Felty's Syndrome

Summary The clinical and hæmatological features of eight cases of Felty's syndrome are described, and are compared with those of other cases reported in the English literature. The three principal features are chronic rheumatoid arthritis, splenomegaly and neutropenia ; other less common features include hepatomegaly, pigmentation, lymph‐node enlargement and chronic leg ulceration. Infections are common, and are often recurrent and prolonged. The neutropenia is marked, counts of less than 1000 per cubic millimetre being the rule ; it is usually unaffected by infection. A mild anæmia is common, and occasionally an autoimmune acquired hæmolytic anæmia is associated. Symptomless thrombocytopenia may occur. The marrow is usually hyperplastic, but “maturation arrest” of the granulocytic series is not common. The administration of adrenocortical steroids in general causes either no increase in white cells, or a temporary increase which is not sustained despite continued treatment. It is concluded that the administration of steroids is not a satisfactory treatment for the neutropenia of Felty's syndrome. Splenectomy usually results in permanent increase in neutrophils. The importance of distinguishing between short‐term and long‐term response is stressed. In the great majority of cases there is an immediate increase in neutrophils to normal or above normal counts, the maximum count occurring within two to seven days. Subsequently the count falls; usually it remains within normal limits, but in some cases it falls to presplenectomy or lower‐than‐normal levels after weeks or months. Thus splenectomy cannot be said to be successful until the patient has been followed for at least many months.