Diagnosing Cryopyrin-Associated Periodic Syndromes (CAPS)

CAPS—A Rare, Lifelong Disease^1-3

CAPS is a group of rare, genetic diseases that include Familial Cold Autoinflammatory Syndrome (FCAS) and Muckle-Wells Syndrome (MWS).^1-3

Prevalence of CAPS is estimated at 1 in 1 million. Approximately 300 patients are estimated to suffer from CAPS in the United States.²

• CAPS is caused by genetic mutations, often in the NLRP3 (or CIAS1) gene^2,3
• These mutations result in overproduction of the proinflammatory cytokine, interleukin-1 beta (IL-1β)¹
• Without treatment, debilitating and recurrent symptoms of CAPS can disable patients for hours or last for days^4-6
• CAPS can remain undiagnosed and untreated due to the rarity of the disease and the resemblance of symptoms to other conditions^2,7

Diagnosing CAPS

CAPS is a challenging differential diagnosis. While symptoms may resemble other illnesses, CAPS symptoms are chronic in nature.⁸

If a patient reports any of the following symptoms of CAPS on a daily or ongoing basis, or in response to changes in temperature or the environment, a diagnosis of Familial Cold Autoinflammatory Syndrome ( FCAS) or Muckle-Wells Syndrome (MWS) may be considered:

• Urticaria^4,5
• Fever or chills^4,5
• Headache or migraine⁵
• Fatigue or malaise^4,5
• Conjunctivitis^4,5
• Arthralgia^4,5
• Myalgia⁵
• Proper diagnosis of CAPS should include^2,5:
• Age of onset of symptoms, a full assessment of symptoms, family history, and a complete medical history from birth onward
• For some patients, confirmation may also be made through genetic testing

CAPS—A Familial Disease

• Genetic mutations in the NLRP3 (or CIAS1) gene are usually autosomal-dominant inherited mutations^2,3
• Knowledge of the family connections in CAPS can be valuable to the health of future generations:
• A link to an ancestor with CAPS may be revealed
• Another family member presently suffering from the disease may be diagnosed

Use the downloadable assessment below to help you when identifying and diagnosing CAPS patients in your practice.