Severe transient pancytopenia associated with procainamide ingestion.

A 73-year-old woman was found to have clinically significant pancytopenia in association with procainamide hydrochloride ingestion. The syndrome, resembling systemic lupus erythematosus, which has been reported to develop in patients treated with this agent, is characterized by mild to moderate anemia and mild to moderate granulocytopenia. Severe granulocytopenia in patients taking procainamide and unrelated to a lupus syndrome has not previously been reported in association with significant thrombocytopenia. The clinical severity of this patient's presentation, suggesting an aleukemic leukemia, and its complete remission after cessation of procainamide administration occasional this report.