Hi Diha,

Lactase is an enzyme that the tips of the villi produce. If the villi are damaged, they can not produce lactase. If there's no lactase, it can't break down lactose [sugar component in dairy]. This is the reason many celiacs can not do dairy. Many times after they have healed, they can tolerate some about of dairy.

Interesting about testing the lactase levels for CD. That's not something I have ever heard of.

http://www.medicinenet.com/lactose_i...ce/article.htm

How old is your DD? Blood tests can be unreliable in kids under 2 years old.