Adult-onset Still's disease

Adult-onset Still's disease is a systemic inflammatory disease. The classic presentation is the triad of persistent high spiking fever, joint pain and a distinctive salmon-colored rash. Serum ferritin, a protein that binds iron, is elevated. There are no characteristic antibodies in the blood. The symptoms are similar to other inflammatory diseases and to autoimmune diseases which do have characteristic antibodies, which must be ruled out with tests for those antibodies. Prognosis is usually favorable but pulmonary, cardiovascular, and kidney manifestations may occasionally cause severe life-threatening complications.^[1] It is treated first with steroids such as prednisone. Drugs that block the action of Interleukin-1, particularly IL-1β, are effective in treating it.

Pathophysiology

The cause of adult-onset Still's disease is not known, but it presumably involves IL-1, since drugs that block the action of IL-1β are effective treatments. Interleukin-18 is expressed at high levels.^[1][2]

Signs and symptoms

The disease typically presents with arthralgia, fever, a 'salmon-pink' rash, and lymphadenopathy. Rheumatoid factor (RF) and anti-nuclear antibody (ANA) are classically negative and serum ferritin is elevated. Patients experiencing a flare-up from Adult-onset Still's disease usually report extreme fatigue, swelling of the lymph glands, and less commonly fluid accumulation in the lungs and heart.

Diagnosis

The diagnosis is clinical, not based upon serology.^[3] At least seven sets of diagnostic criteria have been devised, however the Yamaguchi criteria have the highest sensitivity. Diagnosis requires at least five features, with at least two of these being major diagnostic criteria.^[4]

Treatment

One set of 21 adult-onset Still's disease patients were divided into four types, according to clinical course patterns. These included monocyclic systemic disease, polycyclic systemic disease, chronic articular monocyclic systemic disease, and chronic articular polycyclic systemic disease. Chronic articular disease and polyarticular disease were at higher risk to develop disabling arthritis.^[5]

Adult-onset Still's disease is treated with anti-inflammatory drugs. Steroids such as prednisone are used to treat severe symptoms of Still's. Other commonly used medications include hydroxychloroquine, penicillamine, azathioprine, methotrexate, etanercept, anakinra, cyclophosphamide, adalimumab, rituximab, and infliximab.

Newer drugs target interleukin-1 (IL-1), particularly IL-1β. A randomized, multicenter trial reported better outcomes in a group of 12 patients treated with anakinra than in a group of 10 patients taking other disease-modifying antirheumatic drugs. ^[6] Other anti-IL1β drugs are being developed, including canakinumab and rilonacept.^[7]

The condition "juvenile-onset Still's disease" is now usually grouped under juvenile rheumatoid arthritis. However, there is some evidence that the two conditions are closely related.^[8]

Epidemiology

Adult-onset Still's Disease is rare and has been described all over the world. Prevalence is estimated at 1.5 cases per 100,000-1,000,000 population. There is a bimodal age distribution with one peak incidence between ages 15–25 and a second peak between ages of 36–46 years.^[9]

History

Still's disease is named after English physician Sir George Frederic Still (1861–1941).^[10][11] It was characterized by EG Bywaters in 1971.^[12]

See also

• Juvenile idiopathic arthritis

References