short chain acyl-CoA dehydrogenase deficiency

What is Short Chain Acyl-CoA Dehydrogenase Deficiency?

Short-chain acyl-CoA dehydrogenase (SCAD) deficiency is an inherited disease in which the body cannot turn certain fats (known as short-chain fatty acids) into energy due to a deficient enzyme. Its symptoms can be triggered by illness or long periods without food.

Infants affected by the disease may display episodes of vomiting, low blood sugar, and fatigue. These episodes can be fatal. Affected infants may have difficulty feeding and fail to grow at the expected rate. Some show poor muscle tone, seizures, and small head size. If the disease is untreated, the child may show developmental delays and permanent learning difficulties.

Some people with SCAD deficiency do not display any symptoms until adulthood. In these cases, the main symptom is chronic muscle weakness. Some may experience periods of pain, nausea, and shortness of breath. It is thought that many cases are so mild that they are never diagnosed.

SCAD deficiency belongs to a group of diseases known as fatty acid oxidation disorders.

How common is Short Chain Acyl-CoA Dehydrogenase Deficiency?

SCAD deficiency affects 1 in every 40,000 to 100,000 newborns. Researchers have hypothesized that this disease may be more common because some people with the disease are asymptomatic or have mild symptoms.

How is Short Chain Acyl-CoA Dehydrogenase Deficiency treated?

It is critical that people with SCAD deficiency avoid going long periods of time without food. Infants and children with SCAD deficiency may require feedings at regular intervals throughout the night. A cornstarch paste is often recommended to provide a sustained release of energy between meals. Foods high in carbohydrates and low in fat are also recommended. During times of illness, dietary rules must be very carefully followed. If the child cannot eat food for any reason, intravenous glucose must be administered promptly.

Some physicians recommend carnitine supplements for people with SCAD deficiency.

What is the prognosis for a person with Short Chain Acyl-CoA Dehydrogenase Deficiency?

The prognosis for a person with SCAD deficiency varies widely and depends upon the severity of his or her symptoms. In some cases, infants with the disease can die early in life. The prognosis for those who live into adolescence and adulthood and/or develop symptoms of muscle weakness later in life is not known. Some people with the mutations that cause this disease do not develop symptoms, or have mild undiagnosed symptoms.