Felty's syndrome associated with high levels of IgA rheumatoid factor

A 64-year-old woman with rheumatoid arthritis developed Felty's syndrome. Her serum contained large amounts of IgA rheumatoid factor (RF) but insignificant levels of IgM-RF and IgG-RF. It is postulated that the high levels of IgA-RF may have contributed to the neutropenia.