Blau Syndrome: Causes, Symptoms, and Treatment
Medically reviewed by Achuta Uppu, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Blau Syndrome?
Blau syndrome is usually treated by a pediatric rheumatologist, a doctor who treats joint and immune problems in children, along with an eye doctor called an ophthalmologist. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is Blau syndrome?
Blau syndrome is a very rare inflammatory disorder. That means it causes swelling in body tissues. It mainly affects the skin, joints, and eyes. Signs usually start before age 4. Fewer than 1 in 1 million children worldwide have it.
The cause is a change in a gene called NOD2. This gene helps the immune system fight germs. The changed gene makes the immune system overactive. It causes swelling even when no infection is present.
Symptoms
Symptoms usually appear in early childhood and can include:
- A lasting rash with small, hard lumps under the skin. This is usually the first sign. It shows up on the torso, arms, and legs.
- Swollen, painful joints. The swelling comes from the joint lining. Doctors call this synovitis. It often starts in the hands, feet, wrists, and ankles.
- Eye inflammation called uveitis, which can cause eye pain, redness, blurred vision, and sensitivity to bright light.
Over time, joint swelling can limit movement. Eye inflammation can harm vision, or even cause blindness, if not treated. Some people also have kidney problems or inflamed blood vessels.
Causes and who gets it
Blau syndrome is passed down in an autosomal dominant pattern. That means a change in one copy of the NOD2 gene is enough to cause it. Most children get the changed gene from a parent who has the condition. Sometimes there is no family history. The gene change happened for the first time in that child.
How doctors diagnose it
Doctors look at the rash, joints, and eyes. They ask about family history. Blood tests can show signs of inflammation. A biopsy removes a tiny piece of skin or joint tissue. A lab looks at it under a microscope. The tissue may show clumps of immune cells called granulomas. A genetic test can find the NOD2 change and confirm the diagnosis.
Treatment
There is no cure, so treatment aims to control swelling and protect the joints and eyes. Doctors often start with NSAIDs. These are anti-inflammatory medicines such as ibuprofen. They may add corticosteroids, which calm the immune system. If those do not work well, other medicines can help. These include methotrexate, cyclosporine, anti-TNF drugs, and canakinumab, an anti-IL1 medicine. Regular eye exams matter because uveitis can harm vision without clear symptoms.
When to see a doctor
See a doctor if a child has a lasting rash plus swollen, painful joints. Tell the doctor about any eye redness, pain, or light sensitivity. Get care right away for sudden eye pain or a sudden drop in vision. Untreated eye inflammation can cause permanent vision loss.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. Either can refer a child to specialists like pediatric rheumatology. They can also help manage the long-term treatment.
Common questions
Can Blau syndrome be prevented?
No. It is an inherited genetic condition, so it cannot be prevented. Genetic counseling can help families understand the chance of passing the gene to a child.
Can Blau syndrome be cured?
There is no cure. Treatment aims to control swelling, ease pain, and protect the joints and eyes. With regular care, many children keep good vision and movement.
Why are regular eye exams so important?
Uveitis can harm vision before a child notices any problem. Regular eye exams help catch it early. Early treatment can prevent lasting damage.
What medicines are used?
Doctors often start with NSAIDs and corticosteroids. If those are not enough, other medicines can help. These include methotrexate, cyclosporine, anti-TNF drugs, and canakinumab. The choice depends on the body parts affected and how bad the disease is.
Sources
- MedlinePlus Genetics - Blau syndrome
- National Organization for Rare Disorders - Blau syndrome
- PMC, NIH - Diagnostics challenges and therapeutic response in Blau syndrome
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
