What is the appropriate evaluation and initial management for a new‑onset right upper‑quadrant abdominal pain in an adult?

Right Upper Quadrant Pain: Evaluation and Management

Initial Imaging: Ultrasound First

Obtain an abdominal ultrasound immediately as the first-line imaging study for any patient presenting with right upper quadrant pain. 1, 2

• Ultrasound is rated 9/9 (usually appropriate) by the American College of Radiology and has 96% accuracy for diagnosing gallstones 1, 2
• This modality avoids radiation exposure, is cost-effective, and provides rapid diagnosis to guide immediate clinical decisions 2
• Ultrasound identifies gallstones, gallbladder wall thickening, pericholecystic fluid, sonographic Murphy sign, bile duct dilatation, and hepatic abnormalities 1, 3
• Over one-third of patients with RUQ pain do not have acute cholecystitis, and ultrasound can identify alternative diagnoses across multiple organ systems 4, 5

Focused History and Physical Examination

Document specific pain characteristics and perform targeted physical examination maneuvers:

• Record pain onset, duration, quality, severity, and radiation pattern—biliary colic typically radiates to the right shoulder or back 1, 3
• Note fever, nausea, vomiting, jaundice, and changes in bowel habits 1, 3
• Obtain complete medication history from the past 6 weeks, including prescription drugs, over-the-counter medications, and herbal supplements 1, 3
• Document alcohol intake and any history of biliary disease, prior biliary surgery, or liver disease 1, 3
• Check vital signs for fever, tachycardia, or hypotension suggesting infection or sepsis 1, 3
• Elicit Murphy's sign (pain with inspiration during RUQ palpation), which is highly suggestive of acute cholecystitis 1, 3
• Examine for hepatomegaly, splenomegaly, abdominal distension, masses, or peritoneal signs 1, 3

Essential Laboratory Testing

Order the following laboratory studies concurrently with ultrasound:

• Complete blood count to assess for leukocytosis indicating infection or inflammation 1, 3
• Liver function tests including ALT, AST, alkaline phosphatase, GGT, and bilirubin 1, 3
• Pancreatic enzymes (amylase and lipase) to exclude pancreatitis 1, 3
• Pregnancy test for all women of reproductive age before any imaging to rule out ectopic pregnancy 1, 2

Imaging Algorithm When Ultrasound Is Equivocal

If ultrasound findings are negative or equivocal and clinical suspicion remains high, escalate imaging based on the clinical scenario:

For Suspected Acute Cholecystitis with Equivocal Ultrasound:

• Proceed to cholescintigraphy (HIDA scan), which demonstrates 96% sensitivity and 90% specificity for acute cholecystitis, outperforming ultrasound's 81% sensitivity and 83% specificity 2
• Alternatively, obtain CT abdomen with IV contrast to evaluate for complications such as perforation, abscess, gangrenous cholecystitis, gas formation, or intraluminal hemorrhage 6, 1

For Suspected Biliary Obstruction or Choledocholithiasis:

• Order MRI abdomen with MRCP, which has 85-100% sensitivity for cholelithiasis/choledocholithiasis and 90% specificity 6, 1
• MRCP is superior to CT for assessing suspected biliary sources of RUQ pain and provides comprehensive evaluation of the hepatobiliary system 6

For Atypical Presentations or Critically Ill Patients:

• Obtain CT abdomen with IV contrast (rated 6/9 by ACR) when the patient's presentation is atypical, ultrasound is nondiagnostic, or the patient is critically ill requiring comprehensive evaluation 2
• CT reveals complications and can identify alternative diagnoses when acute cholecystitis is not the cause 6

Critical Pitfalls to Avoid

Do not skip ultrasound and proceed directly to CT—ultrasound provides rapid, cost-effective diagnosis without radiation exposure and should always be performed first unless the patient is hemodynamically unstable 1, 2

Do not order CT without IV contrast for suspected cholecystitis—critical findings like gallbladder wall enhancement and adjacent liver parenchymal hyperemia cannot be detected without contrast 1, 2

Do not assume negative CT excludes gallstones—CT has only 75% sensitivity for gallstones, so negative CT does not rule out cholelithiasis 1, 2

Do not assume gallbladder sludge alone equals cholecystitis—critically ill patients commonly have gallbladder abnormalities including sludge without true acute cholecystitis; acute cholecystitis requires ≥2 ultrasound findings (wall thickening, pericholecystic fluid, sonographic Murphy sign, distension, or stones) plus clinical features (fever, leukocytosis, persistent pain) 2

Urgent Referral Indications

Refer immediately to the emergency department or acute surgical service if:

• Fever with leukocytosis suggesting acute cholecystitis or cholangitis is present 2
• Clinical triad of jaundice, fever/chills, and RUQ pain suggests acute cholangitis 2
• Imaging reveals perforation, abscess, or other complications requiring urgent intervention 2