Felty's syndrome without rheumatoid arthritis?

Felty's syndrome (FS) is characterized by neutropenia and splenomegaly in patients with seropositive (RF+, anti-CCP+) rheumatoid arthritis (RA). As a result of neutropenia, affected persons are increasingly susceptible to infections. In the majority of patients, FS appears in the course of long-standing and well-established RA. Manifestations of FS without clinical but only with laboratory features of RA are extremely rare. We present a case of severe neutropenia and mild splenomegaly in a patient with high titers of RF and anti-CCP. For 4 years, patient's neutropenia remained asymptomatic. The neutropenia reduction to agranulocytosis was followed by successful methotrexate–corticosteroid therapy. Efficacy of the standard anti-RA therapy confirmed autoimmune mechanism of the Felty's neutropenia. The most important lesion from our case is to recognize this condition in the range of autoimmune rheumatic diseases without delay. We reviewed literature with non-articular FS.