title: Ionized calcium and 1,25-dihydroxyvitamin D concentration in serum of patients with sarcoidosis.
abstract: The aim of this study was to evaluate alterations in calcium metabolism in sarcoidosis. The serum concentrations of calcium (sCa), ionized calcium (sCa2+), 1,25-dihydroxyvitamin D (s1,25(OH)2D3) and parathyroid hormone (sPTH), serum angiotensin-converting enzyme activity (sACE) and urinary excretion of calcium (uCa) were studied in 36 Japanese patients with pulmonary sarcoidosis, aged 48.1+/-15.3 yrs (mean+/-SD), 15 males and 21 females. During the study the patients were on a daily diet with 500 mg calcium and 1000 mg phosphorus for a total of 6 days. sCa2+ was above the normal range (>1.26 mmol x L(-1)) in 10 patients (27.8%), 12 patients (33.3%) were hypercalciuric, and 16 patients (44.4%) showed alteration in calcium metabolism, with an increase in values of sCa, sCa2+ or uCa. There was a significant correlation between sCa2+ and s1,25(OH)2D3 (p<0.001), as well as between sCa2+ and sACE (p<0.001). s1,25(OH)2D3 in patients with extrathoracic involvement (ETI) tended to be higher than in patients without ETI. sCa2+ was less than 1.23 mmol x L(-1) (p<0.05) in the majority of patients without ETI, and sCa2+ was less than 1.24 mmol x L(-1) in the majority of normocalciuric patients. In conclusion, a disease-related alteration in calcium metabolism was seen in about 40% of patients with sarcoidosis, and 1,25-dihydroxyvitamin D probably plays a crucial role in this abnormality. The serum concentration of ionized calcium was considered to be a useful index for the disease activity of sarcoidosis.
authors.affiliation: Division of Pulmonary Medicine, Chest Disease Research Institute, Kyoto University, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Hamada
authors.forename: S
authors.initials: S
authors.lastname: Nagai
authors.forename: T
authors.initials: T
authors.lastname: Tsutsumi
authors.forename: T
authors.initials: T
authors.lastname: Izumi
mesh_terms: D000328:Adult; D002117:Calcitriol / Q000097:blood*; D002118:Calcium / Q000097:blood* / Q000652:urine; D005260:Female; D006801:Humans; D006934:Hypercalcemia / Q000097:blood; D007477:Ions; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D010281:Parathyroid Hormone / Q000097:blood; D007703:Peptidyl-Dipeptidase A / Q000097:blood; D012507:Sarcoidosis / Q000097:blood*
chemical_list: D007477:Ions; D010281:Parathyroid Hormone; D007703:Peptidyl-Dipeptidase A; D002117:Calcitriol; D002118:Calcium