Beta-ketothiolase deficiency is a rare, autosomal recessive metabolic disorder in which the body cannot properly process the amino acid isoleucine or the products of lipid breakdown.

The signs and symptoms of beta-ketothiolase deficiency include vomiting, dehydration, trouble breathing, extreme tiredness, and occasionally convulsions.

As a result, harmful compounds can build up and cause the blood to become too acidic (ketoacidosis), which impairs tissue function, especially in the central nervous system.

[citation needed] In beta-ketothiolase deficiency, alpha-methyl-beta-keto-butyrate, alpha-methyl-beta-OH-butyrate and tiglyl glycine (upstream metabolites of the affected enzyme) may accumulate and may be detected on urine organic acid analysis by GC-MS.

Avoidance of isoleucine overload might prevent neurological complications, but currently there is no evidence to support this[citation needed] This article incorporates public domain text from The U.S. National Library of Medicine