Lactose malabsorption and intolerance: pathogenesis, diagnosis and treatment

Area of Science:

• Gastroenterology
• Human Genetics
• Nutritional Science

Background:

• Lactose malabsorption results from decreased lactase enzyme activity in the small intestine.
• This leads to lactose intolerance, manifesting as gastrointestinal symptoms after dairy consumption.
• The genetic underpinnings of lactose malabsorption are well-established.

Purpose of the Study:

• To review the genetic basis, diagnostic methods, and treatment strategies for lactose malabsorption and intolerance.
• To highlight the distinction between lactose malabsorption and lactose intolerance.
• To emphasize the need for updated diagnostic protocols and clinical studies for lactose intolerance.

Main Methods:

• Review of existing literature on lactose malabsorption and intolerance.
• Discussion of diagnostic tests including genetic, endoscopic, and hydrogen breath tests.
• Analysis of factors influencing symptom development, such as lactose dose and gut microbiota.

Main Results:

• Lactose malabsorption has a known genetic basis and several diagnostic tests.
• Lactose intolerance is defined by symptom development post-lactose challenge versus placebo.
• Factors like lactose dose, lactase levels, gut flora, and GI sensitivity impact symptom risk.

Conclusions:

• Clearer diagnostic criteria and placebo-controlled testing are needed for lactose intolerance.
• Treatment options include dietary modifications and enzyme replacement.
• Further research is required to validate treatment strategies and clinical utility.