Vitamin K participates in the carboxylation of glutamic acid residues in polypeptide chains of certain proteins to form gamma-carboxy glutamic acid (Gla-radicals). Vitamin K belongs to lipophilic and hydrophobical vitamins group. ![]() Dicumarol is a derivative of coumarin, a bitter-tasting but sweet-smelling substance made by plants that does not itself affect coagulation, but when transformed in mouldy feeds or silages by a number of species of fungi, into active dicoumarol, which does affect coagulation, and was discovered in mouldy wet sweet-clover hay, as the cause of a naturally occurring bleeding disease in cattle. It wasn’t before 1939 that the crystals of dicumarol, a natural chemical substance of combined plant and fungal origin, were isolated. Apart from the natural K-Vitamins (K1 and K2), there are a number of naphthoquinone derivatives, which are acquired synthetically and possess similar anti-coagulative effect (Vitamins K 3–K 7). The same year, the American biochemists Binkley and Doisy managed to isolate from the spoilt fish-flour the vitamin K2 or menaquinone with similar to vitamin K1 anti-hemorrhagic properties, but with different absorption profile and a more complex range of activity. In 1939, a group of researchers, under the supervision of the Swiss scientist Karrer, for the first time separated vitamin K1 from the plant alfalfa ( Medicago sativa), under the chemical name of phylloquinone, which is a fat soluble polycyclic aromatic ketone, stable to air and moisture but decomposes in sunlight. During the same period, an outbreak of a cows’ diseases (“disease of sweet clover”) in the northern part of the USA and Canada was found to be associated with consumption of moldy silage from Melilotus (sweet clover) by the animals with clinical signs identical to the previously described hemorrhagic diathesis of chickens. Subsequent feeding with plant products developed a curative effect. The first observations on K vitamins action, namely massive bleeding into the subcutaneous tissue, muscles and other organs, were observed in the 1920’s and 1930’s in animals (chickens and birds) fed with cholesterol/fat-deficient food. ![]() The aim of this paper is to perform a thorough literature review concerning all types of artificial vitamin K-dependent coagulopathies and to present representative clinical cases from medical practice. Even though such cases are not frequent, physicians can describe similar reports from their personal experience. Physicians occasionally come across with cases of vitamin K-dependent coagulopathy of quite different origin: not reported use of VKA by patients with psychiatric disorders accidental use of indirect anticoagulants instead of other prescribed medication in cases of senile amnesia excessive use of VKA intoxications with rodenticide-poisons containing VKA illegal cases of VKA usage with the purpose of murder or suicide. Vitamin K deficiency can be due to deficient biosynthesis in the intestinal tract that leads to deficient bioavailability in various pathological situations such as: medicine induced intestinal dysbacteriosis, especially after antibiotic treatment enteropathies accompanied by heavy diarrhea mechanical jaundice with acholia that leads to reduction or absence of bile secretion in the intestinal tract prematurity of the newborns associated with subnormal synthesis of vitamin K in intestinal tract severe liver disease (acute dystrophies, hepatitis, cirrhosis) autoimmune disorders due to double antiviral therapy with Peginterferon and Ribavirin in patients with hepatitis C virus infection. Vitamin K-dependent coagulopathies are rather common in clinical practice, especially in cases of overdose of orally prescribed anticoagulants of indirect-action, also known as the vitamin K antagonists (VKA). Reasons for vitamin K antagonists–dependent coagulopathy cases With early diagnosis and prescription of appropriate therapy, prognosis is favorable. Even when pathological vitamin K deficiency is not determined, appropriate and urgent medical treatment is necessary: administration of fresh frozen plasma or concentrated factors of the prothrombin complex, administration of vitamin K remedies along with symptomatic therapy. Differential diagnosis is primarily based on patient statements before additional causes of vitamin K deficiency are explored. ![]() This article discusses different types of acquired vitamin K-dependent coagulopathy. Rodenticide-poisoning (coumarins, warfarins) via food or occupational accidents are difficult to diagnose. Physicians often come across with cases of vitamin K antagonists–dependent coagulopathy for reasons such as accidental use of the vitamin K antagonists (VKA), excessive administration of prescribed anticoagulants of indirect action or not reported administration of vitamin K antagonists due to memory impairment and/or other mental disorders, even deliberate use thereof (attempt to murder or suicide).
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