Felty syndrome is a disorder that includes rheumatoid arthritis, a swollen spleen, decreased white blood cell count, and repeated infections. It is rare.

Seropositive rheumatoid arthritis (RA); Felty's syndrome

The cause of Felty syndrome is unknown. It is more common in people who have had rheumatoid arthritis (RA) for a long time. People with this syndrome are at risk for infection because they have a low white blood cell count.

Symptoms include:

• General feeling of discomfort (malaise)
• Fatigue
• Weakness in leg or arm
• Loss of appetite
• Unintentional weight loss
• Ulcers in the skin
• Joint swelling, stiffness, pain, and deformity
• Recurrent infections
• Red eye with burning or discharge

In most cases, people who have this syndrome are not getting recommended treatment for RA. They may need other medicines to suppress their immune system and reduce the activity of their RA.

Methotrexate may improve the low neutrophil count. The drug rituximab has been successful in people who do not respond to methotrexate.

Granulocyte-colony stimulating factor (G-CSF) may raise the neutrophil count.

Some people benefit from removal of the spleen (splenectomy).

Without treatment, infections may continue to occur.

RA is likely to get worse.

Treating the RA, however, should improve Felty syndrome.

You may have infections that keep coming back.

Some people with Felty syndrome have increased numbers of large granular lymphocytes, also called LGL leukemia. This will be treated with methotrexate in many cases.

Contact your health care provider if you develop symptoms of this disorder.

Prompt treatment of RA with currently recommended medicines markedly decreases the risk of developing Felty syndrome.

Published Date: April 30, 2023
Published By: Neil J. Gonter, MD, Assistant Professor of Medicine, Columbia University, New York, NY, and private practice specializing in Rheumatology at Rheumatology Associates of North Jersey, Teaneck, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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