Differential Diagnosis for Right Upper Quadrant Pain and Right Shoulder Pain

The combination of right upper quadrant pain and right shoulder pain can be caused by various conditions. Here's a categorized differential diagnosis:

• Single Most Likely Diagnosis

  • Gallbladder Disease (Cholecystitis or Cholelithiasis): The most common cause of right upper quadrant pain that can also refer pain to the right shoulder due to shared nerve roots (phrenic nerve). Gallstones can cause inflammation or obstruction of the gallbladder, leading to pain.

• Other Likely Diagnoses

  • Peptic Ulcer Disease: Ulcers in the stomach or duodenum can cause upper abdominal pain that may radiate to the right shoulder. The pain is often related to eating.
  • Hepatitis: Inflammation of the liver can cause right upper quadrant pain and may be accompanied by systemic symptoms like fever and jaundice.
  • Pyelonephritis or Kidney Stones: Infection or obstruction of the right kidney can cause flank pain that may radiate to the right upper quadrant and sometimes to the shoulder.
  • Pneumonia (Right Lower Lobe): Basilar pneumonias can cause referred pain to the abdomen and shoulder due to diaphragmatic irritation.

• Do Not Miss Diagnoses

  • Myocardial Infarction: Although less common, myocardial infarctions can present with atypical pain, including right shoulder pain. It's crucial to consider cardiac causes, especially in patients with risk factors.
  • Pulmonary Embolism: Can cause sudden onset of chest pain and shortness of breath, with possible referred pain to the shoulder.
  • Aortic Dissection: A life-threatening condition that can cause severe, tearing chest pain radiating to the back or abdomen.
  • Ruptured Hepatic or Splenic Artery Aneurysm: Although rare, these conditions can present with sudden onset of abdominal pain and can be life-threatening.

• Rare Diagnoses

  • Fitz-Hugh-Curtis Syndrome: A rare condition where pelvic inflammatory disease causes adhesions between the liver and abdominal wall, leading to right upper quadrant pain.
  • Diaphragmatic Hernia: Can cause abdominal contents to herniate into the thoracic cavity, leading to referred pain.
  • Intra-abdominal Malignancies: Tumors in the liver, gallbladder, or other nearby structures can cause chronic pain in the right upper quadrant and shoulder.

Each of these diagnoses has distinct characteristics and risk factors. A thorough history, physical examination, and diagnostic tests (such as imaging and laboratory studies) are essential for making an accurate diagnosis.