Prospective observational study of low thresholds for platelet transfusion in adult dengue patients.

Background: The practice of platelet (PLT) transfusions has been adopted into the standard clinical practice in many dengue-endemic countries. Because many patients were found to have received unnecessary PLT transfusions, the development of guidelines for the management of dengue patients with thrombocytopenia has become a necessity.
Study Design and Methods: An emergency department-based prospective observational study was conducted in Martinique during a dengue outbreak in adult patients presenting with an acute febrile illness. Patients with severe bleeding and/or who underwent invasive intensive care procedures or emergency surgery were given PLT transfusion to achieve PLT counts of more than 50 x 10(9)/L. PLT transfusion was also considered for patients with PLT counts of less than 5 x 10(9)/L and for those with associated risk factors and PLT counts of less than 20 x 10(9)/L.
Results: A total of 350 patients were admitted with confirmed dengue infections. Most of them had secondary serotype-2 infections. PLT counts of less than 50 x 10(9)/L were recorded in 165 patients (47.1%). PLT transfusion was administered to 9 patients with thrombocytopenia. The indications included severe bleeding (5 cases), invasive procedures (3 cases), emergency surgery (1 case), and/or associated risk factors (2 cases). The median time duration from the onset of fever to PLT transfusion was 6 days (range, 4-10 days). The median amount of PLTs transfused was 3.66 x 10(11) (range, 2.8 x 10(11)-13.2 x 10(11)). The median PLT yield was +12.4% (range, -3.9% to +67.1%). Three patients died. All other patients recovered during the second week after the onset of fever.
Conclusion: A restrictive strategy for PLT transfusion based on clinical features and low PLT count thresholds proved to be feasible and safe for adult dengue patients.