Isobutyryl-CoA dehydrogenase deficiency

Isobutyryl-CoA dehydrogenase (IBD) deficiency is a condition that disrupts the breakdown of certain proteins. Normally, proteins from food are broken down into amino acids. Amino acids can be further processed to provide energy for growth and development. People with IBD deficiency have problems breaking down the amino acid valine.

Most people with IBD deficiency are asymptomatic, which means that they do not have any signs or symptoms of the condition. If signs or symptoms do appear, they typically show early in life and only last for a short period of time. These signs and symptoms can include weak muscle tone (hypotonia), developmental delays, slow growth, a low number of red blood cells (anemia), and seizures. Because IBD deficiency is rare and often does not cause signs and symptoms, it is difficult to know if the health problems seen in affected individuals are caused by this condition or if those health problems are unrelated to the condition. It is also unclear whether IBD deficiency causes health problems later in life.

Newborn screening, which identifies abnormal levels of certain compounds in the blood, can detect IBD deficiency. People with IBD deficiency have high levels of a compound called carnitine (specifically a form called C4-acylcarnitine). Cells use carnitine, a natural substance that is acquired mostly through the diet, to process fats and produce energy.

Other names

ACAD8 deficiency; IBD deficiency; Isobutyryl-CoA dehydrogenase deficiency; Isobutyryl-coenzyme A dehydrogenase deficiency; Isobutyrylglycinuria

Inheritance pattern

Autosomal recessive

Related genes

ACAD8

Source: MedlinePlus Genetics, U.S. National Library of Medicine.