General
Myopathy

Muscle Weakness Abnormal Gait or Difficulty Walking Elevated Creatine Kinase Respiratory Insufficiency Difficulty Swallowing Exercise Intolerance
Myopathy, General Mobile_LightDot Mobile_LightDot Mobile_LightDot Mobile_LightDot Mobile_LightDot
Pompe disease
2.5 per 100,000
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Overview

  • Myopathy is a broad term that refers to muscle weakness, generally in skeletal muscles, due to a dysfunction in the muscle fibers
  • Many signs and symptoms of myopathy overlap with Pompe disease

Signs and Symptoms

  • Certain myopathy symptoms may overlap with Pompe disease, including:
    • Generalized weakness
    • Muscle pain
    • Exercise intolerance
    • Fatigue
  • Similar to Pompe disease, most myopathies present with weakness affecting the proximal musculature
  • A distinctive walking pattern (e.g., waddling, walking on the balls of the feet, difficulty running, etc), that can also be present in patients with Pompe disease, may be evident, particularly in the early stages of the disease
  • Other symptoms which should raise clinical suspicion of myopathy can include: muscle atrophy, recurrent myoglobinuria, myotonia, fatigable weakness, and muscle weakness appearing in discrete patterns
  • As observed in Pompe disease, severity, age of onset, and clinical presentation of myopathy vary
  • This variability in features of myopathy is dependent on underlying cause, as myopathies are classified as acquired or are inherited like Pompe disease
  • Typically, an inherited myopathy is characterized by a long disease duration while a sudden presentation later in life is more indicative of an acquired myopathy
  • While some forms of myopathy may have minimal impact to the patient, other causes of the disorder may be progressive, severely disabling, or life-threatening, similar to Pompe

Diagnosis

  • As in Pompe disease, genetic testing is currently available for many disorders that may cause various types of myopathies
  • To distinguish between the varying types of myopathies, clinicians may use the same tools as those used in the diagnostic pathway of Pompe disease such as electromyography and laboratory testing (e.g., creatine kinase)

The information presented is intended as a brief overview. It is not an exhaustive summary of general myopathy. For more information on general myopathies, visit:
https://www.ninds.nih.gov/Disorders/All-Disorders/Myopathy-Information-Page

For more information on the diagnosis of Pompe disease, visit Diagnosis of Infantile-Onset Pompe Disease and Diagnosis of Late-Onset Pompe Disease