Does elevated urinary 5-hydroxyindole acetic acid level predict acute appendicitis in children?

Area of Science:

• Pediatric surgery
• Gastroenterology
• Biochemical diagnostics

Background:

• Acute appendicitis is a common pediatric surgical emergency requiring prompt diagnosis.
• Enterochromaffin cells in the appendix produce serotonin, a metabolite of which, 5-hydroxyindoleacetic acid (5-HIAA), was investigated as a potential diagnostic marker.
• Early detection is crucial to prevent complications, particularly in young children.

Purpose of the Study:

• To evaluate the diagnostic utility of urinary 5-hydroxyindoleacetic acid (5-HIAA) concentrations in spot urine samples for acute appendicitis in children.
• To determine if 5-HIAA levels can serve as a reliable biomarker for pediatric appendicitis.

Main Methods:

• Collected spot urine samples from 93 children with surgically confirmed acute appendicitis and 102 healthy children as controls.
• Measured urinary 5-hydroxyindoleacetic acid (5-HIAA) levels using high-performance liquid chromatography.
• Analyzed 5-HIAA distribution and calculated diagnostic performance metrics (sensitivity, specificity, AUC).

Main Results:

• No statistically significant difference in 5-HIAA distribution was observed between children with appendicitis, those with other abdominal pain causes, and healthy controls.
• The area under the curve (AUC) for 5-HIAA was 0.55, indicating poor diagnostic performance.
• Sensitivity and specificity for diagnosing acute appendicitis using 5-HIAA were 60.4% and 48.9%, respectively.

Conclusions:

• Urinary 5-hydroxyindoleacetic acid (5-HIAA) concentration in spot samples is not a reliable diagnostic method for acute appendicitis in children.
• The low sensitivity and specificity, along with the non-significant difference in levels, preclude its use as a clinical biomarker.
• Further research may be needed to explore other potential biomarkers for pediatric appendicitis.