Cap polyposis in a child: A rare cause of rectal bleeding

S Arulprakash; Tarun George; Malathi Sathiyasekaran

doi:10.4103/ghep.ghep_6_20

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CASE REPORT

Year : 2021 | Volume : 1 | Issue : 1 | Page : 34-36

Cap polyposis in a child: A rare cause of rectal bleeding

S Arulprakash, Tarun George, Malathi Sathiyasekaran
Department of Gastro Sciences, Advanced Endoscopy and Liver Diseases, MGM Health Care, Chennai, Tamil Nadu, India

Date of Submission	06-Aug-2020
Date of Acceptance	02-Sep-2020
Date of Web Publication	04-Dec-2020

Correspondence Address:
S Arulprakash
2033, Block 2, Osian Chlorophyll, Porur, Chennai - 600 116, Tamil Nadu
India

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/ghep.ghep_6_20

Abstract

Inflammatory cap polyposis (CP) is a uncommon, non-malignant condition characterized by the presence of sessile and pedunculated polyps in the colon and rectum. The histology of these polyps reveals a “cap” of inflammatory granulation tissue with fibrinopurulent exudate that covers the polyps, hence the name “inflammatory cap polyposis”. The pathogenesis of this non-malignant condition is poorly understood and while several associations have been made, causality has yet to be elucidated. The mainstay of initial treatment is conservative, however complicated and refractory cases usually benefit from endoscopic or surgical intervention followed by close surveillance for disease recurrence and progression. We present a 12 yr old girl with a large cap polyposis which was resected successfully by EMR and literature review.

Keywords: Cap polyposis, endoscopic mucosal resection, rectal bleeding

How to cite this article:
Arulprakash S, George T, Sathiyasekaran M. Cap polyposis in a child: A rare cause of rectal bleeding. Gastroenterol Hepatol Endosc Pract 2021;1:34-6

How to cite this URL:
Arulprakash S, George T, Sathiyasekaran M. Cap polyposis in a child: A rare cause of rectal bleeding. Gastroenterol Hepatol Endosc Pract [serial online] 2021 [cited 2021 Apr 22];1:34-6. Available from: http://www.ghepjournal.com/text.asp?2021/1/1/34/302221

Introduction

Inflammatory cap polyposis (CP) is a rare, non-malignant condition characterized by the presence of sessile and pedunculated polyps in the colon and rectum. The histology of these polyps reveals a “cap” of inflammatory granulation tissue with fibrinopurulent exudate that covers the polyps, hence the name “inflammatory cap polyposis”. The pathogenesis of this non-malignant condition is poorly understood and while several associations have been discussed in literature. The mainstay of initial treatment is conservative, however complicated and refractory cases usually benefit from prompt surgical intervention followed by close surveillance for disease recurrence and progression.

Case Report

A 12-year-old girl presented with passage of blood and mucus per rectum for 10 months. There was a history of mass descending per rectum and straining. She had a constant urge to defecate, but passed only mucous mixed or tinged with blood 10–15 times per day. She also had vague lower abdominal pain. There were no history of digital evacuation, surgery, fever, pedal edema, and weight loss and no family history of inflammatory bowel disease or colonic malignancy. She had not attained menarche, and her school performance was average. On examination, she was of average build and did not look unwell. There was no significant finding apart from mild pallor. The abdomen was soft and no mass was palpable. The perianal area was normal; there was no fissure or fistula, but a fleshy mass was palpable on rectal examination. Complete blood counts were normal except hemoglobin of 9.1 g/dL. Erythrocyte sedimentation rate was 24 mm/h and C-reactive protein was <6 mg/dL. Total protein was 6.8 g/dL, albumin was 3.2 g/dL, and all other parameters were normal. Colonoscopy showed multiple, polypoidal lesions of varying size. Four were about 1.5 cm in size and 10–12 were smaller <10 mm, all coalescing at the base. A few satellite sessile polyps 5–6 in number and 8–10 mm in size were also seen. The lesions covered a mucosal area of 4.5 cm × 3.5 cm, encircling three-fourth of the rectal lumen about 4 cm from the anal verge [Figure 1]. Contrast-enhanced computed tomography abdomen reported a soft-tissue density mass measuring 4.3 cm × 4.0 cm × 4.8 cm involving the lower rectum. There was no wall thickening or lymph node enlargement [Figure 2]. Endoscopic mucosal resection of the polypoidal lesions was done [Figure 3]. Histopathological examination showed a cap of inflammatory granulation tissue, with fibrinopurulent exudate covering the polyp with tortuous glands and mixed inflammatory cell infiltrate within the lamina propria [Figure 4]. The endoscopic and histologic features were characteristic of cap polyposis (CP). Upper gastrointestinal endoscopy was not done. The patient’s symptoms regressed, and, on follow-up after 6 months, she was asymptomatic. This case is being presented because of its rarity and the unique features which assist in diagnosis.

