopurulent mucus and are located between the distal colon and the rectum [1,2,3]. The resected specimen showed mucuscontaining distorted glands and significant inflammatory cell infiltration with fibrosis in the lamina propria (Figure 1B) and their surface was covered by inflammatory granulation tissue and fibrinopurulent exudate These endoscopic and histopathological findings were consistent with those typically observed in patients with cap polyposis [1,2,3]. This patient was treated with oral administration of ampicillin (1,500 mg/day) and metronidazole (500 mg/day) for 1 week, and regression of cap polyposis was observed 6 months post-antibiotic treatment (Figure 1C) This clinical course strongly suggests that antibiotic-induced eradication of pathogenic gut bacteria responsible for the development of inflammatory polyps can cause regression of cap polyposis. This microbiota analysis suggests that regression of cap polyposis following antibiotic treatment is accompanied by a marked decrease in Blautia, Dorea, and Sutterella and a marked increase in Fusobacterium, indicating that cap polyposis might have originated from dysbiosis in this patient
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
