Final answer:
Lactose intolerance is diagnosed using the hydrogen breath test, intestinal biopsy, and stool acidity test, with the hydrogen breath test being the most common. Lactase deficiency is the underlying issue, and symptoms can be managed with lactose-free products and supplements.
Step-by-step explanation:
Diagnosing Lactose Intolerance
There are several methods to diagnose lactose intolerance. The most common is the hydrogen breath test, where after fasting, a patient ingests lactose and their breath is analyzed for hydrogen, which indicates bacterial metabolism of lactose in the gut. Another method is the intestinal biopsy, which can confirm lactose intolerance by measuring lactase enzymes or mRNA in the biopsy tissue, although this is less common due to its complexity. For small infants, stool acidity is tested, as other testing methods may be risky or impractical. Lactose intolerance is a result of lactase deficiency, which prevents the digestion of lactose and leads to symptoms like diarrhea and vomiting upon consumption of dairy products. Lactose-free dairy products and dietary supplements are available to help those with lactose intolerance manage their symptoms.