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Semin Thromb Hemost 2019 Jan 10. Epub 2019 Jan 10.

Department of Haematology, NSW Health Pathology, Royal Prince Alfred Hospital, Camperdown, New South Wales, Australia.

The activated partial thromboplastin time (APTT) assay is a very common coagulation test, used for several reasons. The test is conventionally used for assessing the contact factor (intrinsic) pathway of blood coagulation, and thus for screening deficiencies in this pathway, most typically factors VIII, IX, and XI. The APTT is also sensitive to contact factor deficiencies, including factor XII, prekallikrein, and high-molecular-weight kininogen. Read More

Acta Clin Belg 2019 Jan 8:1-5. Epub 2019 Jan 8.

a Department of Ageing & Health , Guy's & St. Thomas' NHS Trust , London , UK.

Introduction: Vitamin K plays an important role in blood coagulation. Diet is the main source of vitamin K and body stores are depleted in days, hence deficiency is common in malnourished older people. A high proportion of people who sustain a hip fracture are already malnourished, compounded by fasting for surgery which might further increase deficiency. Read More

Dermatology 2019 Jan 3:1-10. Epub 2019 Jan 3.

Department of Nephrology and Organ Transplantation, Center for Rare Renal Disease, University Hospital of Toulouse, Toulouse,

Background: Calciphylaxis (CPX) is a rare and life-threatening disease characterized by vascular calcification and development of painful and necrotizing skin lesions with a challenging management. Mechanisms of CPX are complex and include an imbalance between vascular calcification promoters and inhibitors, and frequently vitamin K deficiency.

Objectives: To describe the various presentations and identify predictive factors of death in patients with CPX. Read More

Hosp Pediatr 2019 Jan;9(1):55-60

Department of Women's and Children's Health, Dunedin School of Medicine,

Since its initial discovery almost a century ago, vitamin K has been labeled as both lifesaving and malignancy causing. This has led to debate of not only its use in general but also regarding its appropriate dose and route. In this article, we review through a historical lens the past 90 years of newborn vitamin K from its discovery through to its modern use of preventing vitamin K deficiency bleeding (VKDB). Read More

Nephrol Dial Transplant 2018 Dec 26. Epub 2018 Dec 26.

Division of Nephrology and Infectious Diseases, Department of Internal Medicine, AZ Sint-Jan Brugge, Brugge, and Ghent University, Ghent, Belgium.

The cardinal biological role of vitamin K is to act as cofactor for the carboxylation of a number of vitamin K-dependent proteins, some of which are essential for coagulation, bone formation and prevention of vascular calcification. Functional vitamin K deficiency is common and severe among dialysis patients and has garnered attention as a modifiable risk factor in this population. However, no single biochemical parameter can adequately assess vitamin K status. Read More

J Crit Care 2019 Feb 28;49:105-109. Epub 2018 Oct 28.

Institution of Clinical Sciences Lund, Medical Faculty, Lund University, S-22185 Lund, Sweden.; Department of Intensive and Perioperative Care, Skane University Hospital, S-22185 Lund, Sweden. Electronic address:

Background: Vitamin K is a cofactor for proteins involved in cardiovascular health, bone metabolism and cancer. Measuring uncarboxylated prothrombin, also termed as "protein induced by vitamin K absence or antagonism for factor II (PIVKA-II)", has been used to assess vitamin K status. High levels may indicate vitamin K deficiency. Read More

Clin Transl Gastroenterol 2018 Oct 15;9(10):197. Epub 2018 Oct 15.

Digestive & Liver Disease Unit, Sant'Andrea Hospital, "La Sapienza", Rome, Italy.

Background: Osteopathy is common in patients with chronic pancreatitis (CP), but previous studies carry several limitations. Vitamin K is essential for bone metabolism, but its role in this setting has never been investigated. Our aim is to assess the prevalence of osteoporosis and osteopenia in CP patients, and to investigate the association between osteopathy and CP features and nutritional parameters, especially vitamin D and K levels. Read More

Can Fam Physician 2018 Oct;64(10):736-739

Member of the Maternity and Newborn Care Program Committee of the College of Family Physicians of Canada.

