Kjhd

RESIDENTS’ CLINIC RESIDENTS’ CLINIC

62-Year-Old Man With Weight Loss and Abdominal Pain
NISHA K. LASSI, MD*; NANDAN S. ANAVEKAR, MBBCH†; AND CONOR G. LOFTUS, MD‡

A

62-year-old man presented to Mayo Clinic Rochester with a history of steady weight loss during the previous 16 months and worsening weakness during the past 3. He was admitted to the hospital gastroenterology service with adiagnosis of “weight loss and abdominal distention.” Notably, he had undergone an abdominoperineal resection followed by chemoradiation for rectal cancer 2 years before presentation. At presentation, his symptom complex was remarkable for abdominal distention and diffuse, nonradiating, and continuous pain. The pain was notably exacerbated by eating, and he stated that within 3 to 4 hours after ameal he would have generalized cramps throughout the abdomen. The patient had an end colostomy from his surgical intervention, and he stated that, because of increased output from the stoma, he was changing his colostomy appliance over 6 times a day instead of his usual 1 to 2 times. He had no nausea or vomiting, fevers, or chills but did have a 16 kg weight loss during the 3 months beforeadmission. His medical history was remarkable for type 2 diabetes mellitus, the stated rectal cancer, and a previous cholecystectomy. The patient was a current smoker with a 50 pack-year smoking history. 1. Which one of the following is the most likely etiology of this patient’s symptom complex? a. Paralytic ileus b. Partial small bowel obstruction c. Acute gastroenteritis d. Malabsorption secondary toradiation enteritis e. Dumping syndrome A paralytic ileus is in the differential diagnosis for this presentation, but lack of other causative conditions for paralytic ileus such as pancreatitis or peritonitis makes this diagnosis unlikely. Additionally, before paralytic ileus is assumed, a mechanical obstructive process needs to be excluded because the management strategies for these 2 distinctpathophysiologic processes are different. At the time of presentation, the patient’s symptoms had been progressive over several months, were associated with postprandial pain and cramping, and occurred after surgery for rectal carcinoma. Given such a history, partial small bowel obstruction would be the most likely cause of his symptom complex. Gastroenteritis is unlikely in this setting because thepatient had no history of such a syndrome. Additionally, the cyclical nature of his pain complex and the exacerbation by food points more toward an obstructive process than acute infectious gastroenteritis. Malabsorption is also
Mayo Clin Proc. •

not a likely etiology for this patient’s presentation because his surgery involved large bowel resection; most absorptive processes occur in the smallbowel, which was left intact in this patient. However, his history of radiotherapy compels a consideration of radiation enteritis, and, given the lapse in time between his original treatment for rectal cancer and his presentation to our institution, chronic radiation enteritis is a possibility. Its physiologic consequences can include altered intestinal transit, reduced bile acid absorption,increased intestinal permeability, bacterial overgrowth, and malabsorption. The resulting clinical manifestations include nausea, vomiting, lactose intolerance, obstructive symptoms, diarrhea, weight loss, malnutrition, and bleeding (usually in patients with colonic involvement).1 Although malabsorption may have contributed to the patient’s condition at presentation, his primary underlying problem wasobstruction. Dumping syndrome2 is also unlikely given the lack of vasomotor symptoms. Defined as the poorly regulated dumping of gastric contents into the small intestine, dumping syndrome is often associated with a pylorus rendered incompetent by surgery. Since our patient had no surgery that manipulated the structure or innervation of the stomach, dumping syndrome is highly unlikely. On...