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Neuromuscul Disord 2021 May 11. Epub 2021 May 11.

Division of Critical Care Medicine, The Children's Hospital of Philadelphia, 3401 Civic Center Blvd, Philadelphia, PA, United States; Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, United States; Department of Anesthesiology and Critical Care Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, United States. Electronic address:

X-linked myotubular myopathy (XLMTM) is a rare congenital myopathy characterized by profound hypotonia and poor respiratory effort at birth. The condition is associated with multiple morbidities including chronic respiratory insufficiency, feeding tube dependence, and rarely, vitamin K deficiency leading to bleeding and coagulopathy. We report a case of a 6-month-old boy with X-linked myotubular myopathy who experienced a fatal intracranial hemorrhage due to vitamin K deficiency without prior clinical evidence of cholestasis or micronutrient deficiency. Read More

Am J Case Rep 2021 Jun 7;22:e930026. Epub 2021 Jun 7.

Department of Nephrology, Transplantology and Internal Medicine, Pomeranian Medical University, Szczecin, Poland.

BACKGROUND Calciphylaxis is a rare and lifethreatening syndrome characterized by small vascular calcifications, which lead to the occlusion of blood vessels and painful skin lesions with tissue necrosis. Although the disease can develop in a population without kidney failure, it is typically detected in patients receiving dialysis, with an increasing frequency ranging from 1% to 4%. Therefore, the disease is also known as calcific uremic arteriolopathy. Read More

Gastroenterology 2021 Jun 3. Epub 2021 Jun 3.

Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, the Netherlands.

J Pediatr Hematol Oncol 2021 May 31. Epub 2021 May 31.

Department of Ophthalmology, Division of Plastic and Reconstructive Surgery Department of Ophthalmology, Division of Pediatric and Strabismus Department of Child Health, Division of Pediatric Hematology-Oncology Department of Ophthalmology, Faculty of Medicine, University of Indonesia, Dr Cipto Mangunkusumo Hospital Department of Ophthalmology, Dr Cipto Mangunkusumo Hospital, Jakarta, Indonesia.

Spontaneous retrobulbar hemorrhage is a rare yet vision-threatening condition. We reported a 5-month-old male infant with sudden onset of left eye proptosis with no prior history of getting vitamin K injection after birth. Head computed tomography scan revealed retrobulbar and intracranial hemorrhages. Read More

Case Rep Womens Health 2021 Jul 20;31:e00329. Epub 2021 May 20.

Department of Obstetrics and Gynecology, Division of Maternal and Fetal Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, United States of America.

Introduction: Fetal intracranial hemorrhage (ICH) is a rare but serious prenatal diagnosis. Predisposing factors include maternal trauma and fetal coagulation dysfunction. Maternal vitamin K deficiency has been described as an etiology. Read More

Osteoarthritis Cartilage 2021 May 10. Epub 2021 May 10.

Molecular Epidemiology, Department of Biomedical Data Sciences, Leiden University Medical Center, Leiden, the Netherlands. Electronic address:

Objective: We here aimed to characterize changes of Matrix Gla Protein (MGP) expression in relation to its recently identified OA risk allele rs1800801-T in OA cartilage, subchondral bone and human ex vivo osteochondral explants subjected to OA related stimuli. Given that MGP function depends on vitamin K bioavailability, we studied the effect of frequently prescribed vitamin K antagonist warfarin.

Methods: Differential (allelic) mRNA expression of MGP was analyzed using RNA-sequencing data of human OA cartilage and subchondral bone. Read More

Exp Ther Med 2021 Jun 16;21(6):642. Epub 2021 Apr 16.

Department of Neurology, 'Iuliu Hatieganu' University of Medicine and Pharmacy Cluj-Napoca, Cluj-Napoca 400012, Romania.

Hyperemesis gravidarum (HG) refers to severe nausea and emesis noted during pregnancy. However, no consensus exists on the specific diagnostic criteria that can be used for this condition. The aim of the present systematic review was to summarize the available evidence regarding the severe complications observed during HG with a heightened risk of fatality. Read More

Eur J Clin Invest 2021 May 4:e13588. Epub 2021 May 4.

Department of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.

