Creatine deficiency

An encyclopedia article about creatine deficiency

Creatine Deficiency
[[File:|250px|]]
Synonyms	N/A
Pronounce	N/A
Specialty	N/A
Symptoms	Developmental delay, intellectual disability, seizures
Complications	N/A
Onset	Infancy or early childhood
Duration	Lifelong
Types	N/A
Causes	Genetic mutations affecting creatine synthesis or transport
Risks	N/A
Diagnosis	Genetic testing, brain MRI, creatine levels in urine and blood
Differential diagnosis	N/A
Prevention	N/A
Treatment	Dietary supplementation, supportive therapies
Medication	N/A
Prognosis	Varies depending on type and treatment
Frequency	N/A
Deaths	N/A

Creatine deficiency is a group of rare genetic disorders that affect the body's ability to synthesize or transport creatine, a compound essential for energy storage and supply in muscle and brain tissues. Creatine deficiency syndromes are characterized by developmental delays, intellectual disabilities, and neurological symptoms such as seizures.

Types

There are three main types of creatine deficiency syndromes:

1. Guanidinoacetate methyltransferase (GAMT) deficiency: This is caused by mutations in the GAMT gene, leading to a deficiency in the enzyme responsible for the final step of creatine synthesis. Symptoms include developmental delay, intellectual disability, and seizures.

2. Arginine:glycine amidinotransferase (AGAT) deficiency: This is caused by mutations in the GATM gene, affecting the first step of creatine synthesis. It is the rarest form of creatine deficiency.

3. Creatine transporter deficiency: This is caused by mutations in the SLC6A8 gene, which affects the transport of creatine into cells. It is the most common form of creatine deficiency and primarily affects males due to its X-linked inheritance pattern.

Pathophysiology

Creatine plays a crucial role in the storage and transmission of energy in cells, particularly in muscle and brain tissues. It is synthesized in the liver and kidneys and then transported to other tissues. In creatine deficiency syndromes, the lack of creatine disrupts cellular energy metabolism, leading to the symptoms observed in affected individuals.

Symptoms

The symptoms of creatine deficiency can vary depending on the specific type but generally include:

- Developmental delay - Intellectual disability - Speech delay - Seizures - Behavioral problems - Hypotonia (reduced muscle tone)

Diagnosis

Diagnosis of creatine deficiency involves a combination of clinical evaluation, biochemical tests, and genetic testing. Key diagnostic tests include:

- Measurement of creatine and guanidinoacetate levels in urine and blood - Magnetic resonance spectroscopy (MRS) of the brain to assess creatine levels - Genetic testing to identify mutations in the GAMT, GATM, or SLC6A8 genes

Treatment

Treatment strategies for creatine deficiency vary depending on the type:

- GAMT deficiency: Supplementation with creatine monohydrate and dietary restriction of arginine and protein can help manage symptoms. - AGAT deficiency: Creatine supplementation is the primary treatment. - Creatine transporter deficiency: Creatine supplementation is less effective, but other supportive therapies, such as speech and occupational therapy, may be beneficial.

Prognosis

The prognosis for individuals with creatine deficiency varies. Early diagnosis and treatment can improve outcomes, particularly for GAMT and AGAT deficiencies. However, creatine transporter deficiency often has a more challenging prognosis due to limited treatment options.

Also see

• Creatine
• Metabolic disorder
• Genetic disorder
• Seizure disorder

Classification
External resources