Figure 1: Colonoscopy showing the polypoidal multilobulated lesion covered with glistening mucoid secretions

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Figure 2: Contrast-enhanced computed tomography abdomen showing a soft-tissue density mass measuring 4.3 cm × 4.0 cm × 4 cm in the lower rectum. There is no wall thickening or lymph node enlargement

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Figure 3: Colonoscopy image postendoscopic mucosal resection

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Figure 4: Histopathological image of cap polyposis: low-power and high-power fields showing the cap of inflammatory granulation tissue with fibrinopurulent exudate covering the polyp, as well as an infiltrate of mixed inflammatory cells within the lamina propria

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Discussion

CP is a rare benign, inflammatory, nonmalignant condition of the colon with distinct clinical, endoscopic, and histology features. Although Williams et al.^[1] described this entity 35 years ago, it is still an underdiagnosed and misdiagnosed condition. CP usually occurs in the fifth decade of life and is very rare in children.^[2] A total of about 16 cases^[3],[4] have been reported in children and adolescents, with the youngest being 11 months of age.^[5] Male predominance has been noted in pediatrics, however in adults, it is more often seen in females. The common symptoms of CP are bloody mucoid stools, bleeding per rectum, straining, tenesmus, lower abdominal pain, and constipation. Weight loss and protein-losing enteropathy are uncommon symptoms. Endoscopically, the lesions are red; sessile; semi-pedunculated or polypoidal; varying from few mm to 7 cm in size; solitary or even up to 100 in number; and situated predominantly on the apices of the mucosal folds and covered by a thick layer of fibrinopurulent exudate. Majority of CP are seen in the rectum or rectosigmoid region with normal intervening mucosa between the polyps but occasionally may be identified elsewhere in the colon and rarely even in the stomach.^[6] The differential diagnosis based on the clinical and endoscopic features includes solitary rectal ulcer syndrome – polypoidal type, inflammatory bowel disease, pseudomembranous colitis, juvenile polyps, and colonic malignancy.^[7] The characteristic histopathological features of CP are elongated, distended, serpiginous crypts which become attenuated toward the mucosal surface; mixed inflammatory cells in the lamina propria, with a cap of granulation tissue; and thick fibrinopurulent exudate contributing to the apt title “cap polyposis.”^[2] The classic clinical, endoscopic, and histological features were seen in this child. These polyps secrete large amounts of nonsulfated mucins that are different from the mucus secreted by normal colorectal glandular cells. The adhesion of this mucus layer to the underlying epithelium is mediated by a close continuity with the mucus of goblet cells, and not by adhesion to the cytoplasmic membrane of epithelial cells.^[8] The pathogenesis of CP is poorly understood, but the most well-accepted hypothesis is colonic dysmotility with abnormal straining during defecation, initiating trauma to the mucosa, similar to the findings in mucosal prolapse syndrome or solitary rectal ulcer syndrome. Helicobacter pylori infection has also been postulated though H. pylori has not been isolated in CP. Various mechanisms such as release of inflammatory mediators, molecular mimicry, and a systemic immune response, have been attributed to this extragastric manifestation of H. pylori. Local inflammation, a probable etiology, was considered when CP was reported on an anastomotic site. Role of tumor necrosis factor-a and low expression of the mucin gene MUC3 have been described in CP.^[9] Recently, gut dysbiosis has been documented in CP, supporting the hypothesis that impaired host–bacterial mutualism underlies the pathogenesis of CP.^[10] Although in the majority the disease is chronic and unremitting, spontaneous regression has been reported. There are no reports of malignant transformation of CP. Because the pathogenesis is still not definite, various therapies have been advocated. The conservative measures include high-fiber diet, bowel training, and avoiding constipation and straining. This child was advised regarding diet, regular defecation pattern, and avoidance of straining. Medical therapy including H. pylori eradication, steroids, metronidazole, antibiotics, aminosalicylates, and infliximab^[9] has shown varying results and cannot be recommended universally. When CP presents with disturbing symptoms or prolapsing per rectum or occluding the lumen, it may be necessary to endoscopically or surgically remove the polyps. In this child, symptom-alleviating complete endoscopic mucosal resection of the lesion was done with excellent results. Surgical intervention should be done in medically refractory cases or in those patients with polyp recurrence. Because recurrence is possible in the presence of multiple polyps, it is essential to keep these patients on follow-up.^[11] This child on follow-up 6 months later is symptom free.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient’s guardian has given consent for images and other clinical information to be reported in the journal. The patient’s guardian understands that names and initials will not be published, and due efforts will be made to conceal patient identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

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