Newborns are at risk for vitamin K deficiency bleeding (VKDB) caused by inadequate prenatal storage and deficiency of vitamin K in breast milk. Systematic review of evidence to date suggests that a single intramuscular (IM) injection of vitamin K at birth effectively prevents VKDB. Current scientific data suggest that single or repeated doses of oral (PO) vitamin K are less effective than IM vitamin K in preventing VKDB. Read More

Pediatr Ann 2018 10;47(10):e383-e384

Pediatr Int 2018 Oct 8;60(10):991-992. Epub 2018 Oct 8.

Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.

J Obstet Gynaecol Res 2018 Sep 25. Epub 2018 Sep 25.

Department of Pediatrics, Iwate Medical University School of Medicine, Morioka, Japan.

Vitamin K deficiency in pregnant women causes intracranial hemorrhage (ICH) in fetuses. Fetal ICH frequently causes life-threatening and persistent neurological damage. However, indicators for preventing fetal ICH are not established. Read More

Hematology 2019 Dec 7;24(1):97-102. Epub 2018 Sep 7.

a Department of Hematology , All India Institute of Medical Sciences , New Delhi , India.

Objective: Factor VII deficiency is the commonest of the rare bleeding disorders with limited knowledge on clinical profile. The objective of this study was to study the prevalence and clinico-hematological profile of factor VII-deficient patients.

Methods: It is a retrospective observational study of probable inherited factor VII deficiency covering 18 months. Read More

J Nutr Sci Vitaminol (Tokyo) 2018 ;64(4):243-250

Department of Home Economics, Aichi Gakusen University.

Previous studies have shown that α-tocopherol intake lowers phylloquinone (PK) concentration in some extrahepatic tissues in rats. The study's aim was to clarify the effect of α-tocopherol intake on vitamin K concentration in bone, as well as the physiological action of vitamin K. Male Wistar rats were divided into 4 groups. Read More

Nutrients 2018 Aug 12;10(8). Epub 2018 Aug 12.

Department of Biomedical and Molecular Science, Queen's University, Kingston, ON K7L 3V6, Canada.

The purpose of this review is to summarize the research to date on the impact of chronic kidney disease (CKD) on the vitamin K metabolome. Vitamin K-dependent proteins contribute to cardiovascular disease (CVD) prevention via the prevention of ectopic mineralization. Sub-clinical vitamin K deficiency is common in CKD patients, and evidence suggests that it may contribute to the CVD burden in this population. Read More

Pediatr Ann 2018 Aug;47(8):e334-e338

Vitamin K refusal and associated sequelae of vitamin K deficiency bleed (VKDB) in the newborn period is becoming a more common occurrence. We present six recent cases from a 4-month period in 2017 of parent refusal of vitamin K and describe the reasons for refusal and the clinical outcomes of these infants. There have been a number of case reports citing the rising incidence of VKDB and the reasons why parents refuse. Read More

Clin Appl Thromb Hemost 2018 Aug 13:1076029618792302. Epub 2018 Aug 13.

5 Faculty of Medicine, Division of Pediatric Neurology, Department of Pediatrics, Erciyes University, Kayseri, Turkey.

Intracranial hemorrhage due to vitamin K deficiency is a serious disease that can lead to morbidity, mortality, and mental retardation. Our goal in this study is to determine the frequency of VKORC1-1639 G>A polymorphism in patients who have undergone intracranial hemorrhage due to vitamin K deficiency bleeding (VKDB). To study VKORC1-1639 G>A polymorphism, blood was drawn from patients (n = 51, age 8:0 ± 6:5 years) followed at the Pediatric Neurology and Hematology section, Faculty of Medicine, Erciyes University, between 1990 and 2016, diagnosed with VKDB as idiopathic or from patients diagnosed with intracranial hemorrhage due to secondary vitamin K deficiency and also from volunteers (n = 51, age 11 ± 4. Read More

Clin Kidney J 2018 Aug 10;11(4):528-529. Epub 2017 Nov 10.

Canberra Hospital Renal Unit, Garran, ACT, Australia.

