Still's Disease (Adult-Onset Still's Disease)
What is Still's Disease (Adult-Onset Still's Disease)?
Adult-onset Still's disease is a rare inflammatory condition that affects the whole body. It causes high fevers, joint pain, and a distinctive salmon-colored rash. This condition is named after Dr. George Still, who first described it in children in 1896. When it appears in adults, doctors call it adult-onset Still's disease.
The disease belongs to a group of conditions called autoinflammatory disorders. Your immune system becomes overactive and attacks healthy tissues without a clear trigger. This leads to widespread inflammation throughout your body. Episodes can come and go, or the condition may become chronic and require ongoing management.
Still's disease is quite rare, affecting only about 1 in every 100,000 people. It typically appears in adults between ages 16 and 35, though it can develop at any age. Women and men are affected equally. Early diagnosis matters because proper treatment can prevent joint damage and other serious complications.
Symptoms
- High spiking fevers, often reaching 102°F or higher, typically once or twice daily
- Salmon-pink rash that appears and disappears, usually during fever episodes
- Severe joint pain and swelling, especially in the knees, wrists, and ankles
- Sore throat that doesn't respond to antibiotics
- Enlarged lymph nodes in the neck, armpits, or groin
- Muscle pain and weakness throughout the body
- Enlarged spleen or liver, causing abdominal discomfort
- Extreme fatigue that interferes with daily activities
- Weight loss without trying
- Chest pain when breathing deeply, due to inflammation around the heart or lungs
Some people experience only mild symptoms at first. The fever pattern is often the most distinctive feature, with temperatures spiking predictably each day and then returning to normal. The rash may be hard to spot and often appears only when fever is present.
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Causes and risk factors
The exact cause of adult-onset Still's disease remains unknown. Researchers believe it results from a combination of genetic factors and environmental triggers. Some studies suggest that viral or bacterial infections may trigger the condition in people who are genetically predisposed. However, no specific infection has been definitively linked to the disease. Your immune system essentially misfires, creating inflammation even when there's no infection to fight.
Risk factors for developing Still's disease are not well understood due to its rarity. The condition appears most commonly in young adults between 16 and 35 years old. Unlike many autoimmune conditions, gender does not seem to play a significant role. There is no clear family pattern, so having a relative with the condition does not substantially raise your risk. Smoking, diet, and other lifestyle factors have not been shown to cause Still's disease.
How it's diagnosed
Diagnosing adult-onset Still's disease can be challenging because there is no single definitive test. Doctors use a process of elimination, ruling out infections, cancers, and other inflammatory conditions that cause similar symptoms. Blood tests play a vital role in this process. Extremely high ferritin levels, often exceeding 1,000 ng/mL and sometimes reaching 5,000 ng/mL or higher, strongly suggest Still's disease. A glycosylated ferritin test showing less than 20% glycosylated ferritin further supports the diagnosis.
Rite Aid offers ferritin testing as part of our core blood panel. Getting your ferritin levels checked can help identify this rare condition early. Your doctor will also check for other markers of inflammation, such as elevated white blood cell counts and inflammatory proteins. Imaging tests may be ordered to look for joint inflammation or organ involvement. Because symptoms can mimic many other conditions, accurate blood testing is essential for proper diagnosis.
Treatment options
- Nonsteroidal anti-inflammatory drugs to reduce fever and joint pain during mild episodes
- Corticosteroids like prednisone to quickly control severe inflammation and symptoms
- Disease-modifying antirheumatic drugs such as methotrexate to prevent joint damage
- Biologic medications including anakinra, tocilizumab, or canakinumab for resistant cases
- Regular rest periods to manage fatigue and give your body time to recover
- Anti-inflammatory diet rich in fruits, vegetables, omega-3 fatty acids, and whole grains
- Physical therapy to maintain joint flexibility and muscle strength
- Stress management techniques like meditation or gentle yoga to reduce inflammation triggers
- Regular monitoring with blood tests to track disease activity and medication effects
- Close follow-up with a rheumatologist who specializes in inflammatory conditions
Concerned about Still's Disease (Adult-Onset Still's Disease)? Get tested at Rite Aid.
- Simple blood draw at your nearest lab
- Results in days, not weeks
- Share results with your doctor
Frequently asked questions
Still's disease in children is called systemic juvenile idiopathic arthritis, while the adult form is called adult-onset Still's disease. Both cause similar symptoms including high fevers, rash, and joint inflammation. However, adults are more likely to develop chronic arthritis that persists after initial treatment. Children often outgrow the condition, while adults may need long-term management.
Ferritin levels in adult-onset Still's disease are typically very high, often exceeding 1,000 ng/mL. Many patients have levels between 3,000 and 5,000 ng/mL or even higher during active disease. A glycosylated ferritin fraction below 20% is particularly suggestive of Still's disease. Ferritin levels usually decrease with successful treatment and rise again if the disease flares.
No, adult-onset Still's disease is not contagious. You cannot catch it from someone else or spread it to others. While infections may trigger the condition in some people, the disease itself is an inflammatory disorder caused by your own immune system. It is safe to be around others when you have Still's disease.
Some people experience a single episode that resolves with treatment and never returns. However, many patients develop a chronic or relapsing pattern that requires ongoing management. About one-third of patients have a single episode, one-third have intermittent flares, and one-third develop persistent chronic disease. Early treatment can improve outcomes and reduce the risk of permanent joint damage.
Flare triggers vary from person to person and are not fully understood. Some patients notice flares after infections, stress, or physical exhaustion. Others find no clear pattern to their flares. Keeping a symptom diary can help you identify personal triggers. Working with your rheumatologist to adjust medications before or during potential trigger periods may help prevent severe flares.
Diagnosis often takes weeks to months because doctors must rule out many other conditions first. The average time from symptom onset to diagnosis is several months. Blood tests showing very high ferritin levels can speed up diagnosis when combined with typical symptoms. Seeing a rheumatologist early in the process usually shortens the time to diagnosis.
Not everyone needs lifelong medication for Still's disease. Some patients can stop treatment after their symptoms resolve and remain in remission. Others require ongoing medication to prevent flares and joint damage. Your treatment duration depends on your disease pattern, response to therapy, and risk of complications. Regular monitoring helps your doctor determine when it might be safe to reduce or stop medications.
While diet alone cannot treat Still's disease, an anti-inflammatory eating pattern may help reduce symptoms. Focus on foods rich in omega-3 fatty acids, colorful fruits and vegetables, and whole grains. Avoid processed foods, excess sugar, and refined carbohydrates that can promote inflammation. Some patients find that certain foods trigger their symptoms, so paying attention to your body's responses is helpful.
The most common long-term complication is chronic arthritis that causes joint damage and reduced mobility. Other potential complications include heart inflammation, lung problems, liver abnormalities, and an increased risk of a serious condition called macrophage activation syndrome. Regular blood tests and monitoring help catch complications early. Proper treatment significantly reduces the risk of serious complications.
Yes, regular ferritin testing is important for monitoring disease activity in Still's disease. Rising ferritin levels often signal an approaching flare or increased inflammation. Declining levels suggest your treatment is working. Most rheumatologists check ferritin every few months during active disease and less frequently once you're stable. Rite Aid offers convenient ferritin testing to help you track this important marker.