In vitro inhibition of hematopoiesis in a patient with systemic sclerosis treated with D-penicillamine.

A 66-year-old Japanese woman with severe scleroderma developed anemia and thrombocytopenia due to D-penicillamine (D-Pen) treatment, although the leukopenia was not markedly severe. Cessation of D-Pen and the start of corticosteroid therapy were followed by recovery from bicytopenia. We examined the in vitro inhibition of the clonogenic capacity of bone marrow hematopoietic progenitor cells of this patient by D-Pen, and found strong inhibition in burst-forming unit-erythroid and colony-forming unit-megakaryocyte assays, but not in colony-forming unit-granulocyte/macrophage assays. These findings suggest that bicytopenia in this patient was caused by D-Pen and may be due to different sensitivities in the hematopoietic lineage.