Calciphylaxis has high mortality. Vitamin K deficiency is common in haemodialysis patients and may be a trigger for calciphylaxis due to its role in activating matrix Gla protein (a tissue inhibitor of calcification). We report the case of a 43-year-old female haemodialysis patient who developed calciphylaxis. Read More

Ophthalmologe 2018 Aug 2. Epub 2018 Aug 2.

Augenklinik und Poliklinik, Universitätsklinikum Würzburg, Josef-Schneider-Str. 11, 97080, Würzburg, Deutschland.

Unilateral retinal hemorrhage in infants can be caused by vitamin K deficiency. The case described here with fatal outcome presents the medical history of a 2-month-old infant with vitamin K deficiency bleeding caused by the refusal of vitamin K prophylaxis by the parents. Ocular signs were unilateral intraretinal hemorrhage with Roth spots and preretinal hemorrhage over the complete back of the eye. Read More

Front Aging Neurosci 2018 16;10:213. Epub 2018 Jul 16.

Montreal Heart Institute Research Centre, Montreal, QC, Canada.

Initially discovered for its role in blood coagulation, there is now convincing evidence that vitamin K (VK) has important actions in the nervous system. In brain, VK is present in the form of menaquinone-4 (MK-4), a byproduct of the main dietary source, phylloquinone. It contributes to the biological activation of various proteins (i. Read More

Biochim Biophys Acta Gen Subj 2018 Jul 20;1862(10):2226-2235. Epub 2018 Jul 20.

Tongji School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China. Electronic address:

Protein misfolding and aggregation are associated with amyloidosis. The toxic aggregation of amyloid-β 1-42 (Aβ42) may disrupt cell membranes and lead to cell death and is thus regarded as a contributing factor in Alzheimer's disease (AD). 1,4-naphthoquinone (NQ) has been shown to exhibit strong anti-aggregation effects on amyloidogenic proteins such as insulin and α-synuclein; however, its high toxicity and poor solubility limit its clinical application. Read More

Case Rep Pediatr 2018 24;2018:7041204. Epub 2018 Jun 24.

Division of Hematology and Oncology, Department of Pediatrics, Phramongkutklao Hospital and College of Medicine, Bangkok, Thailand.

Vitamin K deficiency bleeding (VKDB) is a life-threatening condition and can be found in children as early as neonatal period with early onset intracranial hemorrhage (ICH). Here, we reported a 1-year-old boy who initially presented with intracranial hemorrhage secondary to vitamin K deficiency since 3 months of age and later found to have XL-CGD which was complicated by malabsorption due to severe vaccine-associated mycobacterial disease. Read More

Dtsch Arztebl Int 2018 Jun;115(24):416

Clin Chim Acta 2018 Oct 26;485:272-274. Epub 2018 Jun 26.

University of Virginia Department of Pathology, Charlottesville, VA, United States. Electronic address:

Background: Vitamin K is a vital component within both the intrinsic and extrinsic coagulation cascade as certain factors (II, VII, IX, X and protein C and S) utilize vitamin K as a cofactor during post translational modification. Deficiency of vitamin K can result in the inability to properly form blood clots, both in vivo and in vitro, due to reduced vitamin K dependent factor levels and function. Vitamin K deficiency can result from congenital causes, such as VKOR or CYP2C9 mutations, or acquired causes, such as nutritional deficiencies, antibiotic therapy, or supra-therapeutic warfarin dosing. Read More

Maturitas 2018 Jul 30;113:73-79. Epub 2018 Apr 30.

Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands.

Objective: We examined the association between vitamin K status and physical functioning over 13 years in the Longitudinal Aging Study Amsterdam.

Study Design: Longitudinal cohort study of 633 community-dwelling adults from the Longitudinal Aging Study Amsterdam (LASA) aged 55-65 years (54% women).

Main Outcome Measures: At baseline (2002-2003), plasma desphospho-uncarboxylated matrix Gla protein (dp-ucMGP) was measured with a sandwich ELISA as a marker of vitamin K status. Read More

Nutrients 2018 Jun 6;10(6). Epub 2018 Jun 6.

