Severe prolonged red blood cell aplasia and thrombocytopenia induced by parvovirus B19 infection in a patient with sarcoidosis.

We describe an acromegalic patient who developed a parvovirus B19 (PVB19) infection concomitantly with sarcoidosis, which was complicated by chronic red blood cell aplasia and severe thrombocytopenia, despite disappearance of the virus from serum and the production of high levels of specific polyclonal antibodies to PVB19. Mitogen stimulation of the patient's peripheral blood mononuclear cells induced oversecretion of interferon-gamma (IFN-gamma). Because hematopoietic suppression by IFN-gamma has been reported, a possible mechanism underlying reticulocytopenia and thrombocytopenia could involve IFN-gamma.