Serum Levels Of 25-hydroxycholecalciferol Research Articles

Vitamin D Receptor Gene Polymorphisms and Risk of Knee Osteoarthritis: Possible Correlations with TNF-α, Macrophage Migration Inhibitory Factor, and 25-Hydroxycholecalciferol Status.

Osteoarthritis (OA) etiology and pathogenesis not yet fully understood. We studied the role of vitamin D receptor single-nucleotide polymorphisms (VDR-SNPs), vitamin D3, serum and synovial macrophage migration inhibitory factor (MIF), and tumor necrosis factor-α (TNF-α) in the development and progression of knee OA (KOA). This study included 205 Egyptian subjects (105 patients with KOA and 100 unrelated, healthy matched subjects selected as controls). The patient group was divided into three groups according to KOA severity (mild, moderate, and severe), with 35 patients in each group. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique was used for the ApaI and TaqI SNPs. Vitamin D, serum and synovial TNF-α, and MIF assays were performed using ELISA kits. There were significantly lower serum levels of 25-hydroxycholecalciferol with significant increasing TNF-α and MIF levels in relation to disease severity among the cases (all: p˂0.05).Wild homozygous and heterozygous mutant genotypes (GG+GT) and G allele of ApaI demonstrated risk for KOA development, with odds ratio OR = 6.313 (95% confidence interval (CI) 2.074-19.210) and OR = 1.532 (95%CI 1.013-2.317), respectively. Homozygous mutant CC genotype and C allele of TaqI could be considered a risk factor associated with KOA development, with OR = 2.667 (95%CI 1.270-5.601) and OR = 0.737 (95%CI 0.496-1.095), respectively. VDR-SNPs, vitamin D3, TNF-α, and MIF could play an essential role in the pathogenesis and progression of KOA with mechanistic associations.

Role of antioxidant and oxidative stress levels in multiple sclerosis Iraqi patients

Multiple Sclerosis is a multifactorial disease characterized by demyelination and inflammation of the central nervous system. Accumulating data indicate that changes in the balance of antioxidants and oxidants contributed to the MS pathophysiology. The aim of the study to obtain a better understanding of the oxidative stress process to select a proper method of predicting the prognosis of the relapsing-remitting MS (RRMS). Serum of 97 patients (30 newly diagnosed RRMS patients and 67 RRMS patients underwent treatment) and 35 healthy individuals as control group. Serum levels of 25-hydroxycholecalciferol [25(OH)D3], vitamin E, vitamin C, malondialdehyde, protein carbonyl, and 8-hydroxydeoxyguanosine. There was a negative correlation between MDA and antioxidant (vitamin C and vitamin E), whereas a positive correlation between MDA and other oxidative stress (PC and 8-OHdG). Receiver operator characteristic analysis showed that PC was an ideal marker while vitamin C, MDA, 8-OHdG were excellent markers. Our data showed that the above markers as a mean could be used to predict MS disease and the extent of its progression.

Association of serum 25-Hydroxyvitamin D with Vitamin D intervention and outdoor activity among children in North China: an observational study

BackgroundLiving at high latitudes is one of the risk factors for vitamin D deficiency in children. However, evidence on vitamin D improvement for this pediatric population to date is limited. This study aims at evaluating the association of different vitamin D intervention methods and outdoor activity on the vitamin D status of children in North China.MethodsIn this observational study, a total of 55,925 children aged 1 month to 18 years old were recruited from pediatric outpatient departments from July 2016 to June 2017. Data on demographics, anthropometric measurements, vitamin D intervention (either prescribed by physicians or given by parents) and outdoor activity were recorded. The serum levels of 25-hydroxycholecalciferol (25(OH)D) were determined by high performance liquid chromatography tandem–mass spectrometry. Logistic regression analysis was performed to assess the association of vitamin D intervention or outdoor activity with blood vitamin D status, adjusted for age, gender, BMI for age, and seasons.ResultsThe overall rate of hypovitaminosis D was 65.60%. Of the children’s outdoor activity, 35.63, 31.95, and 32.42% were below 30 min/d, 30–60 min/d and over 60 min/d, respectively. Furthermore, the proportion of therapeutic intervention, supplementation intervention and no vitamin D intervention among the children was 16.48, 32.87, and 50.65%, respectively. After adjusted for confounding factors, vitamin D intervention was associated with a lower risk of hypovitaminosis D, with OR (95% CI) of 0.191 (0.180, 0.202) in children with therapeutic doses and 0.423 (0.404, 0.443) in those with supplementation doses, compared with children without vitamin D intervention. In addition, longer outdoor time was associated with a lower risk of hypovitaminosis D [0.479 (0.456, 0.504) for 60 min/d, 0.737 (0.701, 0.776) for 30–60 min/d], independent of vitamin D intervention.ConclusionsHigh prevalence of vitamin D deficiency was found in children living at high latitudes. Vitamin D intervention and outdoor activity are all negatively associated with children’s vitamin D deficiency. Routine vitamin D intervention combined with increased outdoor time might be an effective approach to prevent hypovitaminosis D among children, especially those at school, living at high latitudes.

