title: Discrepancy between impedance and immunofluorescence platelet counting has implications for clinical decision making in patients with idiopathic thrombocytopenia purpura.
abstract: This study investigated whether differences occur between the impedance and immunofluorescence methods for platelet quantification in idiopathic thrombocytopenia purpura (ITP). Immunofluorescence gave a platelet count >50% higher than the impedance test in 9/35 (26%) patients, of which 4/35 (11%) were >100% higher. The clinical severity of thrombocytopenia was changed as a result of the immunofluorescence test in 14/35 (40%) patients. Neither mean platelet volume nor platelet distribution width predicted impedance/immunofluorescence method discrepancy. It is suggested that immunofluorescence platelet counts should be performed on all ITP patients when the implementation of a therapeutic or diagnostic intervention is being considered.
authors.affiliation: Department of Haematology, Addenbrooke's NHS Trust, Cambridge, UK.
authors.forename: Kristian M
authors.initials: KM
authors.lastname: Bowles
authors.forename: David M
authors.initials: DM
authors.lastname: Bloxham
authors.forename: David J
authors.initials: DJ
authors.lastname: Perry
authors.forename: Trevor P
authors.initials: TP
authors.lastname: Baglin
mesh_terms: D001777:Blood Coagulation; D005455:Fluorescent Antibody Technique; D006801:Humans; D018579:Patient Selection; D010976:Platelet Count / Q000379:methods*; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000097:blood* / Q000188:drug therapy