title: Quinidine-induced neutropenia: report of a case with drug-dependent inhibition of granulocyte colony generation.
abstract: We describe a case of quinidine-induced agranulocytosis in which in vitro marrow culture studies suggested immune inhibition of committed human granulocyte-macrophage progenitors (CFU-GM). Autologous, but not allogeneic, inhibition of CFU-GM was seen with 'acute' serum from the patient in the presence of quinidine but not other drugs. Cytotoxic antibodies to mature granulocytes were not found. These studies provide a novel mechanism for drug-induced neutropenia and suggest that a battery of in vitro assays of progenitor and of mature granulocyte cytotoxicity might identify offending agents in suspected drug-induced neutropenias.
mesh_terms: D000380:Agranulocytosis / Q000139:chemically induced*; D001856:Bone Marrow Examination; D002927:Cimetidine / Q000009:adverse effects; D003114:Colony-Forming Units Assay; D006098:Granulocytes / Q000166:cytology; D006412:Hematopoietic Stem Cells / Q000187:drug effects; D006801:Humans; D008264:Macrophages / Q000166:cytology; D008297:Male; D008875:Middle Aged; D009503:Neutropenia / Q000139:chemically induced*; D011802:Quinidine / Q000009:adverse effects*
chemical_list: D002927:Cimetidine; D011802:Quinidine