How is chronic left upper quadrant abdominal pain managed in pediatrics?

Management of Chronic Left Upper Quadrant Abdominal Pain in Pediatrics

In pediatric patients with chronic left upper quadrant (LUQ) abdominal pain, ultrasound should be the initial imaging modality, and extensive diagnostic testing beyond history and physical examination rarely changes outcomes or identifies clinically significant organic disease. 1, 2

Initial Diagnostic Approach

Clinical Evaluation

• Focus on age-specific considerations, as the differential diagnosis varies significantly by age group 3
• Document pain characteristics including onset, duration, chronicity, associated symptoms (fever, vomiting, weight loss, bloody stools), and any trauma history 4, 3
• Perform detailed physical examination looking specifically for:
  • Localized tenderness versus diffuse pain
  • Signs of peritoneal irritation
  • Organomegaly (particularly splenomegaly in LUQ pain)
  • Referred shoulder pain (Kehr's sign suggesting splenic pathology) 5

Laboratory Testing

• Obtain complete blood count (CBC) to assess for leukocytosis indicating infection or inflammation 1, 6
• Urinalysis to exclude urinary tract infection or nephrolithiasis 1, 7
• Consider C-reactive protein if available to assess inflammation severity 1, 6

Imaging Strategy

First-Line Imaging

• Ultrasound is the preferred initial imaging study due to:
  • No radiation exposure (critical in pediatric population)
  • Wide availability
  • Superior visualization in children due to less body fat
  • Ability to evaluate multiple abdominal structures including spleen, pancreas, kidneys 1, 4

Conditional Advanced Imaging

• CT scan with IV contrast should be reserved for:
  • Equivocal or inconclusive ultrasound findings with persistent high clinical suspicion
  • Suspected trauma with hemodynamic instability
  • When surgical pathology cannot be excluded 1, 6, 4
• MRI may be considered as radiation-free alternative when CT would otherwise be indicated, though it requires more time and is more expensive 5

Critical Pitfall: Avoiding Overinvestigation

The most important evidence-based finding is that extensive diagnostic testing does not improve prognosis in chronic abdominal pain. A systematic review of 1,331 children followed for median 5 years demonstrated that 29.1% had persistent abdominal pain regardless of whether they underwent extensive testing or clinical diagnosis alone 2. This means:

• In the absence of alarming symptoms (weight loss, bloody stools, severe vomiting, fever, significant anemia), additional diagnostic testing beyond ultrasound does not influence outcomes 2
• The prognosis of clinically diagnosed chronic abdominal pain is identical to that diagnosed after extensive medical testing 2

Age-Specific Differential Considerations for LUQ Pain

Infants and Young Children (<5 years)

• Splenic trauma (even minor trauma can cause injury due to elastic rib cage transmitting force) 5
• Constipation (can cause diffuse or localized pain) 7
• Gastroenteritis 3

School-Age Children (5-12 years)

• Functional abdominal pain (most common in chronic cases) 2
• Splenic pathology (trauma, infection-related splenomegaly) 5
• Gastritis 3
• Renal pathology (left kidney stones, pyelonephritis) 7

Adolescents (>12 years)

• All of the above plus consideration of:
  • Splenic trauma from sports injuries 5
  • Pancreatitis 6
  • Functional disorders 2

Management Algorithm

1. History and physical examination focusing on alarm symptoms
2. Basic laboratory testing (CBC, urinalysis) 1
3. Ultrasound as first-line imaging 1, 4
4. If ultrasound inconclusive AND high clinical suspicion persists: Consider CT or MRI 1, 6
5. If no alarm symptoms and testing unrevealing: Avoid further extensive workup, as it does not change outcomes 2

Pain Management During Evaluation

• Pain control should not be withheld while awaiting diagnosis, as it does not mask symptoms or affect diagnostic accuracy 6
• For mild-moderate pain: Oral NSAIDs if no contraindications 6
• For severe pain: IV opioid analgesics titrated to effect 6

Special Consideration: Splenic Trauma

If trauma history exists (even seemingly minor), maintain high suspicion for splenic injury:

• Pediatric patients have unique anatomic features (thicker splenic capsule, more efficient arterial contraction) that make non-operative management highly successful (95-100% splenic preservation) 5
• Hemodynamic stability is defined as systolic BP >70 mmHg plus twice the child's age in years 5
• Even hemodynamically stable children with splenic injury require careful monitoring 5