Adult-onset Still's disease
Adult-onset Still's disease (AOSD) is a form of Still's disease, a rare systemic autoinflammatory disease characterized by the classic triad of persistent high spiking fevers, joint pain, and a distinctive salmon-colored bumpy rash. The disease is considered a diagnosis of exclusion. Levels of the iron-binding protein ferritin may be extremely elevated with this disorder. AOSD may present in a similar manner to other inflammatory diseases and to autoimmune diseases, which must be ruled out before making the diagnosis.
Signs and symptoms
The disease typically presents with joint pain, high fevers, a salmon-pink macular or maculopapular rash, enlargement of the liver and spleen, swollen lymph nodes, and a neutrophil-predominant increased white blood cell count in the blood.
The cause of adult-onset Still's disease is unknown, but it presumably involves interleukin-1 (IL-1), since medications that block the action of IL-1β are effective treatments. Interleukin-18 is expressed at high levels.
The diagnosis is clinical, not based upon serology.
|Major criteria||Minor criteria|
|Fever of at least 39 °C for at least one week||Sore throat|
|Arthralgias or arthritis for at least two weeks||Lymphadenopathy|
|Nonpruritic salmon-colored rash (usually over trunk or extremities while febrile)||Hepatomegaly or splenomegaly|
|Leukocytosis (10,000/microL or greater), with granulocyte predominance||Abnormal liver function tests|
|Negative tests for antinuclear antibody and rheumatoid factor|
People with AOSD generally experience one of two patterns in the disease:
- a debilitating pattern of fevers, pain, and other systemic symptoms, or
- a somewhat less aggressive pattern, in which the main symptom is arthritis and chronic joint pain.
Adult-onset Still's disease is treated with anti-inflammatory medications. Steroids such as prednisone are used to treat severe symptoms of Still's. Other commonly used medications include hydroxychloroquine, penicillamine, azathioprine, methotrexate, etanercept, anakinra, tocilizumab cyclophosphamide, adalimumab, rituximab, and infliximab.
Newer medications 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.
Adult-onset Still's Disease is rare and has been described all over the world. The number of new cases per year is estimated to be 1.6 per 1,000,000 population.
Prognosis is usually favorable but manifestations of the disease affecting the lungs, heart, or kidneys may occasionally cause severe life-threatening complications.