Felty syndrome is a rare disorder that involves rheumatoid arthritis, a swollen spleen, decreased white blood cell count, and repeated infections.
The cause of Felty syndrome is unknown. It is more common in people who have had rheumatoid arthritis for a long time. People with this syndrome are at risk of infection because they have a low white blood cell count.
Pinals RS. Felty's syndrome. In: Firestein GS, Budd RC, Harris Jr. ED, McInnes IB, Ruddy S, eds. Kelley's Textbook of Rheumatology. 8th ed. Philadelphia, Pa: WB Saunders; 2008: chap 68.