Deregulations in gut microbiota may play a role in vascular and bone disease in chronic kidney disease (CKD). As glomerular filtration rate declines, the colon becomes more important as a site of excretion of urea and uric acid, and an increased bacterial proteolytic fermentation alters the gut microbial balance. A diet with limited amounts of fibre, as well as certain medications (eg phosphate binders, iron supplementation, antibiotics) further contribute to changes in gut microbiota composition among CKD patients. Read More

Eur J Vasc Endovasc Surg 2021 May 1. Epub 2021 May 1.

Department of Cardiac, Thoracic and Vascular Surgery, Odense University Hospital, Odense, Denmark; Vascular Research Unit, Regional Hospital Central Denmark, Viborg, Denmark; Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.

Objective: Inactivation of matrix Gla protein (MGP), using vitamin K antagonists or vitamin K deficiency results in increased vascular calcification, which has been associated with increased risk of symptomatic or ruptured abdominal aortic aneurysm (AAA). Insufficient activation of MGP leads to increased levels of undercarboxylated forms of MGP, measured as a dephosphorylated, undercarboxylated MGP (dp-ucMGP) in plasma. This study aimed to investigate whether the level of inactivated MGP influenced the risk of having an AAA, the risk of AAA progression, and overall mortality. Read More

Curr Opin Nephrol Hypertens 2021 07;30(4):430-436

AGE Research Group, NIHR Newcastle Biomedical Research Centre, Newcastle University and Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK.

Purpose Of Review: Vascular calcification is a common and important cardiovascular risk factor in patients with chronic kidney disease (CKD). Recent advances in the understanding of the biology of vascular calcification implicate vitamin K-dependent proteins as important regulators in this process. This review highlights recent key advances in vascular biology, epidemiology, and clinical trials in this rapidly evolving field. Read More

BMC Cancer 2021 Apr 13;21(1):401. Epub 2021 Apr 13.

Department of Laboratory, Tianjin Medical University Cancer Institute and Hospital, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, National Clinical Research Center for Cancer, Huanhuxi Road, Hexi District, Tianjin, 300060, China.

Background: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors of the digestive system and has high morbidity and mortality rates. It is essential to search new biomarkers to improve the accuracy of early HCC diagnosis. Therefore, we evaluated the diagnostic value of prothrombin induced by vitamin K deficiency or antagonist- II (PIVKA-II) as a potential biomarker that complements α-fetoprotein (AFP) in HCC by detecting the serum PIVKA-II levels. Read More

Pediatr Emerg Care 2021 04;37(4):e218

Department of Paediatrics and Adolescent Medicine, The Hong Kong Children's Hospital Hong Kong

Am J Transplant 2021 Mar 19. Epub 2021 Mar 19.

Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, UK.

Premature cardiovascular disease and death with a functioning graft are leading causes of death and graft loss, respectively, in kidney transplant recipients (KTRs). Vascular stiffness and calcification are markers of cardiovascular disease that are prevalent in KTR and associated with subclinical vitamin K deficiency. We performed a single-center, phase II, parallel-group, randomized, double-blind, placebo-controlled trial (ISRCTN22012044) to test whether vitamin K supplementation reduced vascular stiffness (MRI-based aortic distensibility) or calcification (coronary artery calcium score on computed tomography) in KTR over 1 year of treatment. Read More

Gut Microbes 2021 Jan-Dec;13(1):1-16

Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA, USA.

Vitamins have well-established roles in bacterial metabolism. Menaquinones (MKn, n = prenyl units in sidechain) are bacterially produced forms of vitamin K produced by the gut microbiota and consumed in the diet. Little is known about the influence of dietary vitamin K quinones on gut microbial composition and MKn production. Read More

Eur Heart J Case Rep 2021 Jan 13;5(1):ytaa481. Epub 2020 Dec 13.

Department of Paediatric Cardiology, Kepler University Hospital GmbH, Krankenhausstrasse 26-30, 4020 Linz, Austria.

Background : Vitamin K deficiency bleeding is a life-threatening complication in early infancy. Exclusive breastfeeding and neonatal cholestasis syndromes, most notable α-1-antitrypsin deficiency, have been reported to be risk factors. Intracranial haemorrhage is most common. Read More

Kaohsiung J Med Sci 2021 Feb 26. Epub 2021 Feb 26.

Department of Biochemistry, Molecular medicine and Nutrigenomics, Faculty of Pharmacy, Medical University of Varna, Varna, Bulgaria.

