What are the causes of acute upper abdominal pain?

Causes of Acute Upper Abdominal Pain

Acute upper abdominal pain has multiple etiologies, with biliary disease (particularly acute cholecystitis from gallstones) being the most common cause requiring imaging evaluation, followed by pancreatitis, peptic ulcer disease, hepatic pathology, and critical extra-abdominal causes like myocardial infarction that must be excluded first 1, 2, 3.

Primary Gastrointestinal Causes

Biliary Tract Disease

• Acute cholecystitis is the leading surgical cause and most frequent complication of gallstone disease 4, 2, 5
• Cholelithiasis (gallstones without inflammation)
• Ascending cholangitis
• Biliary colic from cystic duct obstruction

Pancreatic Disease

• Acute pancreatitis is among the most common gastrointestinal disorders requiring hospitalization 6
  • Main causes: gallstones and alcohol use
  • Presents with upper abdominal pain radiating to the back, worse with eating
  • Diagnosis requires 2 of 3 criteria: characteristic pain, lipase/amylase >3× normal, imaging findings consistent with pancreatitis 6

Gastroduodenal Disease

• Peptic ulcer disease (gastric and duodenal ulcers)
• Gastritis
• Gastric cancer
• Gastroesophageal reflux disease (GERD)
• Esophagitis 1

Hepatic Causes

• Liver abscess
• Hepatitis
• Painful liver neoplasms
• Hepatic congestion 2, 7

Critical Extra-Abdominal Causes (Cannot Miss)

Myocardial infarction must be excluded first in patients presenting with epigastric or upper abdominal pain 1. Other life-threatening non-GI causes include:

• Acute aortic syndromes (dissection, rupture)
• Pulmonary embolism
• Pneumonia (lower lobe)
• Respiratory infections 3, 7

Musculoskeletal Causes

• Abdominal wall pain
• Musculoskeletal strain 2, 3

Less Common but Important Causes

• Small bowel obstruction (including rare causes like bezoars, particularly in diabetic patients) 8
• Mesenteric ischemia
• Hiatal hernia 1

Location-Specific Differential

Right Upper Quadrant Pain

The differential is dominated by:

1. Acute cholecystitis (most common)
2. Hepatic pathology
3. Duodenal ulcer
4. Right lower lobe pneumonia
5. Renal/ureteral pathology 4, 2, 7

Epigastric Pain

Consider broader differential including:

1. Pancreatitis
2. Peptic ulcer disease
3. Gastritis
4. Myocardial infarction (critical to exclude)
5. Aortic pathology 1

Clinical Pearls

In patients with diabetes presenting with acute abdominal pain, consider diabetic ketoacidosis as a contributing or primary cause, which may coexist with mechanical causes like obstruction 8.

Gastroenteritis and nonspecific abdominal pain are actually the most common overall causes of acute abdominal pain, but specific surgical causes like cholecystitis, appendicitis, and diverticulitis require prompt identification 3.

The key is recognizing that while gallstone-related disease dominates the right upper quadrant differential, a systematic approach must exclude life-threatening cardiovascular and vascular causes first, then proceed through hepatobiliary, pancreatic, gastroduodenal, and other etiologies based on pain location and associated symptoms 1, 2, 3.