lab 17 hydrogen breath Flashcards
what is lactose?
a disaccharide sugar found in milk and milk products
what is lactose made up of?
glucose and galactose
what is lactose malabsorption?
when there is a moderate deficiency of lactase; it is essentially symptom-free
what is lactose intolerance?
it is seen when the lactase enzyme is absent or so deficient that most of the lactose remains in the GI tract; it retains or osmotically draws water in, causing diarrhea and distention; it is also metabolized by bacteria in the rumen
what do the bacteria in the colon do to the lactose?
they fermented it to fatty acids and hydrogen gas
what happens to the hydrogen gas produced by the bacteira?
most of it is eliminated through flatus, some is reabsorbed into the blood stream and carried to the lungs and expired in the breath about one hour after ingestion of lactose
when do lactose malabsorption symptoms appear and why?
they appear at 3-5 years of age, when genetic makeup shuts off lactase production
what happens when 18-25 grams of lactose is given to adults who are deficient in lactase?
the hydrogen level in their alveolar air increases by at least 20ppm within 3 hours
can severity be evaluated from amount of hydrogen gas in the breath?
not necessarily but higher severity is usually associated with higher hydrogen gas levels (it is considered lactose intolerance when there are acute symptoms of discomfort following dietary exposure to milk or milk products
