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
  • Porphyria: A group of disorders that can cause abdominal pain, among other symptoms, due to a buildup of natural chemicals that produce porphyrin in the body.
  • Lead Poisoning: Can cause abdominal pain, constipation, and other systemic symptoms.
  • Abdominal Migraine: A condition that causes recurrent episodes of severe abdominal pain, often accompanied by other migraine symptoms like headache and nausea.
  • Intussusception: A condition where a part of the intestine slides into an adjacent part, causing bowel obstruction and severe abdominal pain, more common in children but can occur in adults.

Each of these diagnoses has distinct characteristics and requires a thorough medical evaluation to determine the underlying cause of abdominal pain. The history, physical examination, and sometimes diagnostic tests are crucial in narrowing down the differential diagnosis.