EC Paediatrics

Factor II is a liver-synthesized glycoprotein, a zymogen of a serine protease, and one of the vitamin K-dependent coagulation factors. Factor II deficiency is a rare inherited disorder transmitted in an autosomal recessive manner.

We present the case of a 6-and-a-half-year-old child hospitalized for cutaneous hemorrhagic syndrome. The family history revealed first-degree consanguinity and bleeding disorders in the siblings. The clinical examination showed bruises of various sizes on the extremities. Biological tests indicated a normal blood count, a low prothrombin rate of 30%, and a prolonged activated partial thromboplastin time of 60 seconds. Coagulation factor assays revealed severe factor II deficiency at 3%, with normal levels of factors V, VII, and X, and negative anti-factor II antibodies. Liver and immunological tests were negative. A family investigation showed similar abnormalities in the brothers, while the parents had factor II levels of 50%. The child did not receive specific treatment, with transfusions of fresh frozen plasma considered only in case of active bleeding.

Factor II deficiency is extremely rare, with an estimated prevalence of homozygous forms at 1 in 2,000,000. Clinical signs include epistaxis, menorrhagia, gingivorrhagia and ecchymosis. Diagnosis is based on prolonged prothrombin and activated partial thromboplastin times, and low factor II coagulant activity. Treatments include prothrombin complex concentrates and fresh frozen plasma. The prognosis is good with early diagnosis and appropriate treatment.

This case report highlights the importance of early detection and appropriate management of factor II deficiency, especially in settings with consanguinity. Close monitoring and personalized management of bleeding episodes are crucial for improving patient prognosis. Genetic counseling and raising clinicians' awareness of rare coagulation disorders are essential to optimize management and prevent serious complications.

 Keywords: Factor II Deficiency; Hemorrhagic Syndrome; Coagulation Disorder; Genetic Counseling

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