L-arginine:glycine amidinotransferase (AGAT) deficiency

Synonyms

1

Overview

L-arginine:glycine amidinotransferase (AGAT) deficiency is a rare condition that primarily affects the brain. People with AGAT deficiency generally have mild to moderate intellectual disability and delayed speech development. Some affected individuals develop autistic behaviors that affect communication and social interaction. Children with arginine:glycine amidinotransferase deficiency may not gain weight and grow at the expected rate (failure to thrive), and have delayed development of motor skills such as sitting and walking. Affected individuals may also have weak muscle tone and tend to tire easily.

Symptoms

• Seizures when they have fever
• Delayed language development
• Muscle weakness
• Failure to thrive
• Autistic behaviors
• Delayed motor milestones (i.e. walking, sitting)

Causes

AGAT deficiency is caused by changes (mutations) in the GATMgene and is inherited in an autosomal recessive manner.

Diagnosis

Extra- and intracellular creatine pool, Creatine in brain, Creatine in muscle, Creatine in body fluids

Treatment

Treatment of AGAT deficiency is focused on increasing cerebral creatine levels and generally consists of supplementation with creatine monohydrate.