Correct answer: C
Rationale
This patient has long-standing diabetes with associated complications from prolonged hyperglycemia, with symptoms of delayed gastric emptying. The next best step would be to perform a gastric-emptying study or scintigraphy to confirm the diagnosis of diabetic gastroparesis. A dietitian consult will be necessary once gastroparesis is confirmed, since dietary modifications are the mainstay of treatment. Strict blood glucose control is necessary to prevent worsening gastrointestinal symptoms, and an evaluation by an endocrinologist is reasonable if gastroparesis is confirmed. A trial of metoclopramide may be necessary if gastroparesis symptoms are not controlled with dietary modifications, but it would not be first-line treatment in diabetic gastroparesis.
References
1. Camilleri M. Advances in diabetic gastroparesis. Rev Gastroenterol Disord. 2002;2:47-56.
2. Camilleri M, Vazquez-Roque MI. Gastric dysmotility at the organ level in gastroparesis. In: Parkman H, McCallum R. Gastroparesis: Pathophysiology, presentation, diagnosis, and treatment. New York: Springer; 2011. p. 37-46.