What is the workup for left upper quadrant pain in pregnancy?

Workup for Left Upper Quadrant Pain in Pregnancy

Ultrasound should be the first-line imaging modality for evaluating left upper quadrant pain in pregnant women, followed by MRI if ultrasound is inconclusive, with CT reserved only when MRI is unavailable. 1

Initial Diagnostic Approach

First-Line Imaging

• Transabdominal ultrasound: Should be directed at the area of maximal pain
  • Advantages: No radiation exposure, real-time imaging, can be directed to the area of pain
  • Diagnostic yield: Approximately 58% of cases 1
  • Target conditions: Splenic pathology, pancreatitis, gastric issues, renal conditions, and obstetric causes

Second-Line Imaging

• MRI without and with contrast: When ultrasound is inconclusive
  • Advantages: No radiation exposure, superior soft tissue contrast
  • High sensitivity (96.8%) and specificity (99.2%) for inflammatory conditions 1
  • Particularly useful for pancreatic, splenic, and other solid organ evaluation

Third-Line Imaging (Limited Use)

• Low-dose CT with oral contrast: Only when MRI is unavailable and diagnosis is urgent
  • Should be used judiciously due to radiation exposure to the fetus
  • Consider only after discussing risks with patient, obstetrician, and radiologist 2

Differential Diagnosis for LUQ Pain in Pregnancy

Gastrointestinal Causes

• Pancreatitis: Consider in upper abdominal pain with or without nausea/vomiting

  • Laboratory: Amylase, lipase, triglycerides, calcium levels
  • Imaging: Ultrasound to evaluate for gallstones (common cause in pregnancy) 3

• Splenic conditions: Infarction, abscess, or rupture

  • Ultrasound is first-line, MRI for inconclusive cases

Infectious Causes

• Shingles (Herpes zoster): Consider in cases of severe, dermatomal pain
  • May present before vesicular eruption, making diagnosis challenging
  • Careful skin examination for early vesicular eruptions in the T6-T10 dermatome 4

Musculoskeletal Causes

• Intercostal muscle strain/costochondritis:
  • Exacerbated by pregnancy-related postural changes
  • Physical examination: Localized tenderness, pain with movement 5

Other Conditions

• Intra-abdominal abscess: Consider in patients with fever and persistent pain

  • Ultrasound may miss deep abscesses
  • MRI should be considered before CT 2

• Echinococcal disease: Rare but should be considered in endemic areas

  • Ultrasound can identify cystic lesions in the liver 6

Special Considerations in Pregnancy

Anatomical Changes Affecting Presentation

• Displacement of abdominal organs by the gravid uterus can alter the typical location of pain
• Pregnant women may present with atypical symptoms due to these anatomical changes 1

Common Pitfalls to Avoid

• Delaying diagnosis by attributing symptoms to normal pregnancy
• Hesitating to use appropriate imaging when clinically indicated
• Delaying necessary intervention, which can increase maternal and fetal morbidity 1

Management Principles

• For pancreatitis: IV hydration, pain management, and monitoring
• For infectious causes: Appropriate antimicrobial therapy (e.g., valacyclovir for shingles)
• For musculoskeletal pain: Non-pharmacological approaches first (physical therapy, rest)
• For abscesses: Antibiotics covering gram-negative and anaerobic organisms; consider drainage if >3cm 1

Follow-Up

• Close monitoring of pregnant patients with LUQ pain
• Repeat imaging as clinically indicated
• Multidisciplinary approach involving obstetrics, gastroenterology, and surgery as needed

Remember that pregnant women with abdominal pain should receive thromboprophylaxis if hospitalized, and urgent intervention should not be delayed solely due to pregnancy when clinically indicated 1.