Gastroenterology clinical image challenge: A 74-year-old man was admitted to another hospital with a chief complaint of vomiting, fever and cough. He was diagnosed with aspiration pneumonia caused by ileus diagnosed with a computed tomography (CT) scan and esophagogastroduodenoscopy, which improved with fasting and antibiotic treatment. He had a history of hypertension, diabetes mellitus, angina pectoris, chronic hepatitis owing to hepatitis C virus, bilateral renal cysts and no prior abdominal surgeries; however, he had a gradually growing abdominal aortic aneurysm (AAA) 60 mm in diameter for two years, which was scheduled to be operated. Doctors in the other hospital suspected an obstruction located in an upper intestinal lesion and malrotation from the CT examination; therefore, to examine the cause of ileus, he was referred to our hospital and kept under a fasting condition.
On admission, he was afebrile and hemodynamically stable, and his abdomen was slightly distended without tenderness. Laboratory examinations revealed a slight elevation of serum hepatobiliary enzymes and creatinine without elevation of tumor markers as follows: alanine aminotransferase of 55 IU/L (normal range, 8–42 IU/L), γ-glutamyl transpeptidase of 105 IU/L (normal range, 13–64 IU/L) and creatinine of 1.21 mg/dL (normal range, 0.65-1.07 mg/dL). Magnetic resonance imaging (MRI) in our hospital showed malrotation of the small intestine on the right side of the abdomen and the colon on the left, and the ileum crossing the midline from the right to left, to enter the cecum. Single-balloon endoscopy showed that the second portion of the duodenum was normal; however, the third portion of the duodenum was not normally formed in spite of the absence of tumor) and the contrast dye could pass through to the anal side; however, the operability of the endoscope was poor and deep insertion of the scope was impossible, possibly owing to the fixed and sharply bent duodenum. After injection of the contrast dye into the duodenum, we checked the CT image without using the intravenous contrast dye injection and formed the 3D image of the small intestine, which clearly showed the stenotic area (Figure).
Why did the patient with malrotation experience ileus for the first time in his 70s? What examination would be helpful to evaluate the intestinal motility of this patient with a high-risk AAA?