What is the diagnostic workup for a patient presenting with vomiting and right upper quadrant pain?

Diagnostic Workup for Vomiting and Right Upper Quadrant Pain

The diagnostic workup for vomiting and right upper quadrant pain should begin with abdominal ultrasonography as the first-line imaging test, followed by targeted laboratory testing and additional imaging based on clinical findings. 1, 2

Initial Assessment

History Components to Assess

• Pain characteristics: onset, duration, quality, severity, radiation (especially to right shoulder or back), and exacerbating/alleviating factors 2
• Associated symptoms: fever, nausea, vomiting, anorexia, jaundice, changes in bowel habits, or weight loss 2
• Medication history: all medications taken within 6 weeks of presentation 2
• Medical history: prior biliary disease, biliary surgery, liver disease 2
• Family history of biliary or liver disorders 2
• Alcohol intake 2

Physical Examination Components

• Vital signs: check for fever, tachycardia, or hypotension 2
• Abdominal examination: right upper quadrant tenderness 2
• Murphy's sign: pain with inspiration during palpation of the right upper quadrant (highly suggestive of acute cholecystitis) 2
• Assessment for hepatomegaly or splenomegaly 2
• Evaluation for abdominal distension, masses, or peritoneal signs 2

Laboratory Testing

• Complete blood count (CBC): to assess for leukocytosis indicating infection or inflammation 2
• Liver function tests: ALT, AST, alkaline phosphatase, GGT, and bilirubin to evaluate for hepatobiliary disease 2
• Pancreatic enzymes: amylase and lipase to rule out pancreatitis 2
• Pregnancy test: for all women of reproductive age 2

Imaging Algorithm

First-Line Imaging

• Abdominal ultrasonography: The American College of Radiology and American Academy of Family Physicians strongly recommend ultrasonography as the initial imaging modality for right upper quadrant pain 1, 2
  • High accuracy for diagnosing gallstones (96%) 2
  • Can identify gallbladder wall thickening, pericholecystic fluid, and sonographic Murphy sign 2
  • Readily available, can identify other potential causes of pain, and avoids radiation exposure 1

Second-Line Imaging (if ultrasound is negative or equivocal)

• Cholescintigraphy (HIDA scan):

  • Higher sensitivity (96%) and specificity (90%) than ultrasound (81% and 83%) for detecting acute cholecystitis 1
  • Particularly useful following inconclusive ultrasonography 1
  • Helpful for diagnosing partial biliary obstruction due to stones, biliary stricture, or sphincter of Oddi dysfunction 1

• CT abdomen with contrast media:

  • Useful when ultrasound findings are inconclusive 1
  • Can help guide surgical planning 1
  • May demonstrate findings of acute cholecystitis when ultrasound is negative 1
  • Not recommended as first-line imaging for suspected biliary causes 1

• MRI abdomen with MRCP:

  • Excellent for detection of cholelithiasis/choledocholithiasis (sensitivity 85-100%, specificity 90%) 1
  • Superior to CT for suspected biliary sources of right upper quadrant pain 1
  • Can distinguish acute from chronic cholecystitis based on signal characteristics 1
  • Useful for evaluating patients with equivocal ultrasound findings 1
  • Can visualize hepatic and biliary abnormalities not characterized on ultrasound 1

Clinical Pearls and Pitfalls

• Remember that right upper quadrant pain has a broad differential diagnosis beyond biliary disease, including hepatic, pancreatic, renal, gastrointestinal, and even pulmonary causes 3
• Over one-third of patients initially thought to have acute cholecystitis actually have right upper quadrant pain attributable to other causes 3
• Non-contrast abdominal CT has very limited value in this context 1
• Normal laboratory values do not exclude serious pathology; imaging studies may still be necessary based on clinical presentation 2
• Rare causes of right upper quadrant pain such as hepatic tumors or midgut volvulus should be considered when common diagnoses are ruled out 4, 5

Diagnostic Algorithm Summary

1. Obtain targeted history and physical examination
2. Order initial laboratory tests (CBC, liver function tests, pancreatic enzymes, pregnancy test if applicable)
3. Perform abdominal ultrasonography as first-line imaging
4. If ultrasound is inconclusive or negative but clinical suspicion remains high:
   • Consider cholescintigraphy for suspected acute cholecystitis
   • Consider MRI with MRCP for suspected biliary obstruction or to better characterize findings
   • Consider CT with contrast if non-biliary causes are suspected or for surgical planning