DIFFERENTIAL DIAGNOSIS 1.Colon Cancer 2.Colonic obstruction 3.Crohn’s Disease

PATIENTCOLON CACOLONIC POLYP Colonic Obstruction CD Change in bowel habits +++ (diarrhea or constipation +/- Constipation+++/- Blood streaked stool+++(rectal bleeding)/occ ult blood + +/- Wt.loss++++ Abdominal pain_+++ Abdomonal discomfort ++ Radiologic feature-Apple core deformity Collar buttonString sign

CROHN’S DISEASE

an idiopathic, chronic, transmural inflammatory process of the bowel that often leads to fibrosis and obstructive symptoms, which can affect any part of the gastrointestinal (GI) tract from the mouth to the anus

CROHN’S DISEASE Low-grade fever, prolonged diarrhea with abdominal pain, weight loss, and generalized fatigability crampy or steady right lower quadrant or periumbilical pain W/C precedes and may be partially relieved by defecation If the colon is involved, patients may report diffuse abdominal pain accompanied by mucus, blood, and pus in the stool

Crohn’s disease- string sign

Pathophysiology exact cause of Crohn disease remains unknown initial lesion starts as a focal inflammatory infiltrate around the crypts, followed by ulceration of superficial mucosa. Later, inflammatory cells invade the deep mucosal layers and, in that process, begin to organize into noncaseating granulomas. The granulomas extend through all layers of the intestinal wall and into the mesentery and the regional lymph nodes. Neutrophil infiltration into the crypts forms crypt abscesses, leading to destruction of the crypt and atrophy of the colon. Chronic damage may be seen in the form of villous blunting in the small intestine as well.

ULCERATIVE COLITIS

Ulcerative colitis (UC) is an idiopathic chronic inflammatory bowel disease limited to the colon

Clinical Manifestation Frequent episodes of rectal bleeding, with or without mucus The characteristic feature is blood in each bowel movement. Urgency and tenesmus Abdominal cramps Weight loss in severe cases

Imaging Studies Plain abdominal radiographs are a useful adjunct to imaging in cases of ulcerative colitis of acute onset. In severe cases, the images may show colonic dilatation, suggesting toxic megacolon; evidence of perforation; obstruction; or ileus. Radiographic imaging has an important role in the workup of patients with suspected IBD and in the differentiation of ulcerative colitis and Crohn disease. Because of its ability to depict fine mucosal detail, double-contrast barium enema examination is a valuable technique for diagnosing ulcerative colitis and Crohn disease, even in patients with early disease. Traditionally, barium enema examination has been the mainstay of radiologic investigation for suspected ulcerative colitis.

Imaging Studies A plain abdominal radiograph might show colonic dilatation in severe cases, suggesting toxic megacolon. Also, evidence of perforation, obstruction, or ileus can be observed. toxic megacolonileus

Plain radiographic findings The colon may appear shortened, with associated loss of colonic haustra may show massive colonic dilatation associated with an abnormal mucosal contour The dilatation is most pronounced in the transverse colon.

Barium Enema Before ulcers appear, mucosal edema has a fine, granular appearance ulcers first appear, the mucosa may have a fine, stippled appearance ulcers become established and confluent, the mucosa is replaced by granulation tissue on double-contrast enema examination, the characteristic appearance is coarsely granular

Barium Enema acute and subacute phases of the disease: the ulcers may acquire a variety of shapes: collar-button ulcers occur with undermining of the ulcers double-tracking ulcers are longitudinally orientated and are sometimes several centimeters long.