Disease at a Glance

Hereditary neuropathy with liability to pressure palsies (HNPP) is a disorder that affects peripheral nerves, causing the nerves to be highly sensitive to pressure. Symptoms usually begin during adolescence or early adulthood but may develop anytime from childhood to late adulthood. Symptoms vary in severity. While some people never realize they have the disorder, others experience prolonged disability. The most common problem sites involve nerves in the wrists, elbows, and knees; however, the fingers, shoulders, hands, feet, and scalp can also be affected. Symptoms associated with HNPP occur in episodes, due to pressure on any single peripheral nerve. Symptoms may include numbness, tingling, and/or loss of muscle function (palsy), pain in the limbs (especially the hands), carpal tunnel syndrome (impairing the ability to use the fingers, hands, and wrists), and foot drop (making it hard or impossible to walk, climb stairs, or drive). Some people experience fatigue, generalized weakness, muscle cramps, pain in the muscles or bones, or lower back pain. An episode of symptoms associated with HNPP can last from several minutes to days or even months. Most people completely recover after an episode, but repeated episodes can cause permanent muscle weakness or loss of sensation. HNPP is most often caused by the loss of one copy (a deletion) of the PMP22 gene, but it may also be cause by a genetic change within this gene. It is inherited in an autosomal dominant manner. The diagnosis is made based on the symptoms present, electrodiagnostic testing, and genetic testing. HNPP is thought to be underdiagnosed, and it may be misdiagnosed as another disorder such as Charcot-Marie Tooth disease.
Estimated Number of People with this Disease
In the U.S. there may be between

30,000 to 200,000

What Information Does GARD Have For This Disease?

Many rare diseases have limited information. Currently GARD is able to provide the following information for this disease:

*Data may be currently unavailable to GARD at this time.
When do symptoms of this disease begin?
The most common ages for symptoms of a disease to begin is called age of onset. Age of onset can vary for different diseases and may be used by a doctor to determine the diagnosis. For some diseases, symptoms may begin in a single age range or several age ranges. For other diseases, symptoms may begin any time during a person's life.
Before Birth
Birth-4 weeks
Infant Selected
1-23 months
Child Selected
2-11 years
Adolescent Selected
12-18 years
Adult Selected
19-65 years
Older Adult Selected
65+ years
The common ages for symptoms to begin in this disease are shown above by the colored icon(s).


These symptoms may be different from person to person. Some people may have more symptoms than others and symptoms can range from mild to severe. This list does not include every symptom.
This disease might cause these symptoms:

9 Symptoms

Tile View
List View
Tile View
List View


Genetic Disease

Hereditary neuropathy with liability to pressure palsies is a genetic disease, which means that it is caused by one or more genes not working correctly.

The following gene(s) are known to be associated with this disease: PMP22, PMP22



All individuals inherit two copies of most genes. The number of copies of a gene that need to have a disease-causing variant affects the way a disease is inherited. This disease is inherited in the following pattern(s):


Next Steps

Talking with the Medical Team

Good communication between the patient, family, and medical team can lead to an accurate diagnosis. In addition, health care decisions can be made together which improves the patient’s well-being and quality of life.

Describing Symptoms

Describe details about the symptoms. Because there may be many different causes for a single symptom, it is best not to make a conclusion about the diagnosis. The detailed descriptions help the medical provider determine the correct diagnosis.

To help describe a symptom:

  • Use a smartphone or a notebook to record each symptom before the appointment
  • Describe each symptom by answering the following questions:
    • When did the symptom start?
    • How often does it happen?
    • Does anything make it better or worse?
  • Tell the medical team whether any symptoms affect daily activities

Preparing for the First Visit

Working with a medical team to find a diagnosis can be a long process that will require more than one appointment. Make better health decisions by being prepared for the first visit with each member of the medical team.

    Make informed decisions about health care: 
    • Prepare a list of questions and concerns before the appointment
    • List the most important questions first, not all questions may be answered in the first visit
    • Ask questions about symptoms, possible diagnoses, tests, and treatment options
    For future appointments:
    • Discuss what was not addressed at the last visit
    • Discuss changes in the quality of life for the patient, family, and caregivers
    • Discuss health goals and other issues in the patient’s and family’s life that may affect the health care decisions
    Take notes during the appointments to help remember what was discussed.

    Last Updated: Nov. 8, 2021