Crohn disease (CD) has a propensity for involvement of the terminal ileum and colon but also can occur throughout the gastrointestinal tract. When it occurs in the esophagus, stomach, and duodenum, it presents challenges in diagnosis and management. The type of detailed assessment of the upper gastrointestinal (UGI) tract by endoscopy and histology that is now widely available suggests that asymptomatic synchronous UGI involvement occurs in 30% to 50% of patients with ileocolonic disease. UGI CD is most commonly found in the gastric antrum, duodenal bulb, and duodenal loop. Isolated, clinically significant esophageal CD is unusual and is the source of less than 2% of complaints in patients with CD. Symptomatic gastroduodenal strictures are also rare and are found in fewer than 4% of patients with CD. In patients with concomitant ileocolonic disease, treatment of UGI inflammation is often dictated by medical treatment for the primary site. In the presence of obstructive symptoms, endoscopic therapy or surgery is indicated.
Symptoms of upper GI CD depend on both the clinical nature and distribution of disease. The CD is most often stricturing, with penetrating disease uncommon. Dysphagia, odynophagia, and pyrosis suggest esophageal involvement. Weight loss may occur as a result of these symptoms or as a systemic manifestation of CD. Anorexia, epigastric pain, nausea, and dyspepsia raise the possibility of gastroduodenal involvement, whereas vomiting with weight loss or anemia suggests progression.
The most common symptom is the rapid development of painful dysphagia that leads to substantial weight loss resulting from restriction of oral intake. The absence of heartburn and regurgitation is an important point that weighs against the more common reflux esophagitis. Approximately half of the patients affected by Crohn-related esophagitis will have a history of involvement of other portions of the gastrointestinal tract. In advanced disease, symptoms of obstruction may be present as a result of fixed stenotic segments. Postprandial vomiting, abdominal distension, epigastric pain, and rapid weight loss are indicative of gastric outlet obstruction, and when diarrhea, abdominal pain, weight loss, and an abdominal mass occur, the diagnosis of internal fistulae should be considered. Fever, tenderness, and an underlying mass, sometimes with associated cutaneous sinus, suggest incipient fistulization.
The most well-known criteria for the diagnosis of gastroduodenal CD are those of Nugent and Roy, which are the presence of either:
A histologic finding of noncaseating granulomatous inflammation of the stomach or duodenum, with or without concomitant CD in the remaining gastrointestinal tract, and the absence of other systemic granulomatous disorders
Confirmed CD of the gastrointestinal tract and radiographic or endoscopic findings of diffuse inflammation of the stomach or duodenum consistent with CD
Most patients with gastroduodenal CD are asymptomatic. The most common symptom is epigastric abdominal pain, which is often postprandial, nonradiating, and usually relieved by the ingestion of food and antacids. Pronounced, continuous abdominal pain associated with nausea and vomiting suggests gastric outlet obstruction as a result of stricture. Other common symptoms include profound weight loss, nausea with or without vomiting, and anorexia. Gastrointestinal blood loss may be indirectly noted in patients with gastroduodenal CD, usually in the form of chronic anemia. Melena and hematemesis suggest more significant bleeding, but this finding is rare.
Investigations in Upper Gastrointestinal Crohn Disease
Endoscopy of the UGI tract with serial biopsies is the primary study for the evaluation of all patients with suspected CD involvement. Findings at endoscopy are generally nonspecific and may include hyperemia, friability, granularity, and nodular mucosal thickening. In advanced disease, strictures in the esophagus or duodenum can be visualized and graded by severity. Aphthous ulcers and serpiginous ulcerations are more common in patients with gastroduodenal disease than with esophageal involvement. Histologic studies have demonstrated the presence of classical granulomas in the UGI tract in up to 30% of patients who are newly diagnosed with CD. Focal acute gastritis or duodenitis that is negative for Helicobacter pylori is present in up to 40% of patients. However, before focal gastritis is attributed to CD, H. pylori infection should be excluded. The positive predictive value of focal gastritis for CD in the absence of H. pylori is 94%.
Contrast radiography of the UGI tract may reveal typical features of CD. Water-soluble contrast material may be used to investigate advanced strictures, with barium contrast providing enhanced mucosal definition. Cross-sectional imaging using computed tomographic (CT) or magnetic resonance (MR) enterography provides additional information in patients with complicated strictures or fistulae and allows complete imaging of the small bowel. MR enterography is as sensitive as CT enterography and is favored because it entails no radiation exposure. Patients may need multiple scans over their lifetime, considering the chronicity of CD. Signs suggestive of CD include segmental inflammation, mucosal cobblestoning, ulceration, luminal narrowing/stricture formation, or aphthous and intramural ulcers. When dynamic studies are used, reduced peristalsis and delayed gastric emptying may be detected. Fixed stenosis due to fibrotic strictures manifests as a “string sign” on contrast radiography and is associated with prestenotic dilatation. Fistulae originating from the small bowel or colon to the stomach or duodenum also may be seen. Esophageal CD tends to be confined to the distal half of the esophagus, where early radiographic findings include thickened mucosal folds, asymmetric irregularity of the esophageal wall, and aphthous ulcers. Similar mucosal abnormalities are observed in early gastroduodenal CD. The distribution of disease in this location usually presents as contiguous involvement of the distal stomach and proximal duodenum and sometimes as isolated proximal duodenal CD. For unknown reasons, isolated distal duodenal and proximal gastric CD is extremely unusual. Progression of the inflammatory process results in fibrosis with resultant obstruction. Tubular stenosis of the esophagus may develop as an end result of fissuring ulcers that deepen into the submucosa and muscularis propria. Similar findings are observed in the duodenum, with cobblestoning and fissuring ulcers that may lead to stenosis and obstruction.
A rare but classic radiographic finding is the funnel-shaped deformity of diseased antrum and duodenal bulb, known as the “ram’s horn” sign. A barium enema should be performed when a gastrocolic fistula is suspected, because this procedure is more sensitive than UGI radiography.