Department of Biochemistry, Cardiovascular Research Institute Maastricht, University Maastricht, 6200 MD Maastricht, The Netherlands.

Objective: In the past decades, an increased interest in the roles of vitamin D and K has become evident, in particular in relation to bone health and prevention of bone fractures. The aim of the current study was to evaluate vitamin D and K status in children with low-energy fractures and in children without fractures.

Methods: The study group of 20 children (14 boys, 6 girls) aged 5 to 15 years old, with radiologically confirmed low-energy fractures was compared with the control group of 19 healthy children (9 boys, 10 girls), aged 7 to 17 years old, without fractures. Read More

Inflamm Bowel Dis 2018 May 28. Epub 2018 May 28.

Department of Paediatric Gastroenterology and Metabolic Diseases, Poznan, Poland.

J Neonatal Perinatal Med 2018 ;11(2):191-194

Department of Perinatal and Neonatal Medicine, Aichi Medical University Sciences, Karimata, Nagakute, Aichi, Japan.

We present here a late preterm infant with extensive brain lesions resulting from vitamin K deficiency. A female infant was born after 35 weeks of gestation by emergent cesarean section because of non-reassuring fetal status. Her mother had severe eating disorder and recurrent vomiting since early pregnancy. Read More

Am J Emerg Med 2017 04 16;35(4):660.e1-660.e2. Epub 2014 Oct 16.

Good Samaritan Hospital Medical Center, 1000 Montauk Highway, West Islip, NY 11795.

J Pediatr Surg 2018 Nov 1;53(11):2245-2249. Epub 2018 May 1.

Department of Pediatric Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1, Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.

Background/purpose: Intracranial hemorrhage (ICH) is a severe complication of biliary atresia (BA). We aimed to compare the clinical data of BA patients with and without ICH.

Methods: Sixty-three BA patients who underwent Kasai portoenterostomy were included in this study. Read More

Crit Rev Biotechnol 2018 May 24:1-19. Epub 2018 May 24.

a School of Chemical and Biomolecular Engineering , University of Sydney , Sydney , NSW , Australia.

The primary objective of this review is to propose an approach for the biosynthesis of phylloquinone (vitamin K) based upon its known sources, its role in photosynthesis and its biosynthetic pathway. The chemistry, health benefits, market, and industrial production of vitamin K are also summarized. Vitamin K compounds (K vitamers) are required for the normal function of at least 15 proteins involved in diverse physiological processes such as coagulation, tissue mineralization, inflammation, and neuroprotection. Read More

Am J Hypertens 2018 Aug;31(9):988-994

Department of Medicine and Radiology, Corporal Michael J. Crescenz VAMC, Philadelphia, Pennsylvania, USA.

Background: Large artery stiffening is increased in advanced chronic kidney disease (CKD) but likely develops progressively in earlier stages of CKD. Active matrix Gla-protein (MGP) is a potent vitamin K-dependent inhibitor of vascular calcification. A recent animal model demonstrated intrinsic abnormalities in vitamin K metabolism even in early CKD, but whether early human CKD is associated with vascular vitamin K deficiency is unknown. Read More

Mol Med Rep 2018 Jul 27;18(1):3-15. Epub 2018 Apr 27.

Department of Physiology, Dalian Medical University, Dalian, Liaoning 116044, P.R. China.

In postmenopausal women and elderly men, bone density decreases with age and vascular calcification is aggravated. This condition is closely associated with vitamin K2 deficiency. A total of 17 different vitamin K‑dependent proteins have been identified to date. Read More

Clin Lab 2018 Apr;64(4):413-424

Background: Vitamin K (VK) is a co-factor of the γ-glutamyl carboxylase that catalyzes the conversion of glutamate residues to γ-carboxyglutamate in VK-dependent proteins. The carboxylation reaction imparts the essential calcium-binding residues for the biological function of several proteins involved in the process of coagulation and bone metabolism. VK deficiency is frequently encountered in newborns and can lead to fatal hemorrhagic complications. Read More

AJP Rep 2018 Apr 12;8(2):e68-e70. Epub 2018 Apr 12.

Department of Postgraduate Education and Training, National Center for Child Health and Development, Tokyo, Japan.

