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Get a Handle on the Cold Truth About CAPS

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Find out if your symptoms indicate CAPS.

Do you or someone you care for experience constant rashes, fevers, aching joints, or other unexplained symptoms? Has it been happening for as long as you can remember? It could be symptoms of rare and painful genetic conditions called Cryopyrin-Associated Periodic Syndromes (CAPS).

These symptoms often occur after exposure to cold or damp air, or a drop in temperature. However, CAPS symptoms may also show up for no clear reason.

CAPS and its subtypes—FCAS (Familial Cold Autoinflammatory Syndrome), MWS (Muckle-Wells Syndrome), and NOMID (Neonatal-Onset Multisystem Inflammatory Disease)—are such rare genetic disorders that they're often misdiagnosed.

Because the gene that causes CAPS can be passed down through the generations, it's important to learn as much as you can about these rare hereditary conditions.

About CAPS symptoms

It can be difficult to recognize CAPS and its associated genetic diseases. The symptoms can often be mistaken for more common conditions. However, here are a few CAPS facts that can be clues to you or your doctor:

  • People with CAPS often get a rash or hives, but the rash that comes with CAPS is usually not itchy
  • The symptoms of CAPS are usually not very noticeable in the morning but get worse over the course of the day
  • The symptoms of CAPS usually start in infancy or childhood. They rarely begin in adulthood
  • Even in the mildest form of CAPS, symptoms can be painful

The group of rare genetic diseases that form CAPS are caused by a genetic abnormality that can be passed down from parents to children. The abnormality may also show up randomly in people with no family history of hereditary diseases. Family members who have CAPS may share a variety of symptoms, such as rash, fever, joint pain, eye swelling or redness, and hearing loss.

People may not know that they have CAPS, but they certainly know something is wrong because of the uncomfortable symptoms. Symptoms can also occur without an obvious reason. People may experience a flare (when the symptoms of the genetic disease are more pronounced) after they are exposed to cold temperatures.

This group of genetic diseases affects only about 1 in 1 million people. However, many patients may still not be diagnosed. Doctors may not think of CAPS at first. Many people with undiagnosed CAPS find that this lifelong disease can be very frustrating. People who are severely affected may develop permanent damage to the major organs and joints in their bodies.

Only a doctor can determine whether a person has CAPS. That's why people who think they or someone they know may have CAPS should talk to their doctor about their symptoms and treatment options.

CAPS symptoms are often managed by special doctors, such as rheumatologists and allergists. Rheumatologists treat pain and swelling in joints and muscles. Allergists take care of patients with certain types of rashes or sensitivities.