The Prevalence of Vitamin D Deficiency and Its Related Factors Among Female Staff of Gonabad University of Medical Sciences, Gonabad City, Iran, in 2019

Background: Vitamin D (VitD) plays a significant role in human health, survival, and fertility. It is necessary for calcium absorption and bone growth and the regulation of the immune system. This study aims to determine the prevalence of VitD deficiency and the factors affecting it in women working in the campus of Gonabad University of Medical Sciences, Gonabad City, Iran. Methods: In this cross-sectional analytical study, 70 women working on the campus of Gonabad University of Medical Sciences in 2019 were selected by the census method. After obtaining their consent forms, the researcher-made checklist was completed by the participants. The serum levels of 25-hydroxycholecalciferol (25-OH D3) were the index for measuring VitD. The significance level is set below 0.05. Results: The Mean±SD level of VitD in the research units was 13.67±22.5 ng/mL. About 12.85% of the samples had severe deficiency (less than 10 ng/mL), 32.85% had moderate deficiency (10-20 ng/mL) and 31.42% had mild deficiency (20-30 ng/mL). The prevalence of VitD deficiency was lower in people with a history of physical activity, and those with a history of taking supplements. Also, the highest VitD deficiency was observed in the age group of older than 40 years. Conclusion: According to the results, the prevalence of VitD deficiency in the study population was high because 45.7% of the subjects had severe and moderate VitD deficiency.

Vitamin D(25-OH-cholecalciferol) in Cystic Fibrosis and the Relations with Cholesterol and Proteins

Study aimed to assess the level of 25-OH-cholecalciferol(vitamin D) and the relation with cholesterol, proteins and glycaemia levels in patients with cystic fibrosis. 58 patients underwent for the annual evaluations and were tested for vitamin D deficiency, as the centre�s protocol requires, besides dosage of cholesterol, glycaemia and proteins levels. Serum levels of 25-hydroxycholecalciferol were compared to levels of cholesterol, proteins and glycaemia, using Pearson correlation and logistic regression. The average value of 25-OH-cholecalciferol was 22,9 ng/mL, suggesting an important deficiency and different stages of 25-OH-cholecalciferol deficiency was found in the majority of patients. Nor a positive correlation neither negative relationship was found between vitamin D and cholesterol (r=0,23), glycaemia or proteins level. Vitamin D levels are not related to cholesterol or proteins in our study. Although cystic fibrosis is characterised by liposoluble vitamins deficiency and lipids impaired digestion, other factors influence the seric levels of vitamin D and lipids.

Randomized controlled trial of vitamin D supplementation in children with autism spectrum disorder.

Autism spectrum disorder (ASD) is a frequent developmental disorder characterized by pervasive deficits in social interaction, impairment in verbal and nonverbal communication, and stereotyped patterns of interests and activities. It has been previously reported that there is vitamin D deficiency in autistic children; however, there is a lack of randomized controlled trials of vitamin D supplementation in ASD children. This study is a double-blinded, randomized clinical trial (RCT) that was conducted on 109 children with ASD (85 boys and 24 girls; aged 3-10years). The aim of this study was to assess the effects of vitamin D supplementation on the core symptoms of autism in children. ASD patients were randomized to receive vitamin D3 or placebo for 4months. The serum levels of 25-hydroxycholecalciferol (25 (OH)D) were measured at the beginning and at the end of the study. The autism severity and social maturity of the children were assessed by the Childhood Autism Rating Scale (CARS), Aberrant Behavior Checklist (ABC), Social Responsiveness Scale (SRS), and the Autism Treatment Evaluation Checklist (ATEC). UMIN-CTR Study Design: trial number: UMIN000020281. Supplementation of vitamin D was well tolerated by the ASD children. The daily doses used in the therapy group was 300IU vitamin D3/kg/day, not to exceed 5,000IU/day. The autism symptoms of the children improved significantly, following 4-month vitamin D3 supplementation, but not in the placebo group. This study demonstrates the efficacy and tolerability of high doses of vitamin D3 in children with ASD. This study is the first double-blinded RCT proving the efficacy of vitamin D3 in ASD patients. Depending on the parameters measured in the study, oral vitamin D supplementation may safely improve signs and symptoms of ASD and could be recommended for children with ASD. At this stage, this study is a single RCT with a small number of patients, and a great deal of additional wide-scale studies are needed to critically validate the efficacy of vitamin D in ASD.