The present cross-sectional clinical study aimed to examine the connection between statin exposure, coronary artery calcification (CAC), and vitamin K-dependent proteins (VKDPs) in patients with cardiovascular (CV) conditions. Two groups of patients were studied: patients with established CV disease (CVD) and healthy patients at moderate risk for CVD (a control group). The groups were also split into statin users and non-users. Read More

PLoS One 2021 24;16(2):e0247623. Epub 2021 Feb 24.

Division of Renal Medicine and Baxter Novum, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden.

Patients with chronic kidney disease (CKD) suffer from vitamin K deficiency and are at high risk of vascular calcification (VC) and premature death. We investigated the association of functional vitamin K deficiency with all-cause mortality and whether this association is modified by the presence of VC in CKD stage 5 (CKD G5). Plasma dephosphorylated-uncarboxylated matrix Gla-protein (dp-ucMGP), a circulating marker of functional vitamin K deficiency, and other laboratory and clinical data were determined in 493 CKD G5 patients. Read More

MedEdPORTAL 2021 01 25;17:11078. Epub 2021 Jan 25.

Assistant Professor, Clinical Pediatrics, Division of Emergency Medicine, University of Washington School of Medicine and Seattle Children's Hospital.

Introduction: The American Academy of Pediatrics recommends vitamin K prophylaxis at birth for all newborns to prevent vitamin K deficiency bleeding (VKDB). Despite a lack of evidence for serious harms, barriers to prophylaxis, including parental refusal, are rising, as are cases of VKDB.

Methods: This simulation involved an infant presenting to the emergency department who decompensated due to a cerebral hemorrhage caused by VKDB and was treated by pediatric and emergency providers. Read More

J Intensive Care 2021 Jan 18;9(1):11. Epub 2021 Jan 18.

Division of Anaesthesia and Intensive Care, Department of Clinical Sciences, Lund University, SE-22184, Lund, Sweden.

Background: Previous studies have indicated that vitamin K deficiency is common in non-bleeding critically ill patients with slightly prolonged prothrombin time-international normalized ratio (PT-INR). It has never been investigated thoroughly whether the administration of vitamin K to these patients could affect their PT-INR. Therefore, the aim of this registry study was to evaluate changes in PT-INR in response to vitamin K in critically ill patients with PT-INR in the range of 1. Read More

Int Urol Nephrol 2021 May 12;53(5):1015-1023. Epub 2021 Jan 12.

Internal Medicine Department, Faculty of Medicine, Minia University, Aswan-Cairo Agricultural Road, El-Minia, 61111, Egypt.

Background: Vascular calcification contributes to morbidity and mortality in patients with ESRD on maintenance hemodialysis.

Aims: To study the relationship between osteocalcin and vascular calcification.

Methods: 160 patients with ESRD on maintenance hemodialysis and 60 age-and sex-matched healthy controls were recruited. Read More

Calcif Tissue Int 2021 04 6;108(4):476-485. Epub 2021 Jan 6.

Laboratory Medicine Unit, Department of Medicine, University of Padua, Padua, Italy.

Vitamin K is principally known because it is involved in blood coagulation. Furthermore, epidemiological studies showed that its deficit was associated with increased fragility fractures, vascular calcification and mortality. There are two main types of vitamin K vitamers: Phylloquinone (or PK) and Menaquinones (MKn). Read More

Child Abuse Negl 2021 Feb 2;112:104901. Epub 2021 Jan 2.

Flaum Eye Institute and Golisano Children's Hospital, University of Rochester, New York, USA. Electronic address:

Background: Retinal hemorrhages (RH) are a common manifestation of abusive head trauma (AHT) resulting from acceleration-deceleration injury with or without blunt impact. Evaluation of a child with RH requires careful consideration of these differential diagnoses. The extent to which coagulopathy alone can cause RH would be useful to understand as coagulopathy may accompany AHT. Read More

Neonatal Netw 2020 Nov;39(6):356-362

Vitamin K is a fat-soluble vitamin essential for the formation of factors in the clotting cascade. Newborns are born with insufficient levels of vitamin K, resulting in high risk for vitamin K deficiency bleeding (VKDB). Vitamin K deficiency bleeding can occur in the first week of life ("classic" VKDB) and also between 2 weeks and 3 months of age ("late" VKDB). Read More

Cureus 2020 Nov 7;12(11):e11374. Epub 2020 Nov 7.

Hospital Medicine, Marshfield Medical Center, Marshfield, USA.

