What is the appropriate management for a pregnant patient presenting with right upper quadrant (RUQ) pain?

Management of Pregnant Patients with Right Upper Quadrant Pain

Begin immediately with ultrasound of the abdomen as your first-line imaging study for any pregnant patient presenting with RUQ pain, followed by MRI without IV contrast if ultrasound is non-diagnostic, and reserve CT only for life-threatening situations where maternal survival is at risk. 1

Initial Clinical Assessment

Evaluate vital signs with particular attention to:

• Fever, tachycardia, and tachypnea — this combination indicates serious complications requiring immediate attention 1
• Signs of hemodynamic instability or sepsis, which warrant immediate escalation 1

Consider the full differential diagnosis including:

• Acute cholecystitis (most common diagnosable cause of RUQ pain) 1
• Biliary disease including choledocholithiasis and acute cholangitis 1
• Appendicitis (can present atypically in pregnancy) 1
• Urolithiasis and pyelonephritis 1
• Pancreatitis 1
• Ovarian torsion 1
• Obstetric complications including HELLP syndrome and preeclampsia 1

Imaging Algorithm

Step 1: Ultrasound (Mandatory First-Line)

Ultrasound abdomen is the primary imaging modality with several key advantages 1:

• No radiation exposure to the fetus 1
• 96% accuracy for detecting gallstones 1
• Identifies gallbladder wall thickening, pericholecystic fluid, and sonographic Murphy sign 1
• Can diagnose most common causes and identify alternative diagnoses 1

For suspected acute cholecystitis, look for 1:

• Gallstones
• Gallbladder wall thickening >3mm
• Pericholecystic fluid
• Sonographic Murphy sign (88% sensitivity, 80% specificity)

For suspected acute cholangitis, look for 1:

• Clinical triad: jaundice, fever, and RUQ pain
• Biliary dilatation on ultrasound
• Evidence of obstruction (stone, stricture, mass)

Step 2: MRI Without IV Contrast (If Ultrasound Non-Diagnostic)

If ultrasound is equivocal or non-diagnostic, proceed immediately to MRI abdomen without IV contrast 1:

• Avoids ionizing radiation to the fetus 1
• Provides excellent soft tissue characterization 1
• MRCP can better visualize the biliary tree and surrounding structures 1

Step 3: CT Imaging (Reserved for Life-Threatening Situations)

CT should only be used when 1:

• MRI is unavailable or non-diagnostic
• The clinical situation is life-threatening
• Maternal survival takes absolute priority — do not withhold necessary CT if maternal health is at risk 1

Critical Management Pitfalls to Avoid

Do not delay imaging or treatment in pregnant patients with suspected acute cholecystitis or cholangitis 1:

• Complications including perforation carry significant maternal and fetal morbidity and mortality 1
• Maternal health takes absolute priority over radiation concerns in life-threatening situations 1

Do not assume musculoskeletal pain without imaging — atypical presentations can occur, and serious pathology may present with seemingly benign initial findings 2

When to Escalate Care Immediately

Obtain immediate surgical consultation for 1:

• Confirmed acute cholecystitis with complications (perforation, abscess, emphysematous cholecystitis)
• Acute cholangitis requiring biliary decompression
• Hemodynamic instability with severe pain
• Any surgical emergency identified on imaging

Consider HIDA scan (97% sensitivity, 90% specificity) if ultrasound is equivocal for cholecystitis and MRI is unavailable 1