Kasabach-Merritt phenomenon (KMP) is characterised by thrombocytopenia, microangiopathic haemolytic anaemia and consumptive coagulopathy that can lead to life-threatening bleeding, in the context of an enlarging vascular tumour (1). KMP usually develops in infancy and is associated with significant morbidity and mortality. Potentially fatal complications associated with KMP include haemorrhage, cardiac failure and invasion of vital structures by the lesion. The mortality rate is reported as high as 30% (2). The first case of KMP was reported in 1940 by Kasabach and Merritt, who described a case of consumptive coagulopathy associated with a hemangioma (3). However, it is now recognised that KMP is usually associated with Kaposiform hemangioendothelioma (KHE) and tufted angioma, rather than the classic involuting hemangioma of infancy (4).Fortunately, KMP is rare, affecting <1% of all children with vascular tumours. The optimum treatment of KMP has not been established, and its management can be very difficult. It often involves a multimodal approach, with many disciplines involved. In this article, we review the experience of managing KMP in a single institution. AbstractObjective: Kasabach-Merritt phenomenon (KMP) can lead to life-threatening bleeding, and its optimum treatment has not been established. We review the experience of managing KMP in a single institution. Methods: A retrospective chart review on all children with KMP treated at the Hospital for Sick Children, Toronto, over an 18 yr period was carried out. Results: All 15 patients had profound thrombocytopenia and hypofibrinogenemia at presentation, half had bleeding symptoms, and three had cardiac failure. All patients received corticosteroids. Five responded to steroids alone, given for an average of 13 wk, increasing platelets to >20 · 10 9 ⁄ L at a mean of 6.2 d and fibrinogen >1 g ⁄ dL at 25.6 d. Ten patients received at least one other therapeutic modality in addition to steroids, including vincristine, interferon, anti-platelet agents and pentoxifylline. Five patients received vincristine, for a mean of 6 wk, with two patients responding. Eight patients received interferon, for a mean of 4 months, with two patients responding. Overall, the mean time to increasing platelets >20 · 10 9 ⁄ L was 56 d, to >150 · 10 9 ⁄ L was 88 d and fibrinogen >1 g ⁄ dL 49 d. Ten patients showed a partial response to embolisation, with a mean of 2.8 procedures performed. Thrombotic complications occurred in 7%. Twelve patients remain alive, with relapse in six patients, all treated successfully. One patient died, and two patients have been lost to follow-up. Conclusion: KMP is a rare condition, with significant morbidity and mortality. The therapeutic approach should include a multidisciplinary team and consensus on guidelines.