title: Effectiveness of Pooled Platelet Transfusion in Concordant and Discordant Groups among Dengue Patients.
abstract: BACKGROUND
  Dengue affects more than 50 million people per year and is one of the most common causes of severe thrombocytopaenia. Thrombocytopaenia is a common complication of dengue and other viral fevers apart from malaria, typhoid, leptospirosis, leukaemia and megaloblastic anaemia. A platelet count of <20,000/μl is characteristically seen in dengue haemorrhagic fever and dengue fever. It results from immune complex mediated platelet destruction or bone marrow suppression. Severe thrombocytopaenia <10,000/μl is one of the indications for prophylactic platelet transfusion therapy to prevent haemorrhage.
  
  
  OBJECTIVE
  To evaluate the effectiveness of transfusion of ABO compatible and ABO incompatible pooled platelet units in severe thrombocytopaenia cases.
  
  
  METHODS
  In this study ABO compatible and incompatible pooled platelet units were transfused to serologically confirmed dengue cases having thrombocytopaenia with or without bleeding manifestations. Each of the adult patients received 4-6 units of pooled platelet concentrates prepared from random donor whole blood suspended in plasma for severe thrombocytopaenia. Pre and post transfusion platelet counts were compared. Children aged less than 12 years, pregnant women and patients with splenomegaly those on ayurvedic and homeopathic therapy, recipients of packed red cells on the same day of platelet transfusion and recipients of multiple platelet transfusions within 24 hours were excluded from the study.
  
  
  RESULTS
  The median post transfusion platelet increments (PPI) and corrected count increments (CCI) at 4hour post transfusion were 25,000/μL (5,000-80,000/μL) and 18,000/μL (range 8,000/μL- 47,500/μL) respectively among the responders. Median PPI and CCI at 24 hours were 45,000/μL and 28,863/μL among the responders. The median CCI at 4 hour post transfusion among the non-responders was 850/μL and at 24hours was 1,425/μL. At 24 hours responders showed significantly higher PPI as compared to non responders. The average platelets transfused were 4units in case of responders and 8 units in case of non-responders.
  
  
  CONCLUSIONS
  ABO identical and compatible pooled platelet transfusions were more successful in increasing the post transfusion platelet counts as compared to ABO incompatible pooled platelets.
authors.affiliation: Assistant Professor, Department of Pathology, Sapthagiri Institute of Medical Sciences and Research Centre , Bengaluru, Karnataka, india .
authors.forename: Amoolya
authors.initials: A
authors.lastname: Bhat
authors.affiliation: Professor and Head, Department of Pathology, Sapthagiri Institute of Medical Sciences and Research Centre , Bengaluru, Karnataka, india .
authors.forename: Vijaya
authors.initials: V
authors.lastname: Chowdappa
authors.affiliation: Assistant Professor, Department of Pathology, Sapthagiri Institute of Medical Sciences and Research Centre , Bengaluru, Karnataka, india .
authors.forename: Smita Surendra
authors.initials: SS
authors.lastname: Masamatti
keywords: ABO compatible; ABO identical; Dengue; Platelet transfusion; Pooled