Episode of Kasabach-Merritt phenomenon following Japanese encephalitis vaccination: Case report.

Kasabach-Merritt phenomenon (KMP) is a rare potentially life-threatening consumptive coagulopathy characterized by thrombocytopenia and hypofibrinogenemia occurring associated with the vascular tumors kaposiform hemangioendothelioma (KHE) and tufted angioma (TA). A 10-month old male infant, diagnosed with KHE on his left leg, underwent a rapid increase of the lesion and severe thrombocytopenia, one day after the first dose of inactivated Japanese encephalitis (JE) vaccination. The episode of KMP was treated successfully by steroid. KMP is a rare complication of vaccination that physicians should be aware of. Giving up the following vaccination to provide the recurrence of KMP is not recommended.