Management of Right Upper Quadrant Abdominal Pain
Obtain an abdominal ultrasound immediately after initial laboratory evaluation—this is the first-line imaging study with the highest appropriateness rating (9/9) and should never be skipped. 1
Initial Laboratory Workup
Before any imaging, obtain these specific tests:
- Complete blood count (CBC) to assess for leukocytosis indicating infection or inflammation 1
- Liver function tests (LFTs) to evaluate hepatobiliary disease 1
- Pancreatic enzymes (lipase/amylase) to rule out pancreatitis 1
- Pregnancy test for ALL females of reproductive age before any imaging to prevent unnecessary radiation exposure and identify ectopic pregnancy 1, 2
- Urinalysis to evaluate for renal stones or infection 1, 2
First-Line Imaging: Abdominal Ultrasound
Ultrasound is superior to CT as initial imaging because it provides excellent evaluation of gallbladder pathology, has no radiation exposure, is readily available, and can identify liver abnormalities and other causes of RUQ pain 1. The sensitivity for acute cholecystitis is 88%, though this means ultrasound can miss the diagnosis in 12% of cases 3.
Ultrasound should evaluate for:
- Gallstones and gallbladder wall thickening 3
- Pericholecystic fluid and sonographic Murphy's sign 3
- Bile duct dilatation 3
- Hepatic abnormalities 3
Critical Pitfall: CT has only 75% sensitivity for gallstones, so negative CT does not exclude cholelithiasis 3
When Ultrasound is Diagnostic
If ultrasound shows ≥2 findings of acute cholecystitis (gallbladder wall thickening, pericholecystic fluid, sonographic Murphy's sign, gallbladder distension, or sludge/stones) AND the patient has fever, leukocytosis, or persistent RUQ pain, do not delay surgical consultation while awaiting additional imaging 3.
Refer immediately to emergency department or acute surgical service if fever with leukocytosis suggests acute cholecystitis or cholangitis 3.
When Ultrasound is Negative or Equivocal
If ultrasound is negative but clinical suspicion remains high, the next step depends on what you suspect:
For Suspected Biliary Disease:
MRI with MRCP is superior to CT for biliary sources of RUQ pain, with sensitivity of 85-100% for cholelithiasis/choledocholithiasis 4, 1. MRI provides excellent visualization of the cystic duct and common bile duct, which is a significant advantage over ultrasound 4.
For Suspected Acute Cholecystitis with Equivocal Ultrasound:
Proceed to HIDA scan (96% sensitivity, 90% specificity) or CT with IV contrast to evaluate for complications 3. The HIDA scan is particularly useful for diagnosing biliary dyskinesia or hyperkinesia in patients with intermittent pain and normal ultrasound 5.
Critical Pitfall: Never order CT without IV contrast for suspected cholecystitis—critical findings like gallbladder wall enhancement and adjacent liver parenchymal hyperemia cannot be detected without contrast 3
For Suspected Complications:
If perforation, abscess, or gangrenous cholecystitis is suspected, obtain CT with IV contrast immediately 3. CT may reveal complications such as gangrene, gas formation, intraluminal hemorrhage, and perforation 4.
Special Considerations
Intermittent or Chronic Pain:
For low-grade, partial, or intermittent biliary obstruction presenting with recurrent RUQ pain, cholecystokinin-augmented HIDA scan can diagnose chronic gallbladder disease, partial biliary obstruction, and biliary dyskinesia 4. This test does not carry the risk of pancreatitis seen with manometric evaluation 4.
Pregnant Patients:
In pregnant patients with equivocal ultrasound, MRI is preferred over CT to avoid radiation exposure 3.
Critically Ill Patients:
Do not assume sludge alone equals cholecystitis—critically ill patients commonly have gallbladder abnormalities including sludge without true acute cholecystitis (acalculous cholecystitis) 3.
Imaging to Avoid
Conventional radiography (plain X-rays) has minimal diagnostic value for RUQ pain and should not be routinely ordered 1. Noncontrast abdominal CT has very limited value in this context 4.
"Can't Miss" Diagnoses to Consider
While evaluating RUQ pain, always consider these life-threatening conditions: