lactase deficiency

Also found in: Dictionary, Thesaurus, Encyclopedia, Wikipedia.
Related to lactase deficiency: lactose intolerance, Lactase enzyme


β-d-galactosidase; an enzyme in the intestinal mucosa that hydrolyzes lactose, producing glucose and galactose.
lactase deficiency a deficiency of intestinal lactase, which causes abdominal distention and cramping and often diarrhea when milk is drunk. The condition is usually hereditary with an onset between infancy and early adulthood, and is more common in Blacks, American Indians, and East Asians (70 to 90 per cent) than in Whites (10 to 15 per cent). It may also occur secondary to massive small bowel resection or to diseases involving the mucosa, such as celiac disease, Crohn's disease, tropical sprue, and ulcerative colitis.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

lactose intolerance

A term that encompasses an array of adverse responses to consumption of non-human milk, in particular the inability to digest lactose, a sugar in milk and many dairy products. Up to 75% of adults have a decrease in lactase with age, which presents clinically as abdominal bloating, cramps, flatulence, diarrhea, nausea and/or vomiting, and borborygmi (a rumbling noise of the intestines).
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.
References in periodicals archive ?
In some black children, lactase deficiency may develop after the age of 3 years and is not associated with mucosal disease [29].
CONCLUSION: Despite the high prevalence of lactase deficiency in the Uzbek population, Uzbeks tolerate and regularly consume dairy products well.
"These results suggest that, despite patient manifestations, symptoms experienced at home were unlikely to be directly related to lactose-containing foods," especially among those patients without true lactase deficiency, the authors wrote.
Prospective comparison of indirect methods for detecting lactase deficiency. N Engl J Med 1975;293:1232-6.
Intestinal lactase deficiency and lactose intolerance in adults.
Response of patients with irritable bowel syndrome and lactase deficiency using unfermented acidophilus milk.
True congenital lactase deficiency is extremely rare (Altschuler & Liacouras, 1998; Wyllie & Hyams, 1999).
Small children born with lactase deficiency should not be fed any foods containing lactose.
Lactase deficiency is an example of food intolerance.
Examples of food intolerances include reactions- to monosodium glutamate (MSG), tyramine in cheese, caffeine in coffee, sulfites in wine, phenylethylamine in chocolate, or milk and its products in the case of someone who has a genetic lactase deficiency. Food hypersensitivity can be attributed to the ingestion of chemicals added to or sprayed on foods.
There are many medical problems that cause abdominal pain in children: peptic ulcers, Crohn's disease, lactase deficiency, and problems with the urinary system.
If lactase deficiency is suspected of causing your gas, your doctor probably will tell you to eliminate dairy foods from your diet so that your symptoms can be evaluated.