title: Exogenous and endogenous determinants of vitamin K status in cystic fibrosis.
abstract: Cystic fibrosis (CF) patients are at high risk for vitamin K deficiency. The effects of vitamin K supplementation are very ambiguous. Therefore, we aimed to define the determinants of vitamin K deficiency in a large cohort of supplemented - 146 (86.9%) and non-supplemented - 22 (13.1%) CF patients. Vitamin K status was assessed using prothrombin inducted by vitamin K absence (PIVKA-II) and undercarboxylated osteocalcin (u-OC). The pathological PIVKA-II concentration (≥ 2 ng/ml) and abnormal percentage of osteocalcin (≥ 20%) were found in 72 (42.8%) and 60 (35.7%) subjects, respectively. We found that liver involvement, diabetes, and glucocorticoid therapy were potential risk factors for vitamin K deficiency. Pathological concentrations of PIVKA-II occurred more frequently in patients with pancreatic insufficiency and those who have two severe mutations in both alleles of the CFTR gene. Pathological percentage of u-OC was found more frequently in adult CF patients and those not receiving vitamin K. However, it seems that there are no good predictive factors of vitamin K deficiency in CF patients in everyday clinical care. Early vitamin K supplementation in CF patients seems to be warranted. It is impossible to clearly determine the supplementation dose. Therefore, constant monitoring of vitamin K status seems to be justified.
authors.affiliation: Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Patrycja
authors.initials: P
authors.lastname: Krzyżanowska
authors.affiliation: Department of Pneumology and Cystic Fibrosis, Institute of Tuberculosis and Lung Diseases, Rabka, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Pogorzelski
authors.affiliation: National Tuberculosis and Lung Diseases Research Institute, Warsaw, Poland.
authors.forename: Wojciech
authors.initials: W
authors.lastname: Skorupa
authors.affiliation: Department of Informatics and Statistics, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Jerzy
authors.initials: J
authors.lastname: Moczko
authors.affiliation: Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Philip
authors.initials: P
authors.lastname: Grebowiec
authors.affiliation: Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Jarosław
authors.initials: J
authors.lastname: Walkowiak
mesh_terms: D000293:Adolescent; D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D015415:Biomarkers / Q000032:analysis; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003550:Cystic Fibrosis / Q000188:drug therapy / Q000473:pathology*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics; D019587:Dietary Supplements; D005260:Female; D005838:Genotype; D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D007118:Immunoassay; D007223:Infant; D019934:International Normalized Ratio; D008297:Male; D009752:Nutritional Status; D015675:Osteocalcin / Q000032:analysis / Q000737:chemistry; D020641:Polymorphism, Single Nucleotide; D011498:Protein Precursors / Q000032:analysis; D011516:Prothrombin / Q000032:analysis; D011552:Pseudomonas Infections / Q000188:drug therapy; D012044:Regression Analysis; D012307:Risk Factors; D014812:Vitamin K / Q000032:analysis*; D014813:Vitamin K Deficiency / Q000209:etiology; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D015415:Biomarkers; C505032:CFTR protein, human; D005938:Glucocorticoids; D011498:Protein Precursors; D015675:Osteocalcin; D014812:Vitamin K; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; C008208:acarboxyprothrombin; D011516:Prothrombin