Severe protein C (PC) deficiency leads to purpura fulminans and stroke in newborns. However, the clinical impact of plasma PC activity on the development of neonatal cerebral disease remains elusive. We report a case of hemorrhagic stroke associated with neonatal asphyxia and severe PC deficiency. Read More

BMC Pediatr 2018 04 9;18(1):130. Epub 2018 Apr 9.

Department of Biochemistry, Adnan Menderes University Medical Faculty, Aydın, Turkey.

Background: In children diagnosed with celiac disease, fat soluble vitamin levels were aimed to be evaluated and it was intended to determine whether fat soluble vitamin levels were needed to be assessed routinely in these patients during diagnosis.

Methods: Between May 2015-May 2016, diagnosis symptoms of celiac patients (CD) in newly diagnosed pediatric group were questioned, fat soluble vitamin levels simultaneous with intestinal biopsies were evaluated. Vitamin levels were compared with those of healthy control group. Read More

Pharmazie 2018 04;73(4):234-240

Vitamin (V) K deficiency may cause severe bleeding tendencies, which necessitates extreme caution. We report a case of a 30-year-old man diagnosed with VK deficiency of unknown etiology. He was treated with intravenous menatetrenone three times a week in an outpatient setting for about 1 year and 9 months. Read More

Nagoya J Med Sci 2018 02;80(1):11-20

Department of Healthcare Administration, Nagoya University Graduate School of Medicine, Nagoya, Japan.

Vitamin K deficiency bleeding (VKDB) is a preventable cause of infant mortality and long-term morbidity through the world. This study aimed to demonstrate the costs of VKDB treatment estimated from the hospital records in Tashkent, Uzbekistan, as well as the prophylaxis costs for mass vitamin K medication. Subjects were 50 patients with no operation and 50 patients who had received a brain operation, consecutively enrolled from 180 cases diagnosed at Republican Research Center of Emergency Medicine in 2014. Read More

Pan Afr Med J 2017;28:150. Epub 2017 Oct 18.

Paediatric Medical Emergency Department, Children's Hospital, Faculty of Medicine and Pharmacy, University Mohammed V, Rabat, Morocco.

Ital J Pediatr 2018 Mar 14;44(1):36. Epub 2018 Mar 14.

Pediatric and Infectious Disease Unit, Bambino Gesu' Children's Hospital, IRCCS, Piazza Sant'Onofrio 4, Rome, Italy.

Background: Vitamin K, a fat soluble vitamin, is a necessary cofactor for the activation of coagulation factors II, VII, IX, X, and protein C and S. In neonatal period, vitamin K deficiency may lead to Vitamin K Deficiency Bleeding (VKDB).

Case Presentation: We present the case of a 2 months and 20 days Caucasian male, presented for bleeding from the injections sites of vaccines. Read More

Pediatr Emerg Care 2018 Mar 12. Epub 2018 Mar 12.

Although there are several reports of intracranial hemorrhage associated with vitamin K deficient bleeding, there are few reported cases of extracranial manifestations, specifically involving the thymus. Here, we discuss the unique case of a 4-week-old infant presenting with scrotal discoloration, respiratory distress, and widened mediastinum, found to have thymic hemorrhage related to confirmed coagulopathy secondary to late-onset vitamin K deficiency bleeding of the newborn. Read More

Curr Opin Pulm Med 2018 05;24(3):287-295

Department of Pharmacology and Toxicology, Faculty of Health, Medicine and Life Science, Maastricht University, Maastricht.

Purpose Of Review: Fibrosing interstitial pneumonias are associated with various stages of fibrosis. The cause of this group of syndromes remains largely unknown. For most of these diseases, a genetic basis, environmental factors and certain triggers have been suggested as possible risk factors. Read More

Int J Pharm 2018 Apr 19;541(1-2):56-63. Epub 2018 Feb 19.

School of Pharmacy, Queen's University, Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, United Kingdom. Electronic address:

Vitamin K deficiency within neonates can result in vitamin K deficiency bleeding. Ensuring that newborns receive vitamin K is particularly critical in places where access to health care and blood products and transfusions is limited. The World Health Organization recommends that newborns receive a 1 mg intramuscular injection of vitamin K at birth. Read More

Cochrane Database Syst Rev 2018 02 5;2:CD008342. Epub 2018 Feb 5.

