title: Vitamin D status in primary hyperparathyroidism: effect of genetic background.
abstract: Primary hyperparathyroidism (PHPT) is associated with hypovitaminosis D as assessed by serum total 25-hydroxyvitamin D (TotalD) levels. The aim of this study is to evaluate whether this is also the case for the calculated bioavailable 25-hydroxyvitamin D (BioD) or free 25-hydroxyvitamin D (FreeD), and whether the vitamin D status is influenced by genetic background. We compared vitamin D status of 88 PHPT patients each with a matched healthy family member sharing genetic background, i.e., first-degree relative (FDR), or not, namely an in-law relative (ILR). We compared TotalD and vitamin D-binding protein (DBP), using the latter to calculate BioD and FreeD. We also genotyped two common DBP polymorphisms (rs7041 and rs4588) likely to affect the affinity for and levels of vitamin D metabolites. TotalD was lower (p < 0.001) in PHPT (12.3 ± 6.6 ng/mL) than either family member group (FDR: 19.4 ± 12.1 and ILR: 23.2 ± 14.1), whether adjusted for DBP or not. DBP levels were also significantly lower (p < 0.001) in PHPT (323 ± 73 mg/L) versus FDR (377 ± 98) or ILR (382 ± 101). The differences between PHPT and control groups for TotalD, BioD, and FreeD were maintained after adjustment for season, gender, and serum creatinine. 25-hydroxyvitamin D, evaluated as total, free, or bioavailable fractions, is decreased in PHPT. No difference was seen between first-degree relative and in-law controls, suggesting that neither genetic nor non-genetic background greatly influences the genesis of the hypovitaminosis D seen in PHPT.
authors.affiliation: Unit of Endocrinology, Medical Genetics, Internal Medicine, Clinical Pathology, Radiotherapy, Nuclear Medicine, Biostatistics, IRCCS "Casa Sollievo della Sofferenza", 71013, San Giovanni Rotondo, Foggia, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Battista
authors.affiliation: Unit of Endocrinology, Medical Genetics, Internal Medicine, Clinical Pathology, Radiotherapy, Nuclear Medicine, Biostatistics, IRCCS "Casa Sollievo della Sofferenza", 71013, San Giovanni Rotondo, Foggia, Italy.
authors.forename: Vito
authors.initials: V
authors.lastname: Guarnieri
authors.affiliation: Unit of Endocrinology, Medical Genetics, Internal Medicine, Clinical Pathology, Radiotherapy, Nuclear Medicine, Biostatistics, IRCCS "Casa Sollievo della Sofferenza", 71013, San Giovanni Rotondo, Foggia, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Carnevale
authors.affiliation: Unit of Endocrinology, Medical Genetics, Internal Medicine, Clinical Pathology, Radiotherapy, Nuclear Medicine, Biostatistics, IRCCS "Casa Sollievo della Sofferenza", 71013, San Giovanni Rotondo, Foggia, Italy.
authors.forename: Filomena
authors.initials: F
authors.lastname: Baorda
authors.affiliation: Unit of Endocrinology, Medical Genetics, Internal Medicine, Clinical Pathology, Radiotherapy, Nuclear Medicine, Biostatistics, IRCCS "Casa Sollievo della Sofferenza", 71013, San Giovanni Rotondo, Foggia, Italy.
authors.forename: Mauro
authors.initials: M
authors.lastname: Pileri
authors.affiliation: Unit of Endocrinology, Medical Genetics, Internal Medicine, Clinical Pathology, Radiotherapy, Nuclear Medicine, Biostatistics, IRCCS "Casa Sollievo della Sofferenza", 71013, San Giovanni Rotondo, Foggia, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Garrubba
authors.affiliation: Unit of Endocrinology, Medical Genetics, Internal Medicine, Clinical Pathology, Radiotherapy, Nuclear Medicine, Biostatistics, IRCCS "Casa Sollievo della Sofferenza", 71013, San Giovanni Rotondo, Foggia, Italy.
