Diagnosing gastric carcinoma.

The clinical presentation of abdominal pain, fatigue, and fever represents a number of potential diagnoses. Differential diagnoses for these common signs and symptoms include appendicitis, cholecystitis, diverticulitis, gastritis, renal colic, and myocardial infarction. Presenting symptoms are more likely to represent a gastrointestinal etiology with the addition of melena, ranging from a simple gastritis to a gastrointestinal malignancy. This column will explore the diagnostic process for evaluating symptoms of abdominal pain, fatigue, fever, and melena in a 58-year-old man from the perspective of an oncology nurse practitioner. An algorithm for narrowing from a broad list of potential diagnoses at the patient’s initial presentation to the most probable diagnoses is described, and the clinical reasoning process for narrowing the list is discussed.