Differential Diagnosis for Abdominal Pain

Abdominal pain is a symptom that can be caused by a wide range of conditions, from mild to life-threatening. The differential diagnosis can be organized into the following categories:

• Single Most Likely Diagnosis
  • Gastroenteritis: This is often the most common cause of abdominal pain, especially if the pain is accompanied by symptoms like diarrhea, vomiting, and fever. It's usually caused by a viral or bacterial infection.
• Other Likely Diagnoses
  • Irritable Bowel Syndrome (IBS): A chronic condition characterized by abdominal pain, bloating, and changes in bowel movements. It's a common cause of abdominal pain in the absence of other alarming symptoms.
  • Constipation: Can cause significant abdominal pain, especially if it's severe or chronic.
  • Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can cause chronic abdominal pain, diarrhea, weight loss, and sometimes blood in the stool.
  • Peptic Ulcer Disease: Ulcers in the stomach or duodenum can cause abdominal pain, often described as burning or gnawing, and can be exacerbated by eating.
• Do Not Miss Diagnoses
  • Appendicitis: Although not the most common cause, appendicitis is a medical emergency that requires prompt surgical intervention. Symptoms can include severe abdominal pain, fever, and vomiting.
  • Ectopic Pregnancy: A pregnancy that develops outside the uterus can cause severe abdominal pain and is life-threatening if not treated promptly.
  • Ruptured Aortic Aneurysm: A sudden, severe abdominal pain can be a sign of a ruptured aortic aneurysm, which is immediately life-threatening.
  • Intestinal Obstruction: Can cause severe abdominal pain, vomiting, and constipation, and requires urgent medical attention.
  • Pancreatitis: Inflammation of the pancreas can cause severe abdominal pain, nausea, and vomiting, and can be life-threatening if not properly managed.
• Rare Diagnoses
  • Intussusception: A condition where a part of the intestine slides into an adjacent part, which can cause abdominal pain, vomiting, and blood in the stool. It's more common in children but can occur in adults.
  • Mesenteric Ischemia: A condition where the blood flow to the intestines is blocked, causing severe abdominal pain, and is more common in older adults.
  • Porphyrias: A group of rare genetic disorders that can cause abdominal pain, among other symptoms.
  • Lead Poisoning: Can cause abdominal pain, constipation, and other systemic symptoms, though it's relatively rare in adults without a clear exposure history.

Each of these diagnoses has a different set of risk factors, symptoms, and diagnostic approaches. A thorough medical history, physical examination, and appropriate diagnostic tests are crucial for making an accurate diagnosis and providing effective treatment.