A 23-year-old woman comes to the office with her husband because of nausea, vomiting, and a 7-kg (15.4-lb) weight loss over the last 3 months. According to her husband, she seems "stressed out" about eating food and spends time researching her diet. The patient says, "Just after eating a couple bites, I feel like I've had Thanksgiving dinner. I get relief after throwing up, but I'm worried about my weight loss." She has had no changes in bowel movements. The patient's only medical condition is type 1 diabetes mellitus, diagnosed when she was age 5. She uses bolus-prandial insulin. BMI is 20 kg/m2. Temperature is 37 C (98.6 F), blood pressure is 104/70 mm Hg, pulse is 80/min, and respirations are 14/min. On examination, the abdomen is soft with active bowel sounds; there is no distension. The remainder of the examination demonstrates no abnormalities. Complete blood count, serum electrolytes, and serum TSH are normal. Her hemoglobin A1c is 8.3%. Which of the following is the most appropriate next step in management of this patient?
Gastroparesis | |
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This patient's nausea, postprandial fullness, fear of eating, and significant weight loss could be explained by an eating disorder. Anorexia would seem unlikely because she has a normal BMI (18.5 - 24.9 kg/m2) and she is concerned about her weight loss (anorexia involves an intense fear of weight gain). Bulimia nervosa involves binge eating (not present in this patient) followed by compensatory measures (eg, purging) and somewhat fits with her presentation. However, psychiatric disorders are usually a diagnosis of exclusion that is only made after underlying medical disorders have been ruled out.
Long-standing diabetes mellitus (especially type 1) is often complicated by autonomic neuropathy; therefore, this patient is at increased risk for gastroparesis. Gastroparesis typically results from disruption of neurologic signaling within the vagus nerve and the myenteric plexus. Common signs include postprandial emesis, early satiety, weight loss, and abdominal pain, and many patients develop food aversion (eg, restricting food intake) because eating exacerbates the symptoms. The diagnosis is best evaluated with a gastric-emptying scan and an investigation for mechanical obstruction (eg, upper endoscopy ± CT/MR enterography). Management options include dietary modification (eg, low fat, small and frequent meals) and gastric prokinetic agents (eg, metoclopramide, erythromycin).
(Choice A) ACTH stimulation testing can help diagnose primary adrenal insufficiency, a condition that causes vomiting and weight loss. Patients may have decreased appetite but would not be fearful of eating. In addition, fatigue (90%), hyperpigmentation (40-70%), and electrolyte abnormalities such as hyponatremia (70-80%) and hyperkalemia (30-40%) would be expected.
(Choice B) Cognitive-behavioral therapy (CBT) is commonly used in the management of eating disorders. However, an eating disorder is less likely in this patient, and CBT should not be initiated until a medical cause of her symptoms has been appropriately investigated.
(Choice D) Selective serotonin reuptake inhibitors can be used to treat major depressive disorder, generalized anxiety disorder, and some eating disorders. This patient's signs of psychosocial distress are most likely secondary to gastroparesis, which requires diagnosis and treatment.
Educational objective:
Long-standing diabetes mellitus (especially type 1) is a common cause of gastroparesis. Patients typically have postprandial vomiting, early satiety, weight loss, and abdominal pain, and many develop food aversion. The diagnosis is best evaluated with a gastric-emptying scan and an investigation for mechanical obstruction (eg, upper endoscopy ± CT/MR enterography).