Adverse Effects of Vitamin D Deficiency on Outcomes of Patients With Chronic Hepatitis B

Vitamin D is an immunomodulator that might be involved in the pathogenesis of viral hepatitis. We investigated the effects of vitamin D deficiency on long-term outcomes of patients with chronic hepatitis B (CHB). We performed a prospective cohort study of 426 patients with CHB (65% male; mean age, 41 ± 13 years), who were enrolled from 1997 through 2000. Serum levels of 25-hydroxycholecalciferol (25(OH)D3) were measured on study enrollment (baseline). Patients were followed for 159 ± 46 months until last clinic visit or death; approximately 33% received antiviral therapy during the follow-up period. The primary outcome was a clinical event (hepatocellular carcinoma, complications of cirrhosis, or death). At baseline, the patients' mean serum level of hepatitis B virus DNA was 5.0 ± 2.1 log10 IU/mL; their mean level of 25(OH)D3 was 24.3 ± 9.4 ng/mL, and 348 patients (82%) had vitamin D deficiency (<32 ng/mL). Serum levels of 25(OH)D3 did not correlate with cirrhosis or viral load. Ninety-seven patients (22.8%) developed clinical events by a mean time of 118 ± 60 months after study enrollment. Patients who developed clinical events had lower baseline serum levels of 25(OH)D3 (23.2 ± 10.4 ng/mL) than patients who did not (28.2 ± 9.3 ng/mL, P < .001). Low baseline serum 25(OH)D3 was an independent factor associated with clinical events after adjustment for sex, age, and cirrhosis. The adjusted hazard ratio of vitamin D deficiency for clinical events was 1.90 (95% confidence interval [CI], 1.06-2.43; P = .04). The 15-year cumulative incidence rate of clinical events among patients with vitamin D deficiency was 25.5% (95% CI, 23.1%-27.9%), compared with 11.1% (95% CI, 7.4%-14.8%) in patients with normal serum levels of 25(OH)D3. Vitamin D deficiency is common among patients with CHB and is associated with adverse clinical outcomes.

Endocrine and Clinical Correlates of Myostatin Serum Concentration in Men—the STRAMBO Study

Myostatin is expressed mainly in skeletal muscle cells and acts as an inhibitor of muscle growth and differentiation. However, data on the determinants of serum myostatin concentrations in humans are limited. The aim of the study was to assess the correlates of serum myostatin concentrations in men. We conducted a cross-sectional analysis of the STRAMBO cohort. Men holding private health insurance coverage with Mutuelle de Travailleurs de la Région Lyonnaise were included in the study. A total of 1121 male volunteers aged 20-87 yr participated in the study. Nonfasting blood samples were collected. We measured the association of the investigated variables with circulating myostatin levels. Serum myostatin levels increased slightly with age until 57 yr and then decreased. Circulating myostatin levels showed circannual variation, with the highest concentration in spring. In men older than 57 yr, serum myostatin levels decreased across increasing quartiles of body mass index and of total central and peripheral fat mass (P<0.05 to <0.001). Serum myostatin levels were positively correlated with serum levels of 25-hydroxycholecalciferol (25OHD), even after adjustment for season. Average myostatin levels were 0.47 sd higher in men with 25OHD above 40 ng/ml, compared with those with 25OHD below 20 ng/ml (P<0.05). Current smokers had lower myostatin concentration. Neither current physical activity nor serum levels of PTH, testosterone, and 17β-estradiol were associated with myostatin concentrations. In men, circulating myostatin levels show seasonal changes and are associated with age, body mass index, fat mass, smoking, and 25OHD levels.

