Vitamin K Deficiency Bleeding: A Case Revealed by Intracranial Haemorrhage

Intracranial haemorrhage in early childhood is associated with a wide variety of causes such as trauma, vascular malformations (aneurysm and arteriovenous malformation), haemorrhagic infarction, brain tumours or blood coagulation disorders (congenital or acquired from coagulation factors). Vitamin K deficiency causes blood coagulation disturbances that can lead to intracranial haemorrhage [1]. The classic role of vitamin K is its anti-haemorrhagic function which is necessary for the synthesis in the liver of the functional forms of prothrombin (factor II) and factors VII, IX and X. After secretion in the blood, these four Vitamin K – dependent factors participate in coagulation. A series of complex events leads to the conversion of fibrinogen to fibrin and the formation of a haemo static plug. Biochemically, the roles of vitamin K are multiple. It allows the carboxylation of glutamate residues into gamma-carboxyglutamate necessary for hepatic synthesis of vitamin K-dependent coagulation factors, and also for the synthesis of osteocalcin and other proteins involved in the vascular structure. The consequences of vitamin K deficiency for haemostasis are an inability to synthesize functional molecules of factors II, VII, IX and X resulting in a hypocoagulable state [2]. In the event of vitamin K deficiency, the liver synthesizes non-functional coagulation factors called PIVKA (Protein Induced by Vitamin K Absence or Antagonists). These proteins cannot fix calcium and act by inhibiting coagulation, which leads to a haemorrhagic syndrome. Haemorrhagic disease of the newborns was first described by Townsend in 1894. This terminology, however, is not concise because infants can also be affected and moreover it is not informative on the cause of the haemorrhagic disease. This is why the term haemorrhagic disease due to vitamin K deficiency seems more appropriate. It is a disease that has become rare in the industrialized countries thanks to the prophylaxis systematically proposed at birth and continued if necessary during the whole period of exclusive breastfeeding. The placental passage of vitamin K is weak and newborns have little hepatic reserve. All newborns are therefore deficient at birth. In addition,vitamin Kis low in breast milk. Breastfed newborns are therefore at risk of vitamin K deficiency and haemorrhagic disease. We report the case of an infant with late haemorrhagic disease due to vitamin K deficiency revealed by intracranial haemorrhage.