A condition in which there is an absence of lactase, an enzyme that breaks down lactose (milk sugar), in the cells of the small intestine.
Lactase deficiency results in a reduced ability to digest lactose, also known as lactose intolerance.
The condition may be permanent, or may occur temporarily after gastroenteritis, particularly in young children.
Symptoms include abdominal cramps, bloating, flatulence, and diarrhoea, all of which are caused by the laxative effect of the undigested sugar in the intestines.
Treatment is with a lactose-free diet.... lactase deficiency
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