Cigarette smoking and chronic polyclonal B-cell lymphocytosis.

A syndrome associating a polyclonal increase of B-cells with binucleate lymphocytes in peripheral blood and a polyclonal increase of serum IgM, accompanied or not by splenomegaly and lymphadenopathy, has been reported in young to middle-aged women who are cigarette smokers. The majority of patients were HLA-DR7 positive and their clinical course remained stable over periods of years. We report four cases of this syndrome. In all patients, DNA analysis provided additional evidence that the lymphocytosis was polyclonal, while in one patient who met all other symptomatic criteria the total lymphocyte count was normal. This would suggest that unless careful attention is paid to the morphology of the lymphocytes, the syndrome may go undiagnosed.