Differential Diagnosis for Burping, Nausea, Severe Abdominal Pain, and Back Pain in an Elderly Patient

Single Most Likely Diagnosis

• Peptic Ulcer Disease (PUD): The symptoms of burping, nausea, severe abdominal pain, and weight loss are classic for peptic ulcer disease, especially in an elderly patient. The fact that the patient has a normal exam and normal blood work does not rule out PUD, as these can be present even with a normal physical examination and laboratory results.

Other Likely Diagnoses

• Gastroesophageal Reflux Disease (GERD): GERD can cause similar symptoms, including burping, nausea, and abdominal pain, and is common in the elderly population.
• Cholecystitis or Biliary Colic: Although the patient has normal blood work, which includes normal liver function tests and bilirubin, biliary disease can sometimes present with non-specific symptoms and normal initial labs.
• Pancreatitis: While pancreatitis typically presents with elevated pancreatic enzymes, it can sometimes have a more subtle presentation, especially in the elderly, with normal or only slightly elevated enzymes.

Do Not Miss Diagnoses

• Pancreatic Cancer: Given the weight loss and abdominal pain, pancreatic cancer must be considered, even though it is less likely. It is crucial to not miss this diagnosis due to its poor prognosis if left untreated.
• Mesenteric Ischemia: Although less common, mesenteric ischemia can present with severe abdominal pain out of proportion to physical examination findings and can have normal initial labs, making it a "do not miss" diagnosis.
• Elderly-Onset Inflammatory Bowel Disease (IBD): While less common in the elderly, IBD (Crohn's disease or ulcerative colitis) can present at any age and should be considered in the differential diagnosis of chronic abdominal symptoms.

Rare Diagnoses

• Zollinger-Ellison Syndrome: A rare cause of peptic ulcers due to excessive gastrin production, which could explain the severe symptoms.
• Abdominal Aortic Aneurysm: Although typically presents with back pain and a palpable abdominal mass, a leaking or ruptured aneurysm can cause severe abdominal and back pain and should be considered, especially in an elderly patient with risk factors.
• Gastric Cancer: While less common than other gastrointestinal issues, gastric cancer can present with non-specific symptoms such as weight loss, nausea, and abdominal pain, and should be considered, especially in the context of significant weight loss.