What is AOSD?

Adult-onset Still’s disease, referred to as AOSD, is a systemic autoinflammatory disease. A rare type of inflammatory arthritis, AOSD causes inflammation that results in joint inflammation, pain, high fevers and rashes. Autoinflammatory diseases like AOSD1 are characterized by an overactive immune system, which mistakenly becomes active when there is no invasion to fight, causing damage to the body’s own cells. There is no cure for AOSD, but remission (having little to no visible symptoms) is possible.2

1. Arthritis Foundation. Adult Still’s Disease. Available from:
2. http://www.arthritis.org/about-arthritis/types/adult-onset-stills-disease/ (accessed May 2020)


What are the symptoms of AOSD?

AOSD mainly develops in people between the ages of 16-35.1 AOSD often starts off with a sore throat but people may experience other symptoms including: 1,3,4

Signs and Symptoms of Adult-onset Still’s disease (AOSD)

Is AOSD a rare or common disease?

AOSD is very rare. Estimates in Japanese and European populations suggest there are only between 1 and 34 cases per million people.5 AOSD does not run in families but research has shown that people with certain types of genes may be more likely to develop it.5 Men and women are equally likely to develop AOSD.4

What causes AOSD?

The cause of AOSD is unknown.4 It was only recently classified as an autoinflammatory condition due to a better understanding of its underlying mechanisms – specifically the important role of a signalling protein called an interleukin2 - but it differs from other autoinflammatory conditions in that it is not believed to be inherited.5 Many researchers believe an abnormal or excessive response to an infection or toxic substance may trigger the disorder in people who also have a genetic predisposition.4,5

What happens over the course of AOSD?

The symptoms of AOSD, their severity and frequency varies from one person to the next. In some people, AOSD develops suddenly, disappears almost as quickly, and may not return for many years, if ever. In others, AOSD is a chronic condition that can cause long-term, severe and disabling complications.4

When AOSD isn’t recognized and controlled, the chronic inflammation can lead to the deterioration, and eventual destruction, of the affected joints.4 In some cases, excess fluid can build up around the lungs and lead to breathing problems.4 Another serious but very rare complication in people with AOSD is macrophage activation syndrome. The activation of macrophages – cells of the immune system which destroy cells – can overwhelm the whole body, leading to life-threatening systemic symptoms and internal organ failure.5,6

How is AOSD diagnosed?

As the signs and symptoms of AOSD can be very similar to those of other serious conditions, such as other autoinflammatory syndromes, lupus and lymphoma,4,5 diagnosing AOSD in the past has been difficult, especially with the disease so rare and its symptoms so varied. But advances in the last 20 years have improved correct diagnosis.

Diagnosis of AOSD is normally based on a review of a patient’s current symptoms, medical history and a physical examination by a rheumatologist, specializing in skeletal and systemic autoinflammatory diseases. Diagnosis may involve blood tests and x-rays, which reveal changes to the bones or joints, or enlargement to the spleen or liver.

1. Arthritis Foundation. Adult Still’s Disease. Available from: 
2. http://www.arthritis.org/about-arthritis/types/adult-onset-stills-disease/ (accessed May 2020)
3. Jamilloux Y, Gerfaud-Valentin M, Henry T et al. Treatment of adult-onset Still’s disease: a review. Ther & Clin Risk Manage 2015;11:33–43.
4. Cush JJ. Autoinflammatory syndromes. Dermatol Clin. 2013;31(3):471–480.
5. National Organization for Rare Disorders. Adult onset Still’s Disease.  Available from: http://rarediseases.org/rare-diseases/adult-onset-stills-disease/ (Accessed May 2020)
6. Gerfaud-Valentin M, Yvan Jamilloux Y, Iwaz J et al. Adult-onset Still’s Disease. Autoimmune Rev 2014;13;708–722.
7. Arthritis Foundation. Understanding Macrophage Activation Syndrome. Available from: https://www.arthritis.org/health-wellness/about-arthritis/related-conditions/other-diseases/understanding-macrophage-activation-syndrome/ (accessed May 2020). 


What if you are experiencing symptoms of AOSD?

If you are displaying any of the symptoms of AOSD, it is important you speak to your doctor as soon as possible and work with them to obtain an accurate diagnosis.

Click here for guidance on finding a specialist doctor and what you need to know to prepare for your first appointment with an AOSD expert.


How is AOSD diagnosed?

There is no one specific test to diagnose AOSD. Instead, diagnosis is reached through a process of elimination and exclusion, based on a review of a patient’s current symptoms, medical history and a physical examination by a rheumatologist that specializes in skeletal and systemic autoinflammatory diseases. Diagnosis may involve blood tests and x-rays, which reveal changes to the bones or joints, or enlargement to the spleen or liver.

Download our eBook I’m Rare or Living with Recurrent Fever eBook to learn from the experiences of others diagnosed with AOSD and what it means to live with a rare periodic fever syndrome like AOSD

What is life like after AOSD diagnosis?

Being diagnosed with a disease like AOSD can be life-changing, emotionally as well as physically, with the frustration and pain of adapting to a life with AOSD limiting relationships, hobbies, and work. However, great progress in research and medicine in recent years has meant patients’ quality of life has improved. For more information and advice, learn more about living with AOSD or read how other patients are living with similar diseases.

Click here to learn more from an expert specialist on autoinflammatory diseases as well as helpful guidance on life with a recurrent periodic fever syndrome.


How is AOSD treated?

There are several treatment options available to doctors to prescribe for AOSD.

  • NSAIDs (non-steroidal anti-inflammatory drugs) can reduce the pain and inflammation caused by AOSD
  • Corticosteroids can be used to treat inflammation long-term, but there can be side effects
  • Methotrexate is often prescribed alongside corticosteroids as it allows lower doses of corticosteroids to be used
  • Biologics may be prescribed1 to target and block inflammation-causing substances in the body

Some doctors will recommend taking more than one type of drug to keep the condition under control. In chronic cases, medication may need to be taken even after symptoms fade. This is in order to keep inflammation under control and prevent further damage to joints and other organs.2,4

Good communication with doctors and specialists will help provide a better understanding of the diagnosis and the treatment options available.


Download our eBook I’m Rare or Living with Recurrent Fever eBook to learn from the experiences of others undergoing treatment for AOSD and how rare conditions like this one can affect everyday life activities

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