What is the initial workup for a 9-year-old presenting with hematochezia (blood in stool)?

Initial Workup for a 9-Year-Old with Hematochezia

The initial workup for a 9-year-old with hematochezia should include a thorough stool evaluation for infection, complete blood count, inflammatory markers, and consideration of abdominal/pelvic imaging, with prompt gastroenterology consultation for possible endoscopic evaluation. 1, 2

Initial Assessment

History and Physical Examination Focus Points

• Characterize the bleeding:
  • Amount (small streaks vs. larger volume)
  • Color (bright red vs. darker blood)
  • Timing (with or separate from bowel movements)
  • Associated symptoms (pain, diarrhea, fever, weight loss)
• Assess for hemodynamic instability:
  • Calculate shock index (heart rate divided by systolic blood pressure)
  • A score >1 indicates an unstable patient requiring immediate management 2

Laboratory Tests

1. Complete blood count (CBC) - to assess for anemia and signs of inflammation 1, 2
2. Inflammatory markers:
   • C-reactive protein (CRP)
   • Erythrocyte sedimentation rate (ESR)
   • Procalcitonin in cases of suspected severe infection 1
3. Stool studies:
   • Stool culture and ova/parasite examination
   • Clostridioides difficile toxin assay
   • Fecal calprotectin and lactoferrin (markers of intestinal inflammation) 1, 2
   • Fecal occult blood test to confirm presence of blood

Diagnostic Imaging

For patients with significant bleeding or concerning symptoms:

• Abdominal/pelvic CT with contrast should be considered, especially if there are signs of severe bleeding or abdominal pain 1
• Abdominal ultrasound may be appropriate as a first-line, radiation-free imaging option in pediatric patients

Endoscopic Evaluation

Despite the lower GI bleeding presentation, the American College of Gastroenterology recommends:

1. Upper GI endoscopy as the initial diagnostic procedure, even in cases of suspected lower GI bleeding, as 10-15% of severe hematochezia cases have upper GI sources 2

2. Colonoscopy after adequate bowel preparation if the patient is stable, which provides both diagnostic and therapeutic capabilities 2, 3

3. Combined upper and lower endoscopy is particularly valuable in pediatric IBD diagnosis, as EGD findings can be crucial for distinguishing between Crohn's disease and ulcerative colitis 3

Differential Diagnosis to Consider

Common causes of hematochezia in children include:

• Anal fissures (most common in young children)
• Infectious colitis
• Inflammatory bowel disease (IBD)
• Juvenile polyps
• Meckel's diverticulum
• Intussusception (typically in younger children)
• Hemorrhoids (less common in children)
• Vascular malformations 1, 4

Risk Stratification

The severity of bleeding should guide management decisions:

• Minor bleeding (hemodynamically stable, no significant anemia):

  • May be managed in outpatient setting with close follow-up

• Major bleeding (hemodynamic instability, significant anemia):

  • Requires immediate hospitalization
  • Consider blood transfusion if hemoglobin <70 g/L (higher threshold of 80 g/L for patients with cardiovascular disease) 2

Important Considerations

1. Age-specific concerns: In pediatric patients, inflammatory bowel disease is an important consideration, especially with chronic or recurrent bleeding 5, 3

2. Diagnostic yield: The combination of symptoms, blood markers, and stool markers (particularly calprotectin) has shown excellent diagnostic accuracy for IBD in pediatric patients with chronic diarrhea 5

3. Pitfalls to avoid:

   • Don't assume all rectal bleeding in children is from benign causes
   • Don't delay endoscopic evaluation in cases of significant or persistent bleeding
   • Don't forget to assess for hemodynamic instability, which would require immediate intervention

By following this structured approach to the evaluation of hematochezia in a 9-year-old, clinicians can efficiently identify the cause of bleeding and initiate appropriate management to reduce morbidity and mortality.