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:
A physical exam will show:
A complete blood count (CBC) with differential will show a low number of white blood cells called neutrophils. Nearly all people with Felty syndrome have a positive test for rheumatoid factor.
An abdominal ultrasound may confirm a swollen spleen.
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.
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Review Date:
4/30/2023 Reviewed 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. |