Systemic plasmacytosis. A syndrome of peculiar multiple skin eruptions, generalized lymphadenopathy, and polyclonal hypergammaglobulinemia.

A description is given of two patients with peculiar multiple skin eruptions, asymptomatic generalized lymphadenopathy, and polyclonal hypergammaglobulinemia. Both patients were admitted to our hospital for further evaluation of an increased erythrocyte sedimentation rate and hypergammaglobulinemia discovered during routine medical examinations. Despite various investigations, the underlying disease causing the hypergammaglobulinemia was not found. Histologic examination disclosed dense perivascular infiltration of plasma cells in the dermis. In the lymph nodes, considerable plasma cell infiltration was found from the cortex to the medulla. These plasma cells were mature and showed no cellular atypism. The association of peculiar multiple skin eruptions, lymphadenopathy, and polyclonal hypergammaglobulinemia, which we have called "systemic plasmacytosis," signifies a new syndrome that can be differentiated from diseases reported previously.