Su1254 Histological Recovery of Proximal Colon Is Incomplete in Patients With Endoscopically Long-Term Quiescent Ulcerative Colitis

Abstract

Context: Chronic abdominal pain and diarrhea carry a significant morbidity in the pediatric population and are frequently attributed to irritable bowel syndrome in the absence of inflammatory pathology. Mastocytic colitis is reported in adults but infrequently implicated in the pathology of children and adolescents with chronic abdominal pain or diarrhea. Objective: Describe cases of mastocytic colitis in children with chronic abdominal pain and diarrhea. Methods: We reviewed all cases of chronic diarrhea from 2010 to present from our large urban Pediatric GI practice of biopsy proven colonic mastocytosis (.20 mastocytes/ hpf with tryptase staining in .=5 slices) in the descending colon. Pathology was reexamined and cases with additional findings in the colon or small intestine excluded. The remaining 7 cases were reviewed for symptoms, allergies, diagnostic testing, pathology results, treatments, and additional diagnoses. Results: Age ranged 8-17 years; 6 female, 1 male. All cases except one male with spina bifida experienced abdominal pain (periumbilical, epigastric, right upper quadrant, or diffuse). 5 presented with vomiting, 4 with constipation, and 2 with reflux symptoms. Most had multiple missed school days. Blood work was performed and negative in patients for celiac serologies (4), CRP and ESR (4), thyroid studies (3), amylase and lipase (1), CBC (4) and CMP (4). Stool calprotectin was tested and elevated in one patient. Imaging included abdominal films showing fecal impaction (2). Treatments prior to diagnosis were antacids (5), polyethylene glycol (4), probiotics (1), and antispasmodics (2); 1 received an unknown antibiotic and 1 received albendazole without resolution of symptoms. Due to persistent symptoms, all underwent upper endoscopy and colonoscopy. Of these, 3 had evidence of reflux esophagitis. Biopsies of the small bowel were without pathology and biopsies of the colon showed mastocytosis only. All were started on a mastocyte stabilizer cromolyn; 3 on loratadine, 3 on ranitidine, and 1 on Entocort and rectal hydrocortisone. Additional diagnoses were constipation (4), lactase deficiency (2), GERD (3), NASH (1) and gastroparesis (1). Additional medications post-diagnosis were antacids (3), metoclopramide (1), and hyoscyamine (1). Allergy testing was performed in one and revealed environmental allergies. Of the 7 patients, 2 were diagnosed in sufficient time to exhibit response. Both showed improvement in symptoms with decreased abdominal pain and diarrhea frequency at 1 month with resolution by 22 months in one and improved abdominal pain at 1month in the other. Additional data continues to be collected. Conclusion: Mastocytosis of the colon may contribute to chronic abdominal pain and diarrhea in children and adolescents. This entity should be considered while ruling out additional inflammatory etiologies.