Pediatrics Division of Newborn Medicine, University of Pittsburgh Medical Center, 300 Halket Street, Pittsburgh, Pennsylvania, USA, 15219.

Background: Vitamin K is necessary for the synthesis of coagulation factors. Term infants, especially those who are exclusively breast fed, are deficient in vitamin K and consequently may have vitamin K deficiency bleeding (VKDB). Preterm infants are potentially at greater risk for VKDB because of delayed feeding and subsequent delay in the colonization of their gastrointestinal system with vitamin K producing microflora, as well as immature hepatic and hemostatic function. Read More

Medicine (Baltimore) 2017 Dec;96(51):e9368

Rationale: Spontaneous spinal epidural hematoma (SSEH) manifests from blood accumulating in the epidural space, compressing the spinal cord, and leading to acute neurological deficits. The disease's cloudy etiology and rarity contribute to dangerously suboptimal therapeutic principles. These neural deficits can be permanent, even fatal, if the SSEH is not treated in a timely and appropriate manner. Read More

Lab Med 2018 Jul;49(3):272-275

Division of Laboratory Medicine, Department of Pathology.

Rat poisoning should be considered in the differential diagnosis of a patient presenting with signs and symptoms of vitamin K deficiency without a more likely explanation. However, confirming this diagnosis may be difficult due to the varying sensitivities of available assays. A 40-year-old Caucasian woman presented to our hospital with chronic abdominal pain, hematuria, and a history of diarrhea of unknown etiology, despite an extensive work-up. Read More

Jpn Clin Med 2017 7;8:1179670717746333. Epub 2017 Dec 7.

Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.

Intraventricular hemorrhage (IVH) is a devastating morbidity in preterm infants and can result in poor neurodevelopmental outcomes. Intraventricular hemorrhage usually occurs within 72 hours after birth; post-acute-phase IVH (>1 week after birth) is uncommon. Development of the hemostatic system in fetuses and neonates is an age-dependent evolving process, and the neonatal hemostatic system is characterized by low levels of vitamin K-dependent factors, with further reduction caused by prematurity. Read More

Arch Argent Pediatr 2018 Feb;116(1):e19-e25

Allergology Outpatient Department, Provincial Hospital No 2, Rzeszow, Poland.

Introduction: Vitamin K deficiency is highly prevalent in cystic fibrosis (CF) patients despite supplementation. Moreover, no reliable risk factors for its occurrence are known. The aim was to assess the prevalence of vitamin K deficiency and associated factors in non-supplemented CF patients. Read More

Mediterr J Hematol Infect Dis 2018 1;10(1):e2018010. Epub 2018 Jan 1.

Paediatrics, Faculty of Medicine, Ain Shams University, Egypt.

Background: To evaluate the hazard of prolonged antibiotic therapy and/or persistent diarrhea on vitamin K1 (VK1) level and bleeding profile in infants (2-24 weeks).

Methods: A one-year case-control study, conducted at Ain Shams University, Egypt. 338 infants (2-24 weeks) were recruited and divided into 3 groups (1:1:3 ratios); group A (n=67) patients who received antibiotics for ≥10 days, group B (n=67) who had persistent diarrhea ≥ 14 days and group C (n=204) age- and gender- matched infants who had not either received antibiotics nor had diarrhea. Read More

Nutrients 2018 Jan 5;10(1). Epub 2018 Jan 5.

Institution of Clinical Science Lund, Medical Faculty, Lund University, S-22185 Lund, Sweden.

Background: Matrix Gla protein (MGP) is an extrahepatic protein that is dependent on glutamate carboxylation, a vitamin K-dependent process. Its dysfunctional form, desphospho-uncarboxylated-MGP, has been associated with increased arterial calcification and stiffness. The aim of this study was to measure the degree of postoperative carboxylation of MGP and two other Gla proteins in patients scheduled for abdominal or orthopaedic surgery. Read More