From the Research
Myoadenylate deaminase deficiency is a genetic muscle disorder characterized by the lack or reduced activity of the enzyme adenosine monophosphate deaminase (AMPD1) in skeletal muscles, typically manifesting as exercise intolerance with symptoms such as muscle pain, cramping, and early fatigue during physical activity. This condition is relatively common, affecting approximately 1-2% of the general population, and is inherited in an autosomal recessive pattern, meaning a person must inherit two defective copies of the gene to develop the condition 1. The enzyme normally helps convert adenosine monophosphate (AMP) to inosine monophosphate (IMP) during exercise, which is an important step in energy production within muscle cells. Many affected individuals remain asymptomatic, while others may have mild to moderate symptoms that appear after intense exercise.
Key Characteristics of Myoadenylate Deaminase Deficiency
- Inherited in an autosomal recessive pattern
- Affects approximately 1-2% of the general population
- Manifests as exercise intolerance with symptoms such as muscle pain, cramping, and early fatigue
- Enzyme deficiency leads to impaired energy production in muscle cells
- Most affected individuals can lead normal lives with appropriate activity modifications
Diagnosis and Management
Diagnosis of myoadenylate deaminase deficiency can be suspected in patients with exercise intolerance and idiopathic hyperCKemia, and confirmed through muscle biopsy and molecular analysis 1. Management focuses on symptom relief through moderate exercise, avoiding excessive exertion, and sometimes supplementation with ribose, which may help improve energy production in muscle cells 2. The most effective management strategy is to encourage patients to maintain physical activity while avoiding excessive exertion, and to consider supplementation with ribose to alleviate symptoms. Despite the enzyme deficiency, most affected individuals can lead normal lives with appropriate activity modifications.