Tu1569 SMALL BOWEL ENDOSOCPY IN CHRONIC GRANULOMATOUS DISEASE-ASSOCIATED INFLAMMATORY BOWEL DISEASE

Abstract

Chronic granulomatous disease (CGD) is a rare immunodeficiency caused by genetic mutations of the NADPH oxidase complex. Dysregulated inflammation of the gastrointestinal (GI) tract leads to CGD-associated inflammatory bowel disease (IBD). Although lower GI tract involvement is the major target of study and therapy, characterization of small bowel disease is scarce and the appropriate modality to diagnose small bowel disease in CGD is unknown. To characterize small bowel disease and evaluate the clinical utility of wireless video capsule endoscopy (VCE) for the diagnosis of small bowel disease in CGD-associated IBD. Patients with genetically confirmed CGD were evaluated for IBD as a part of routine care in an ongoing natural history study from 2010 to present. Based on clinical evaluation, patients underwent radiologic, endoscopic, and/or small bowel evaluation with VCE (PillCam SB3, Medtronic©) when indicated. VCE was performed after at least eight hours of fasting. Anthropometric and laboratory data were analyzed and same-admission radiologic, endoscopic, and VCE findings were compared for their ability to identify and characterize small bowel disease. Thirty patients were evaluated with 18 excluded due to high VCE retention risk. Of the 12 patients with VCE, 67% were male, the median age was 19.5 years old (IQR 8), 75% were white, 17% were mixed race, and 8% were Asian. Patients had p47phox (58%) or gp91phox (42%) genetic mutations. VCE indications included abdominal pain (83%), diarrhea (67%), hematochezia (42%), iron deficiency anemia (8%), and/or elevated C-reactive protein level (CRP; 8%). Of those with imaging (n=11), one showed terminal ileum dilatation whereas the rest were normal. All patients underwent upper endoscopy (EGD) with duodenal erythema (25%), erosions (17%), nodularity (17%), friability (8%), or congestion (8%). Of those who underwent ileoscopy or colonoscopy (n=9), small bowel/terminal ileum findings included erosions (22%), ulcers (11%), and dilatation (11%). All VCEs were abnormal with small bowel findings of erosions (83%), inflammatory changes (erythema, edema, and granularity; 83%), ulcerations (75%), and blood/hematin (50%). Both patients without abdominal pain had disease on VCE, as did all three patients without anemia and all three patients without elevated CRP. Of those with EGD, VCE, and colonoscopy evaluation (n=11), disease was seen in all three modalities in 72.7%, VCE and colonoscopy only in 18.2%, or EGD and VCE only in 9.1%. CGD patients with GI symptoms often have active small bowel disease. In such patients, small bowel disease should be investigated, and therapy should seek to address any small bowel involvement. These interim results support continued exploration and characterization of small bowel disease in CGD and its optimal diagnostic modality.