Epidemiology
Etiology
Pathophysiology
Clinical features
Diagnostics
- Hydrogen breath test
- The amount of hydrogen in the expired air increases after administering lactose in the fasting state.
- Procedure
- Fasting for 8–12 hours
- Ingestion of lactose
- Measurement of breath hydrogen levels at baseline and at 30‑minute intervals over 3 hours
- Breath hydrogen levels > 20 ppm are considered diagnostic of lactose intolerance.
- Stool analysis
- ↑ Stool osmotic gap
- ↓ Stool pH (< 6): due to lactose fermentation by colonic bacterial flora
Treatment
- Avoid or reduce intake of milk products: lactose‑free or lactose‑reduced products
- Oral lactase supplements