OBJECTIVETo investigate the clinical manifestations, pathologic features and laboratory findings in two Proteus syndrome patients with giant hemangiomas in the spleen and chronic DIC.

METHODSUltrasound imaging and magnetic resonance imaging (MRI) were used for analysing the characteristics of the giant hemangiomas in the spleen. The spleen specimen was examined pathologically for the feature of the hemangioma. Homostatic tests were performed by routine laboratory methods.

RESULTSTwo Proteus syndrome patients with giant hemangiomas in the spleen causing chronic DIC (Kasabach-Merritt syndrome) were first reported. They were recovered after splenectomy.

CONCLUSIONProteus syndrome when accompanied giant hemangioma could cause chronic DIC. Significantly decreased plasma fibrinogen level in this case might be helpful for the differential diagnosis from DIC caused by other diseases.