Increased vitamin D‐driven signalling and expression of the vitamin D receptor, MSX2, and RANKL in tooth resorption in cats

Tooth resorption occurs in 20-75% of cats (Felis catus). The aetiology is not known, but vitamin D is suggested to be involved. Vitamin D acts through a nuclear receptor (VDR) and increases the expression of receptor activator of nuclear factor-kappaB ligand (rankl) and muscle segment homeobox 2 (msx2) genes. Mice lacking the muscle segment homeobox 2 (msx2) gene show decreased levels of rankl, suggesting an interaction among VDR, MSX2, and RANKL. Here, we investigated the expression of VDR, MSX2, and RANKL proteins, and the activity of the VDR-mediated signalling pathway (using the quantitative polymerase chain reaction on VDR target genes), in tooth resorption, and measured the serum levels of vitamin D metabolites in cats. Tooth resorption was categorized into either resorptive or reparative stages. In the resorptive stage, odontoclasts expressed MSX2 and RANKL (100% and 88%, respectively) and fibroblasts expressed VDR and MSX2 (both at 100%), whereas fibroblasts expressed RANKL in only 29% of the sites analysed. In the reparative stage, cementoblasts expressed VDR, MSX2, and RANKL, whereas fibroblasts expressed VDR and MSX2, but not RANKL. The vitamin D status did not differ between the groups, based on the serum levels of 25-hydroxycholecalciferol. However, increased expression of VDR protein, and the relative gene expression levels of 1alpha-hydroxylase and the VDR-target gene, 24-hydroxylase, indicated the involvement of an active vitamin D signalling in the pathophysiology of tooth resorption in cats.

Serum Levels of 25-Hydroxycholecalciferol and 1,25-Dihydroxycholecalciferol in Dogs with Hypercalcaemia

1,25-Dihydroxycholecalciferol (1,25-(OH)2-D3) and 25-hydroxycholecalciferol (25-OH-D3) were measured among dogs with hypercalcaemia (total serum calcium > 3.01 mmol/L) due to various causes. All values were compared to those of healthy control dogs. Serum 1,25-(OH)]2-D3 was measured by a radioimmunoassay test and serum 25-OH-D3 was measured by a protein binding assay. 1,25-(OH)2-D3 ranged from 26 to 332 pmol/L (median 110.0) in dogs with lymphoma (n = 12); from 61 to 398 pmol/L (median 248.0) in dogs with primary hyperparathyreoidism (n = 5); from 28 to 310 pmol/L (median 88.5) in dogs with chronic renal failure (n = 10); and from 60 to 239 pmol/L (median 157.5) in control dogs (n = 24). There was no significant difference in 1,25-(OH)2-D3 among dogs with different causes of hypercalcaemia. 25-OH-D3 ranged from 64 to 291 nmol/L (median 101.5) in dogs with lymphoma; from 66 to 298 nmol/L (median 91.0) in dogs with primary hyperparathyreoidism; from 35 to 184 nmol/L (median 67.0) in dogs with chronic renal failure; and from 48 to 350 nmol/L (median 306.5) in control dogs. 25-OH-D3 was significantly lower in dogs with lymphoma, primary hyperparathyroidism and chronic renal failure than in control dogs. 1,25-(OH)2-D3 and 25-OH-D3 are not predictable in dogs with hypercalcaemia.

Age-related (type II) femoral neck osteoporosis in men: biochemical evidence for both hypovitaminosis D- and androgen deficiency-induced bone resorption.

The problem of osteoporosis in men has recently been recognized as an important public health issue. To test the hypothesis that endocrine deficiency-mediated alterations in bone metabolism might contribute to osteoporotic fracture risk in elderly men, serum levels of 25-hydroxycholecalciferol (25(OH)D), 1,25-dihydroxycholecalciferol (1,25(OH)2D), intact parathyroid hormone (PTH), testosterone, and estradiol were measured in 40 males (mean age 73 years) who were consecutively recruited within 18 h following a fracture of the proximal femur, and in an equal number of community-living older men (mean age 72 years) who served as controls. In addition, circulating osteocalcin and urinary excretion of (deoxy)pyridinoline were determined as markers of bone formation and resorption, respectively. No differences were observed between the mean serum concentrations of osteocalcin and estradiol. Serum levels of 25(OH)D, 1,25(OH)2D, and testosterone, however, were decreased in hip fracture patients. When correcting for differences in vitamin D binding protein, differences in 1,25(OH)2D did not persist, whereas serum 25(OH)D was still significantly lower in patients than in controls (6.1 +/- 4.3 vs. 7.6 +/- 2.8, p = 0.01). Similarly, a highly significant deficit was observed in the free testosterone index, calculated from total testosterone and the level of sex hormone binding globulin (2.6 +/- 1.3 vs. 8.2 +/- 2.9, p < 0.001). Serum PTH and urinary pyridinium cross-links, however, were markedly increased in the fracture group. Moreover, in fracture patients, free 25(OH)D and free testosterone were both significant and mutually independent negative predictors of (deoxy)pyridinoline excretion. Although limited by its cross-sectional design, the present study suggests that both hypovitaminosis D and androgen deficiency may predispose to bone resorption in elderly men and in turn to remodeling imbalance and fracture risk.