Nutritionally acquired vitamin K deficiency is a rare condition in adults and can uncommonly present as hemorrhagic pleural effusion. We discuss the case of A 44-year-old apparently healthy man who presented with left-sided pleuritic chest pain two months after experiencing upper respiratory tract symptoms. Imaging revealed a loculated left-sided effusion, and a corresponding thoracentesis yielded exudative hemorrhagic fluid with no microbial growth. Read More

Nutrients 2020 Nov 25;12(12). Epub 2020 Nov 25.

Department of Medicine, University Health Network, University of Toronto, 200 Elizabeth Street, Eaton North 7-221, Toronto, ON M5G 2C4, Canada.

Vitamin K acts as a coenzyme of carboxylase, catalyzing the carboxylation of several vitamin K dependent proteins. Beyond its well-known effects on blood coagulation, it also exerts relevant effects on bone and the vascular system. In this review, we point out the relevance of an adequate vitamin K intake to obtain sufficient levels of carboxylated (active form) vitamin K dependent proteins (such as Osteocalcin and matrix Gla protein) to prevent bone health. Read More

Med Hypotheses 2020 Nov 25;144:110218. Epub 2020 Aug 25.

Department of Internal Medicine, Canisius-Wilhelmina Hospital, Nijmegen, The Netherlands.

Covid-19, caused by SARS-CoV-2, has major world-wide health-related and socio-economic consequences. There are large disparities in the burden of Covid-19 with an apparent lower risk of poor outcomes in East Asians compared to populations in the West. A recent study suggested that Covid-19 leads to a severe extrahepatic vitamin K insufficiency, which could lead to impaired activation of extrahepatic proteins like endothelial anticoagulant protein S in the presence of normal hepatic procoagulant activity. Read More

Brain Dev 2021 Feb 31;43(2):200-207. Epub 2020 Oct 31.

Department of Pediatrics, Akitsu Ryoiku-en, Tokyo, Japan.

Objectives: We aimed to determine serum 25-hydroxyvitamin D (25(OH)D) and undercarboxylated osteocalcin (ucOC) levels in severe motor and intellectual disabilities (SMID) patients and their association with bone turnover biomarkers.

Methods: We assessed vitamin D and K levels as indicators of osteoporosis in institutionalized adults with SMID. From December 2019 to February 2020, 93 institutionalized patients (48 men, 45 women; median age, 49 years) underwent annual routine examinations. Read More

J Nutr 2020 12;150(12):3171-3179

Department of Epidemiology and Data Science, Amsterdam University Medical Center, Amsterdam, The Netherlands.

Background: A low vitamin D and K status has been associated with increased cardiovascular disease (CVD) risk but the evidence of their combined effect on cardiovascular health is limited.

Objectives: Our study aimed to investigate the prospective association of vitamin D and K status with subclinical measures of cardiovascular health and all-cause mortality among a population of Dutch Caucasians.

Methods: We performed an observational prospective study on 601 participants of the Hoorn Study (mean ± SD age: 70 ± 6 y, 50. Read More

Inform Med Unlocked 2020 12;21:100443. Epub 2020 Oct 12.

Division of Biomedical Sciences, School of Medicine, University of California Riverside, 900 University Ave, Riverside, CA, 92521, United States.

An urgent question of coronavirus disease 2019 (COVID-19) is population variation in susceptibility to SARS-CoV-2 infection and symptom severity. We explore the expression profiles of SARS-CoV-2 host genes, their population variations, associated genetic variants, age- and sex-dependency in normal individuals. SARS-CoV-2 host genes are provisionally defined as the human genes that are experimentally validated or bioinformatically predicted to interact with SARS-CoV-2 proteins. Read More

J Pediatr (Rio J) 2020 Oct 13. Epub 2020 Oct 13.

Department of Pediatrics, College of Medicine, University of Misan, Amarah, Iraq. Electronic address:

Objective: To study the presenting clinical and demographic features, risk factors, and outcome of infants with late vitamin K deficiency bleeding.

Methods: Over a 5-year study period, the presenting clinical features and outcome of all 47 infants observed aged less than 6 months, who were diagnosed with late-onset primary and secondary VKDB by detailed history, physical examination, and laboratory findings were evaluated. Confirmed primary late VKDB was diagnosed when no cause other than breastfeeding could be found, while in the secondary subtype additional risk factors compromising the vitamin K effect were diagnosed. Read More