Cap polyposis (CP) which relapsed after remission by avoiding straining at defecation, and was cured by Helicobacter pylori eradication therapy

Vascular Malformation and CAP Polyposis: A New Insight into Pathophysiology or Fortuitous Association?

INTRODUCTION

CAP polyposis is a benign colorectal process presenting with multiple colorectal polyps with a "CAP" of inflammatory granulation tissue whose etiology has remained largely unknown.

CASE

A 24-year-old male presented with a long-standing history of repeated multiple sessile colonic polyps over a period of 17 years.

RESULTS

The numerous polyps showed consistent histologic features of superficial erosion with a surface "CAP" of granulation tissue with minimal submucosa to evaluate over this period. A left hemicolectomy disclosed an extensive vascular malformation.

CONCLUSION

The underlying vascular malformation may have an etiologic correlation to the overlying CAP polyps in this patient. Future cases may benefit from an evaluation of the underlying submucosa for the presence of possible vascular malformation likely to be missed on superficial polypectomy.

Polypectomy for Recurrent Inflammatory Cap Polyposis Combined with Argon Plasma Coagulation

A 15-year-old adolescent boy presented with chronic constipation, difficulty in defecation, and episodic bloody stools. A rectal mass lesion was digitally palpated. Colonoscopy showed a large circumferential polypoid lesion of the mid-rectum. Snare polypectomy was performed, and histopathology confirmed a diagnosis of benign inflammatory cap polyposis. At 3-month follow-up, sigmoidoscopy showed multiple recurrences of polyps at the site of the previous rectal polypectomy, which were removed by combined hot snare polypectomy and argon plasma coagulation. At 1-year follow-up, the patient was symptom-free and had no more episodes of bloody stool. Follow-up sigmoidoscopy showed a post-polypectomy rectal mucosal scar without recurrent polypoid lesions.

Cap polyposis: A rare cause of rectal bleeding in children

AIM: To evaluate the clinicopathological features and treatment outcomes of cap polyposis in the pediatric population.

METHODS: All pediatric patients with histologically proven diagnosis of cap polyposis were identified from our endoscopy and histology database over a 12 year period from 2000-2012 at our tertiary pediatric center, KK Women’s and Children’s Hospital in Singapore. The case records of these patients were retrospectively reviewed. The demographics, clinical course, laboratory results, endoscopic and histopathological features, treatments, and outcomes were analyzed. The study protocol was approved by the hospital institutional review board. The histological slides were reviewed by a pediatric histopathologist to confirm the diagnosis of cap polyposis.

RESULTS: Eleven patients were diagnosed with cap polyposis. The median patient age was 13 years (range 5-17 years); the sample included 7 males and 4 females. All of the patients presented with bloody stools. Seven patients (63%) had constipation, while 4 patients (36%) had diarrhea. All of the patients underwent colonoscopy and polypectomies (excluding 1 patient who refused polypectomy). The macroscopic findings were of polypoid lesions covered by fibrinopurulent exudates with normal intervening mucosa. The rectum was the most common involvement site (n = 9, 82%), followed by the rectosigmoid colon (n = 3, 18%). Five (45%) patients had fewer than 5 polyps, and 6 patients (65%) had multiple polyps. Histological examination of these polyps showed surface ulcerations with a cap of fibrin inflammatory exudate. Four (80%) patients with fewer than 5 polyps had complete resolution of symptoms following the polypectomy. One patient who did not consent to the polypectomy had resolution of symptoms after being treated with sulphasalazine. All 6 patients with multiple polyps experienced recurrence of bloody stools on follow-up (mean = 28 mo).

CONCLUSION: Cap polyposis is a rare and under-recognised cause of rectal bleeding in children. Our study has characterized the disease phenotype and treatment outcomes in a pediatric cohort.

Cap polyposis mistaken for Crohn's disease: case report and review of literature

We report the case of a 19-year old male who presented with collapse and hypoglycemia associated with two weeks of frequent hard stools, abdominal pain relieved by defecation, postprandial vomiting and significant weight loss. Radiologically and endoscopically a diagnosis of Crohn's colitis was made and the patient was treated with steroids and immunosuppression. Following several hospital admissions treatment had to be escalated to include anti-TNF-α agents. Despite maximum therapy the patient continued to deteriorate symptomatically and biochemically with severe hypoalbuminemia and persistent anemia and a total colectomy was performed. Intra-operative finding was that of an inflamed large intestine and pseudo-polyposis but histology was reported as cap polyposis. The specimen was compared with the biopsies obtained from the earlier colonoscopies and it was felt that the previous samples were taken from areas of severely inflamed polypoid mucosa with histology mimicking colitis in inflammatory bowel disease.

Solitary rectal cap polyp: Case report and review of the literature

Rectal bleeding combined with the presence of a rectal mass has been traditionally associated with the presence of malignant disease. Cap polyposis is a relatively young and still undefined rare entity which mainly involves the rectosigmoid. It is characterized by the presence of inflammatory polyps. In this case report, we present a patient who was diagnosed with a solitary cap polyp of the rectum during the investigation of a bleeding rectal mass. The patient’s age and the absence of family history were not in favor of malignancy, despite the strong initial clinical impression. After confirmation of the diagnosis, the patient underwent a snare excision and remains asymptomatic. Cap polyposis, although rare, should be suspected and, when diagnosed, should be treated according to location, number of polyps and severity of symptoms.

Successful management of cap polyposis with eradication of Helicobacter pylori relapsing 15 years after remission on steroid therapy

A 37-year-old woman was evaluated at our hospital for a treatment-resistant proctosigmoiditis. Fifteen years previously, ulcerative colitis was suspected and she was cured by steroid therapy. Colonoscopy revealed multiple sessile polyps covered with white exudate from the rectum to the sigmoid colon. Histopathological examination revealed a mucosal surface cover of granulation tissue. Based on these findings, cap polyposis was diagnosed. She underwent Helicobacter pylori eradication therapy, and at 1 month after therapy, her symptoms had improved. We present a case of cap polyposis relapsing 15 years after remission with steroid therapy, and that was improved by H. pylori eradication therapy.