Hemolytic uremic syndrome complicated by vitamin K deficiency

A 5-year-old child with hemolytic uremic syndrome developed bleeding due to vitamin K deficiency 9 days after the onset of a diarrheal prodrome. Vitamin K deficiency was documented by rapid correction of the PT and PTT and cessation of bleeding following administration of vitamin K, as well as by the detection of noncarboxylated prothrombin in plasma. The case is instructive because it suggests that previously healthy older children who become acutely ill may develop vitamin K deficiency more rapidly than heretofore has been appreciated.