title: Immature platelets do not reliably predict platelet recovery in patients with intensive chemotherapy or stem cell transplantation.
abstract: OBJECTIVE
  It has been reported that immature platelets may indicate imminent platelet (PLT) recovery following intensive chemotherapy and/or haematopoietic stem cell transplantation with the perspective to withhold unnecessary transfusions. The objective of our prospective study was to test immature PLTs as measured by two haematology analysers to predict PLT recovery.
  
  
  METHODS
  This study monitored 51 courses of severe thrombocytopenia after chemotherapy in 35 adult haematology/oncology patients starting at a PLT count <70 × 109/l until PLT recovery (>20 × 109/l) or discharge from hospital. Immature platelets as measured by immature platelet fraction (IPF) (Sysmex XE-5000) and retPLT (Abbott CD-Sapphire) as well as reticulocyte and leucocyte count were evaluated regarding their usefulness to predict PLT recovery. Furthermore, the influence of platelet concentrate (PC) transfusions upon IPF and retPLT was assessed.
  
  
  RESULTS
  With beginning of thrombocytopenia, most patients demonstrated elevated IPF% (median 8·6%) and retPLT% (median 6·8%). These elevated values significantly dropped after transfusions of PCs. IPF and retPLT values during nadir and at imminent PLT recovery were largely overlapping and receiver operating characteristics analysis demonstrated poor separation between both clinical situations. A reasonable cut-off could not be established to prospectively predict imminent PLT recovery for either of the parameters investigated.
  
  
  CONCLUSIONS
  Measurements of IPF and retPLT lack predictive power regarding imminent PLT recovery in patients with severe thrombocytopenia following intensive chemotherapy. Decisions regarding prophylactic PC transfusions should not be based on these parameters.
authors.affiliation: Department of Internal Medicine 5 - Haematology & Oncology, University of Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: L
authors.initials: L
authors.lastname: Meintker
authors.affiliation: Department of Internal Medicine 5 - Haematology & Oncology, University of Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: J D
authors.initials: JD
authors.lastname: Fritsch
authors.affiliation: Department of Transfusion Medicine and Haemostaseology, University of Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Ringwald
authors.affiliation: Department of Internal Medicine 5 - Haematology & Oncology, University of Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: S W
authors.initials: SW
authors.lastname: Krause
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D019540:Area Under Curve; D001792:Blood Platelets / Q000166:cytology* / Q000378:metabolism; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000166:cytology; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000188:drug therapy / Q000628:therapy*; D010976:Platelet Count; D011446:Prospective Studies; D012372:ROC Curve; D012156:Reticulocytes / Q000166:cytology; D013921:Thrombocytopenia / Q000209:etiology; D055815:Young Adult
chemical_list: D000970:Antineoplastic Agents
keywords: immature platelet; immature platelet fraction; platelet transfusion; reticulated platelet; thrombocytopenia