The Felty syndrome is a complication of rheumatoid arthritis characterized by the presence of three conditions: rheumatoid arthritis, an enlarged spleen (splenomegaly), and an abnormally low white blood cell count (neutropenia). The white blood cells that are low are called granulocytes (or neutrophils).
Felty syndrome predisposes to infections such as pneumonia or skin infections, because of the low white counts. There may also be ulcers in the skin over the legs. The cause of the syndrome is not known. White cells may be stored in excess in the spleen. especially in patients with Felty’s syndrome who have antibodies against granulocytes. In Felty syndrome, the underlying rheumatoid arthritis is managed in the standard manner. Patients with severe infectious disease may benefit from weekly injections of granulocyte colony stimulating factor (G-CSF) to stimulate the production of granulocytes.
The syndrome was named for the American physician Augustus Roi Felty (1895-1964) who first described it in 1924.