Serum 25-hydroxycholecalciferol concentration in newly detected hypertension

Although blood concentrations of the active metabolite 1,25-dihydroxyvitamin D are raised in hypertension, concentrations of 25-hydroxyvitamin D, the main vitamin D metabolite, do not appear to have been reported in newly detected hypertension. Serum levels of 25-hydroxycholecalciferol were measured in 186 newly detected hypertensive patients (blood pressure > 160/95 mm Hg and never on antihypertensive medication) and normotensive controls individually matched by sex, age (+/- 2 years), ethnicity, and date of interview. Serum 25-hydroxycholecalciferol levels were similar in cases (mean (SD) = 64 (21) nmol/L) and controls (67 (28) nmol/L, P = .20). We conclude that serum 25-hydroxycholecalciferol, a marker of body vitamin D, is normal in hypertension.

True fractional calcium absorption in Chinese children measured with stable isotopes (42Ca and44Ca)

True fractional Ca absorption (TFCA) was compared in children with different habitual Ca intakes using a double-label stable-isotope technique. Chinese children aged 7 years from Hongkong (n22) and Jiangmen (n12) participated in the study. An oral administration of 8 mg 44Ca in 100 g chocolate milk was given shortly after an intravenous injection of 0.75 mg 42Ca. Ca isotopic ratios were determined in urine samples collected 24 h later using thermal-ionization mass spectrometry. There was no significant difference in TFCA between Jiangmen and Hongkong children (P = 0.16). TFCA of a lower-Ca-intake group (Ca < or = 500 mg/d, n19) with mean Ca intake 359 mg/d was 63.1 (SD 10.7)% and that of a higher-Ca-intake group (Ca > 500 mg/d, n15) with mean Ca intake 862 mg/d was 54.8 (SD 7.3)%; the difference in TFCA was significant (P = 0.016). Serum levels of 25-hydroxycholecalciferol of the children were adequate (33.7 (SD 7.7) ng/ml). The present study indicates that growing children accustomed to a low-Ca diet appear to be able to enhance their absorptive capacity. If it is assumed that dietary Ca absorption by Chinese children resembles their TFCA from a single meal of chocolate milk, then the recommended dietary allowance (RDA) for Ca for Chinese children would be lower than the US RDA (800 mg/d), which is based on an estimated 40% Ca absorption as reported for Caucasian children. A comparative absorption study is necessary to determine whether there is any difference in TFCA between Caucasian and Chinese children.

Serum concentrations of vitamin D metabolites in different degrees of impaired renal function. Estimation of renal and extrarenal secretion rate of 24,25-dihydroxyvitamin D.

The serum levels of 25-hydroxycholecalciferol, 24,25-dihydroxycholecalciferol, and 1,25-dihydroxycholecalciferol were measured simultaneously in three groups of adults with different renal function: normal (n = 24), glomerular filtration rate (GFR) greater than 70 ml/min; moderately decreased (n = 15), GFR 5-35 ml/min, and severely decreased (n = 27), GFR less than 5 ml/min. 25-hydroxycholecalciferol was normal in both patient groups with decreased renal function. 1,25-dihydroxycholecalciferol was halved in the group with moderately decreased renal function (p less than 0.01) and severely decreased (almost undetectable) in the group with severely decreased renal function (p less than 0.01). In contrast, 24,25-dihydroxycholecalciferol was normal in the group with moderately decreased renal function and only halved (p less than 0.05) in the group with severely decreased renal function. These findings suggest extrarenal C-24 hydroxylase activity which may be stimulated by decreasing renal function, thus decreasing renal C-24 hydroxylase activity.

