Lactase deficiency is due to an insufficient level of lactase, which hydrolyzes lactose into glucose and galactose.

What is the Pathology of Lactase Deficiency?

The pathology of lactase deficiency is:

-Etiology: The cause of lactase deficiency is an inherited genetic fault that runs in families.

-Genes involved: LCT gene mutation.

-Pathogenesis: The sequence of events that lead to lactase deficiency are: A deficiency of intestinal lactase prevents hydrolysis of ingested lactose. The osmotic load of the unabsorbed lactose causes secretion of fluid and electrolytes until osmotic equilibrium is reached. Dilation of the intestine caused by the osmosis induces an acceleration of small intestinal transit, which increases the degree of maldigestion.

-Histology: The histology associated with lactase deficiency shows normal villi.

How does Lactase Deficiency Present?

Patients with lactase deficiency typically women present at age range of 25 to 30 years. The symptoms, features, and clinical findings associated with lactase deficiency include diarrhea.

How is Lactase Deficiency Diagnosed?

Lactase deficiency is diagnosed by hydrogen breath test, lactose tolerance blood test, and small bowel biopsy.

How is Lactase Deficiency Treated?

Lactase deficiency is treated by lactase tablets, and limiting milk and other dairy products. 

What is the Prognosis of Lactase Deficiency?

The prognosis of lactase deficiency is excellent. Most patients have a considerable improvement in signs and symptoms with dietary modification alone.