Vitamin K deficiency

At birth babies only have a small store of vitamin K which is quickly used up in the first few days of life. This may lead to something called ‘vitamin K deficiency bleeding ‘(VKDB). The blood loss can be from the umbilical cord site, nose, and mouth or into the brain, where it is not visible. When it occurs in the brain it may cause brain damage or death. By giving newborns vitamin K babies can be protected against this disorder

About

• Vitamins K1 (phytonadione)
• Vitamin K2 (menaquinone)

Aetiology

• Vitamin K is a fat-soluble vitamin needed for clotting
• Absorbed in the small intestine and stored in the liver
• Cofactor in the enzymatic carboxylation of glutamic acid residues on prothrombin- complex proteins.

Causes of deficiency

• Poor dietary intake
• Intestinal malabsorption
• Liver disease
• Newborns

Clinical

• Bleeding, bruising, Melena, Retroperitoneal bleed
• Haemorhagic stroke

Investigations

• Prolonged prothrombin time first. Eventually aPTT will be prolonged as well. Factor VIII is not influenced by vitamin K.

Management

• Treat with Oral or IV Vitamin K 1-5 mg which can be given and works within 6 hrs
• Emergency with bleeding that is ever life/limb or sight threatening then give Prothrombin complex concentrates (Beriplex/Octaplex)
• Vitamin K can be given to newborn babies orally or by IM injection

References