Trehalase deficiency

Alternate names

Trehalose intolerance

Definition

Trehalase deficiency is a metabolic condition in which the body lacks an enzyme called trehalase and is not able to convert trehalose, a disaccharide (sugar composed of two monosaccharides) into glucose (sugar composed of one monosaccharide).

Summary

• Trehalose is found naturally in mushrooms, algae and insects. Trehalose may additionally be found in manufactured food products, medications, and cosmetics.
• For trehalose to be digested and absorbed by the digestive system, it must be broken down into glucose. Individuals with this deficiency are therefore unable to breakdown and absorb trehalose.
• This may lead to vomiting, abdominal discomfort and diarrhea after eating foods containing trehalose.

Epidemiology

Studies suggest that this condition is very rare in general; however it is more frequent in Greenland natives (where it has been reported in 8% of the population). Unfortunately for the rare diseases, there's often not a calculated incidence or prevalence. There is no official method for tracking these conditions. It is possible that the incidence is underreported given the similarity of symptoms to other more common digestive disorders such as irritable bowel syndrome. As the use of trehalose increases, we may see an increase in cases reported in the medical literature.

Cause

• Trehalase deficiency is caused by mutations in the TREH gene. The TREH gene codes for an enzyme that breaks down trehalose, a sugar made of two glucose molecules (disaccharide) into a digestible sugar or glucose, called a monosaccharide.
• When there is a mutation in the TREH gene, the enzyme has reduced or absent function, which results in undigested sugar entering into the bowel (digestive system). There, it goes through a process called fermentation, where sugars are converted to acids, gases, or alcohol. This leads to the production of gases, diarrhea, and other symptoms of abdominal pain and discomfort.

Inheritance

Both autosomal recessive and autosomal dominant inheritance patterns have been described in the medical literature.

Signs and symptoms

Individuals that have trehalase deficiency experience abdominal discomfort after consuming foods that contains trehalose, a type of sugar. The symptoms are typically similar to irritable bowel syndrome and might include: bloating, abdominal pain, diarrhea, vomiting, and gas.

Treatment

Treatment involves avoidance or restriction of products that contain trehalose.

NIH genetic and rare disease info

• NIH info on Trehalase deficiency

Trehalase deficiency is a rare disease.

This article is a stub. You can help WikiMD by registering to expand it. Editing is available only to registered and verified users. WikiMD is a comprehensive, free health & wellness encyclopedia.