Adenosine monophosphate deaminase deficiency type 1

Adenosine monophosphate deaminase deficiency type 1
Synonyms	Myoadenylate deaminase deficiency, AMP deaminase deficiency
Pronounce	N/A
Specialty	Neurology, Genetics
Symptoms	Exercise intolerance, muscle pain, cramps, fatigue
Complications	N/A
Onset	Adolescence or adulthood
Duration	Chronic
Types	N/A
Causes	Genetic mutation in the AMPD1 gene
Risks	Family history
Diagnosis	Muscle biopsy, genetic testing
Differential diagnosis	McArdle disease, mitochondrial myopathy
Prevention	N/A
Treatment	Exercise therapy, dietary modifications
Medication	N/A
Prognosis	Variable, generally benign
Frequency	Rare
Deaths	N/A

A genetic disorder affecting muscle metabolism

Adenosine monophosphate deaminase deficiency type 1 (AMPD1 deficiency) is a genetic disorder that affects the metabolism of muscle cells. It is characterized by a deficiency in the enzyme adenosine monophosphate deaminase (AMPD), which plays a crucial role in the purine nucleotide cycle.

Pathophysiology

AMPD1 deficiency is caused by mutations in the AMPD1 gene, which encodes the enzyme adenosine monophosphate deaminase. This enzyme is responsible for converting adenosine monophosphate (AMP) to inosine monophosphate (IMP) in the purine nucleotide cycle. The deficiency leads to an accumulation of AMP and a decrease in IMP, affecting the energy metabolism in muscle cells.

Clinical presentation

Individuals with AMPD1 deficiency may experience symptoms such as muscle weakness, fatigue, and exercise intolerance. These symptoms are often exacerbated by physical activity and can vary in severity among affected individuals. Some individuals may remain asymptomatic.

Diagnosis

Diagnosis of AMPD1 deficiency is typically made through a combination of clinical evaluation, muscle biopsy, and genetic testing. Muscle biopsy may show reduced AMPD activity, while genetic testing can identify mutations in the AMPD1 gene.

Management

There is currently no cure for AMPD1 deficiency. Management focuses on symptom relief and may include lifestyle modifications such as avoiding strenuous exercise. Some patients may benefit from nutritional supplements, although their efficacy is variable.

Genetics

AMPD1 deficiency is inherited in an autosomal recessive manner. This means that an individual must inherit two copies of the mutated gene, one from each parent, to be affected by the disorder. Carriers, who have only one copy of the mutated gene, typically do not show symptoms.

Related pages

• Metabolic myopathy
• Purine metabolism
• Genetic disorder
• Muscle weakness