Circannual versus seasonal variations of longitudinally sampled 25-hydroxycholecalciferol serum levels

Seasonal variations in human serum levels of 25-hydroxycholecalciferol (25OHD) have been largely documented in transverse studies of population. But seasonality is not per se a demonstration that 25OHD serum levels fluctuate along the course of year according to a waveform profile with a periodic rhythm. Because of this, we attempted to investigate the possible occurrence of a circannual rhythm for 25OHD serum levels in a longitudinal design, by fitting a 365.25-day cosine curve to temporal biodata recorded in 10 clinically healthy subjects, monthly sampled for RIA determinations of 25OHD. Cosinor procedure statistically validated the occurrence of a circannual rhythm for 25OHD serum concentrations at a highly significant level of probability ( P = 0.0015) for null hypothesis amplitude = 0. With 95% of probability, amplitude ranges from 5.0 to 16.5 ng/ml (mean value of oscillation = 10 ng/ml), while acrophase is temporally located from September 14 to December 3 (mean timing = October 21). Yearly, mean values for 25OHD serum concentrations is of 40.3 ± 5.4 ng/ml as quantified by the line which transversely divides the cosine curve interpolating original biodata. By calculating the band of a complete 12 months variability which includes 90% of the distribution with 90% confidence limits, the circannual chronodesm of 25OHD serum levels has been obtained. Such a chronodesmic sinusoid has been compared to the circannual chronogram. By this comparison, a dissociation between the crest (October) and the peak (August) has been detected. The finding suggests that seasonal variations are superimposed to the circannual rhythm. Seasonal but also circannual changes, thus, characterize the yearly variability of 25OHD serum levels in man.

Serum 1,25-dihydroxycholecalciferol in anephric, haemodialyzed and kidney-transplanted patients. Effect of vitamin D3 supplement.

The serum levels of 25-hydroxycholecalciferol (25-OHD3) and 1,25-dihydroxycholecalciferol[1,25-(OH)2D3] were measured simultaneously in nephrectomized patients on maintenance haemodialysis, in haemodialyzed patients with preserved kidneys who were receiving different vitamin D supplement, and in patients who had undergone renal transplantation. The results indicate that the production of 1,25-(OH)2D3 can be stimulated in patients with minimal residual renal excretory function by increasing the serum levels of 25-OHD3. Successful renal transplantation was followed by a rise in serum 1,25-(OH)2D3 concentrations.

The Effects of Anticonvulsants on Liver and Bone Metabolism

Seven children who were suffered from rickets during administration of anti-convulsants were studied. In this study, the effects of anticonvulsants on liver and bone metabolism were discussed. The serum levels of 25-hydroxycholecalciferol were measured in all cases, and in three cases, serum parathyroid hormone le-vels were also measured.In six of seven patients, the serum levels of 25-hydroxycholecalciferol were subnormal or markedly low. And the serum levels of parathyroid hormone were markedly elevated in two of three patients.In all seven cases, serum alkaline phosphatase levels were markedly elevated. And in three of these patients, serum γ-glutamyl transpeptidase levels were also elevated without the increase of serum GPT or GOT.Though serum calcium levels were not always decreased, serum inorganic phosphorus levels were markedly low in all seven cases.All these patients were administered phenobarbital and acetazolamide. In six of them, metabolic acidosis was observed, and after elimination of acetazolamide, metabolic acidosis was corrected in five patients. And in two of them, the improvement of rachitic change occurred only after elimination of acetazolamide. These findings suggest the important role of acetazolamide in the development of rickets.Since the anticonvulsants such as phenobarbital and diphenylhydantoin accelerate the inactivation of vitamin D activity, the administration of these anticonvulsants seems to increase the requirement of vitamin D.

Skeletal metabolism and body composition in Cushing's syndrome.

ABSTRACT The techniques of total body neutron activation analysis and whole body counting were utilized to examine the effect of hypercortisolism on skeletal mass and body composition. Eight patients with Cushing's syndrome were studied. In addition, serum concentration of 25-hydroxycholecalciferol was measured in 4 of these patients, and in an additional 17 patients who were receiving exogenous glucocorticoids. Prior to therapy, skeletal mass (total body Ca) and lean body mass (40K) were considered to be decreased in 5 out of 7 patients. The osteopenia was generally not corrected in follow-up activations subsequent to treatment of the Cushing's syndrome. The only significant increases in total body calcium occurred in 2 patients who presumably had not completed body growth. Serum levels of 25-hydroxycholecalciferol were in the normal range in the spontaneous Cushing's, as well as the iatrogenic Cushing's syndrome patients. Thus, if glucocorticoids affect vitamin D metabolism, it must be at a step beyond ...