authors.forename: Antonio S
authors.initials: AS
authors.lastname: Salcuni
authors.affiliation: Unit of Endocrinology and Metabolic Diseases, Fondazione IRCCS Cà Granda, Department of Clinical Sciences and Community Health, University of Milan, 20122, Milan, Italy.
authors.forename: Iacopo
authors.initials: I
authors.lastname: Chiodini
authors.affiliation: Department of Internal Medicine and Medical Discipline, "Sapienza" Rome University, 00185, Rome, Italy.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Minisola
authors.affiliation: Department of Experimental Medicine, "Sapienza" Rome University, 00185, Rome, Italy.
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Romagnoli
authors.affiliation: Unit of Endocrinology and Metabolic Diseases, Fondazione IRCCS Cà Granda, Department of Clinical Sciences and Community Health, University of Milan, 20122, Milan, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Eller-Vainicher
authors.affiliation: Unit of Endocrinology, Medical Genetics, Internal Medicine, Clinical Pathology, Radiotherapy, Nuclear Medicine, Biostatistics, IRCCS "Casa Sollievo della Sofferenza", 71013, San Giovanni Rotondo, Foggia, Italy.
authors.forename: Stefano A
authors.initials: SA
authors.lastname: Santini
authors.affiliation: Unit of Endocrinology, Medical Genetics, Internal Medicine, Clinical Pathology, Radiotherapy, Nuclear Medicine, Biostatistics, IRCCS "Casa Sollievo della Sofferenza", 71013, San Giovanni Rotondo, Foggia, Italy.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Parisi
authors.affiliation: Unit of Endocrinology, Medical Genetics, Internal Medicine, Clinical Pathology, Radiotherapy, Nuclear Medicine, Biostatistics, IRCCS "Casa Sollievo della Sofferenza", 71013, San Giovanni Rotondo, Foggia, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Frusciante
authors.affiliation: Unit of Endocrinology, Medical Genetics, Internal Medicine, Clinical Pathology, Radiotherapy, Nuclear Medicine, Biostatistics, IRCCS "Casa Sollievo della Sofferenza", 71013, San Giovanni Rotondo, Foggia, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Fontana
authors.affiliation: Unit of Endocrinology, Medical Genetics, Internal Medicine, Clinical Pathology, Radiotherapy, Nuclear Medicine, Biostatistics, IRCCS "Casa Sollievo della Sofferenza", 71013, San Giovanni Rotondo, Foggia, Italy.
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Copetti
authors.affiliation: Experimental Therapeutics and Metabolism, McGill University Health Centre-Research Institute, and Departments of Medicine, Physiology and Human Genetics, McGill University, Montreal, QC, H4A 3J1, Canada.
authors.forename: Geoffrey N
authors.initials: GN
authors.lastname: Hendy
authors.affiliation: Unit of Endocrinology, Medical Genetics, Internal Medicine, Clinical Pathology, Radiotherapy, Nuclear Medicine, Biostatistics, IRCCS "Casa Sollievo della Sofferenza", 71013, San Giovanni Rotondo, Foggia, Italy. alscill@tin.it.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Scillitani
authors.affiliation: Departments of Laboratory Medicine and Pathobiology, Medicine and Genetics, University of Toronto, Toronto, ON, M4N 3M5, Canada.
authors.forename: David E C
authors.initials: DE
authors.lastname: Cole
mesh_terms: D000328:Adult; D000368:Aged; D005190:Family; D005260:Female; D006801:Humans; D049950:Hyperparathyroidism, Primary / Q000097:blood / Q000150:complications / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D012621:Seasons; D012737:Sex Factors; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications / Q000235:genetics*; D014809:Vitamin D-Binding Protein / Q000235:genetics*
chemical_list: D014809:Vitamin D-Binding Protein; D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: Bioavailable 25-hydroxyvitamin D; Free 25-hydroxyvitamin D; Primary hyperparathyroidism; Vitamin D-binding protein