title: Autoimmune Thrombocytopenia Complicated by EDTA- and/or Citrate-Dependent Pseudothrombocytopenia.
abstract: BACKGROUND
  Pseudothrombocytopenia (PTCP) is a well-known phenomenon. However, confusion may occur due to unusual characteristics.
  
  
  METHODS
  Two patients with autoimmune thrombocytopenia (ITP) and long-lasting PTCP are described. Initially, only the diagnosis of ITP was confirmed. During observation, discrepancies were recognized between clinical findings and platelet counts. Re-examination resulted in the additional diagnosis of EDTA-dependent PTCP. Subsequently, the latter diagnosis was changed to citrate-dependent PTCP in both cases. Interestingly, PTCP was observed to change again and became recognizable in citrate or heparin, and only during the first 20-30 min following phlebotomy in EDTA specimens.
  
  
  CONCLUSIONS
  The incidence of concomitant ITP with PTCP might be higher than previously reported, and PTCP may have variable dynamics and characteristics.
authors.affiliation: Institute for Transfusion Medicine, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Abdulgabar
authors.initials: A
authors.lastname: Salama
keywords: Citrate-dependent; EDTA-dependent; Heparin-dependent; ITP; Pseudothrombocytopenia