Differential Diagnosis for Left Upper Quadrant Pain

The following is a differential diagnosis for left upper quadrant pain, categorized for clarity and emphasis on critical conditions.

• Single Most Likely Diagnosis
  • Gastritis or peptic ulcer disease: This is often the most common cause of left upper quadrant pain due to the proximity of the stomach to this area. Symptoms such as burning pain, especially after eating, and relief with antacids support this diagnosis.
• Other Likely Diagnoses
  • Gastroesophageal reflux disease (GERD): Similar to gastritis, GERD can cause pain in the left upper quadrant due to the reflux of stomach acid into the esophagus.
  • Pancreatitis: Although pancreatitis typically causes mid-abdominal pain, it can radiate to the left upper quadrant, especially if the tail of the pancreas is involved.
  • Splenic infarction or rupture: Conditions affecting the spleen can cause severe left upper quadrant pain and are often associated with trauma or underlying diseases like sickle cell anemia.
  • Diverticulitis: While more commonly associated with left lower quadrant pain, diverticulitis can occasionally cause pain in the upper quadrants if the diverticula are located in the upper parts of the colon.
• Do Not Miss Diagnoses
  • Myocardial infarction: Although typically presenting with chest pain, myocardial infarctions can occasionally cause referred pain to the left upper quadrant, especially if the inferior wall of the heart is involved.
  • Pneumonia or pleurisy: Infections or inflammation of the lung or pleura can cause pain that is referred to the left upper quadrant, especially if the lower lobes are involved.
  • Aortic dissection: A life-threatening condition where the inner layer of the aorta tears, causing severe pain that can be referred to the back or abdominal quadrants.
  • Pulmonary embolism: Similar to pneumonia, a pulmonary embolism can cause referred pain to the left upper quadrant if the embolism is located in the lower lobes.
• Rare Diagnoses
  • Diaphragmatic hernia: A condition where part of the stomach or intestine bulges into the chest through a hole in the diaphragm, which can cause left upper quadrant pain.
  • Left upper quadrant tumors: Tumors of the stomach, pancreas, or spleen can cause pain in this area, though they are less common.
  • Intestinal obstruction: While more commonly causing mid-abdominal pain, an obstruction in the upper gastrointestinal tract can cause left upper quadrant pain.
  • Shingles (Herpes Zoster): Reactivation of the varicella-zoster virus can cause a painful rash in a dermatomal distribution, which can occasionally involve the left upper quadrant.