What is the appropriate evaluation, work‑up, and management for a patient presenting with right upper quadrant pain?

Right Upper Quadrant Pain: Evaluation and Management

Initial Imaging

Right upper quadrant ultrasound is the mandatory first-line imaging study for any patient presenting with RUQ pain, rated 9/9 (usually appropriate) by the American College of Radiology. 1

• Ultrasound achieves 81% sensitivity and 83% specificity for acute cholecystitis, with 96% accuracy for gallbladder pathology overall 1, 2
• This modality provides comprehensive evaluation without radiation exposure and can identify alternative diagnoses beyond biliary disease 1, 3
• The examination must specifically assess for: cholelithiasis and gallbladder wall thickening, bile duct dilatation or stones, pericholecystic fluid, hepatic parenchymal abnormalities, and Murphy's sign 1, 2

Essential Laboratory Testing

Obtain complete metabolic panel including liver enzymes (AST, ALT, alkaline phosphatase, GGT), total and direct bilirubin, and complete blood count alongside initial ultrasound. 4, 2

• Beta-hCG must be checked in all women of reproductive age before any imaging to avoid missing ectopic pregnancy 4
• If GGT is elevated, confirm hepatic origin by checking alkaline phosphatase or fractionating ALP, as GGT elevates earlier and persists longer than ALP in cholestatic disorders 2

Algorithmic Approach Based on Ultrasound Results

If Ultrasound Shows Acute Cholecystitis

Proceed directly to surgical consultation when diagnostic ultrasound findings confirm acute cholecystitis. 2

• Diagnostic features include gallstones, gallbladder wall thickening >3mm, pericholecystic fluid, and sonographic Murphy's sign 1

If Ultrasound is Equivocal for Acute Cholecystitis

Order Tc-99m cholescintigraphy (HIDA scan) as the next step, which achieves 96% sensitivity and 90% specificity for acute cholecystitis—superior to ultrasound. 1, 2

• Cholescintigraphy confirms cystic duct obstruction and should follow equivocal ultrasound findings 1
• For suspected chronic cholecystitis or biliary dyskinesia, cholecystokinin-augmented cholescintigraphy with gallbladder ejection fraction calculation may be performed 1, 2

If Ultrasound is Negative or Shows Alternative Pathology

Obtain CT abdomen/pelvis with IV contrast when ultrasound is negative or non-diagnostic, as CT can identify complications and alternative diagnoses with >95% sensitivity for non-biliary pathology. 1, 4

• CT is particularly valuable for detecting complications of acute cholecystitis including gangrene, perforation, gas formation, and intraluminal hemorrhage 1
• CT helps guide surgical planning, as absence of gallbladder wall enhancement or stone in the infundibulum predicts conversion from laparoscopic to open cholecystectomy 1

If Biliary Obstruction or Ductal Pathology is Suspected

MRCP (MRI with magnetic resonance cholangiopancreatography) is the next diagnostic step when biliary obstruction is suspected but ultrasound is inconclusive, achieving 85-100% sensitivity and 90% specificity for choledocholithiasis. 5

• MRCP is superior to CT for evaluating biliary sources of RUQ pain, providing comprehensive visualization of the entire hepatobiliary system 5
• MRI demonstrates findings distinguishing acute from chronic cholecystitis: chronic shows low T2 signal intensity from fibrosis, while acute shows T2 hyperintensity from edema 1
• MRCP excels at detecting bile duct injuries, strictures, anatomic abnormalities, and visualizing the cystic duct remnant—advantages over ultrasound 1, 5

Critical Pitfalls to Avoid

Never skip ultrasound and proceed directly to CT or MRI unless the patient is hemodynamically unstable. 4, 2

• CT has only ~75% sensitivity for gallstones and exposes patients to unnecessary radiation when ultrasound is more diagnostic 2
• More than one-third of patients with acute RUQ pain do not have acute cholecystitis, making comprehensive ultrasound evaluation essential 6, 7

Do not assume all RUQ pain is biliary—ultrasound routinely visualizes hepatic, pancreatic, renal, adrenal, vascular, and gastrointestinal pathology that may cause RUQ pain. 7

• Alternative diagnoses identifiable on RUQ ultrasound include hepatic abscess, hepatocellular carcinoma, pancreatitis, renal colic, pyelonephritis, pneumonia, and bowel obstruction 7, 8

Recognize that pain specifically triggered by bowel movements or Valsalva suggests colonic or mechanical causes (hepatic flexure pathology, splenic flexure syndrome) rather than primary hepatobiliary disease, which typically presents with postprandial pain. 4

Special Considerations for Post-Cholecystectomy Patients

In post-cholecystectomy patients with new colicky RUQ pain radiating to the back, ultrasound remains first-line to evaluate for retained common bile duct stones, bile duct injury, or biloma. 5

• Choledocholithiasis occurs in 5-15% of post-cholecystectomy patients 5
• If ultrasound is normal in post-cholecystectomy chronic RUQ pain, MRCP is the next diagnostic step due to superior accuracy for detecting biliary causes including strictures and sphincter of Oddi dysfunction 5