Muscle Weakness Abnormal Gait or Difficulty Walking Elevated Creatine Kinase Respiratory Insufficiency Difficulty Swallowing Exercise Intolerance
Inflammatory Myopathy
14 to 25 per 100,000
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Pompe disease
2.5 per 100,000
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  • Inflammatory myopathies (IMs) are a heterogeneous group of immune-mediated disorders that can fall within several major categories including: polymyositis, dermatomyositis, overlap syndrome, cancer-associated myositis, and inclusion body myositis
  • Signs and symptoms of certain inflammatory myopathies may overlap with Pompe disease

Signs and Symptoms

  • Inflammatory myopathies may result in a weakness and loss of muscle strength, which is also common to patients with Pompe disease, and typically occurs in large muscles around the neck, shoulders, and hips
  • Similar to the experience of patients with Pompe disease, signs of muscle weakness in inflammatory myopathy can include difficulty getting up from a seated position, climbing stairs, or lifting objects above head level
  • Skin rashes on the eyelids which present as red or purple spots on the eyelids or red, scaly bumps on the knees, elbows or knuckles are observed in certain inflammatory myopathies such as dermatomyositis, but is not typically seen in Pompe disease


  • Genetic testing is currently available for many genetic disorders, including some inflammatory myopathies that have signs and symptoms that can overlap with Pompe disease
  • Similar to Pompe disease, tools such as laboratory tests (e.g. creatine kinase), electromyogram, and muscle biopsy may be obtained

The information presented is intended as a brief overview. It is not an exhaustive summary of inflammatory myopathy. For more information on inflammatory myopathy, visit:

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