Highlights & Basics
- Lactase deficiency exists in four distinct forms: primary (the most common), secondary, congenital, and developmental.
- Treatment of primary lactase deficiency is indicated only when it manifests as a clinical syndrome of lactose intolerance.
- Lactose intolerance is characterized by gastrointestinal symptoms such as diarrhea, bloating, and abdominal discomfort. Some patients have systemic symptoms (e.g., headache, poor short-term memory, severe tiredness, joint and/or muscle pain, atopic dermatitis, mouth ulceration)
- Dietary elimination and challenge are generally diagnostic.
- Treatment includes reduction or elimination of dietary lactose.
Quick Reference
History & Exam
Key Factors
Other Factors
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Definition
Epidemiology
Etiology
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Citations
Heyman MB; American Academy of Pediatrics, Committee on Nutrition. Lactose intolerance in infants, children, and adolescents. Pediatrics. 2006 Sep;118(3):1279-86.[Abstract][Full Text]
Suchy FJ, Brannon PM, Carpenter TO, et al. National Institutes of Health Consensus Development Conference: lactose intolerance and health. Ann Intern Med. 2010 Jun 15;152(12):792-6.[Abstract][Full Text]
Golden NH, Abrams SA, Committee on Nutrition. Optimizing bone health in children and adolescents. Pediatrics. 2014 Oct;134(4):e1229-43.[Abstract][Full Text]
- University of Virginia Digestive Health Center: lactose content of common dairy foods
- National Academies: dietary reference intakes for calcium and vitamin D
- National Institute of Diabetes and Digestive and Kidney Diseases: lactose intolerance
- US Department of Health and Human Services: dietary guidelines for Americans
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