Platelet Kinetics of Prophylactic Platelet Transfusion in Adult Dengue

Background:

Thrombocytopenia is common in dengue. Prophylactic platelet transfusion is widely practiced but platelet response kinetics in adult patients is not well described.

Methods:

A multicenter, open-label, randomized study of prophylactic platelet transfusion versus supportive care in adult dengue patients with platelet counts ≤20x10³/µL was conducted in 5 hospitals in Singapore and Malaysia. Platelet outcomes studied were: platelet increment at 1, 12 and 24 hours post-transfusion, daily platelet count until discharge or study day 7, and median time to platelet count >50x10³/µL.

Results:

182 patients were randomized to supportive care and 187 to prophylactic platelet transfusion with similar baseline age, gender, co-morbidities, clinical bleeding, warning signs and disease severity between the two groups. The median platelet increment (x10³/µL) among transfused patients at 1 hour was 16 (interquartile range [IQR], 8-24), 12 hours was 13 (IQR, 5-22) and 24 hours was 25 (IQR, 13-41). Median platelet count change (x10³/µL) was significantly lower in the non-transfused than transfused group on study day 2 (5 [IQR, -1-12] versus 13 [IQR, 3-22], p<0.001), but was similar from study day 3 (27 [IQR, 12-47] versus 28 [IQR, 15-49], p=0.500) to day 7 (111 [IQR, 47-299] versus 119 [IQR, 64.5-186], p=0.860). By study day 7, 100 (55.0%) of supportive care and 109 (58.3%) of transfused group patients had platelet counts >50x x10³/µL (p=0.530). Median time to platelet count >50x x10³/µL was 4 days in both groups (p=0.389). More adverse events occurred in the prophylactically transfused than non-transfused group (13 [6.9%] versus 2 [1.1%], p=0.006).

Conclusion:

Platelet response to prophylactic platelet transfusion was transient. Adverse events were more common among platelet-transfused patients.