In current clinical practice, a thorough understanding of vitamin D metabolism is in high demand both for patients with various diseases and for healthy individuals. Analytical techniques that ...provide simultaneous measurement of multiple metabolites are preferred. Herein, the development of an HPLC-DMS-MS/MS method for the quantitation of vitamin D compounds (25(OH)D
, 25(OH)D
, 1,25(OH)
D
, 3-epi-25(OH)D
, 24,25(OH)
D
, and D
) in serum is described. The selected sample preparation procedure based on the combination of liquid-liquid and solid-phase extraction, which excluded a lengthy derivatization step, was compared with other common approaches. Sensitivity was increased through the implementation of differential ion mobility separation. The proposed assay allowed us to determine the low abundant 1,25(OH)
D
with the detection limit of 10 pg/mL. The validation study showed good linearity (r
> 0.99), a wide analytical range (2.5-75 ng/mL for 25(OH)D
), and acceptable precision (<7%) for all metabolites. The recovery ranged from 71% to 93% and the matrix effect from 0.80 to 0.95 depending on the metabolite; accuracy determination was performed using DEQAS controls.
Despite being a classical growth disorder, pituitary gigantism has not been studied previously in a standardized way. We performed a retrospective, multicenter, international study to characterize a ...large series of pituitary gigantism patients. We included 208 patients (163 males; 78.4%) with growth hormone excess and a current/previous abnormal growth velocity for age or final height >2 s.d. above country normal means. The median onset of rapid growth was 13 years and occurred significantly earlier in females than in males; pituitary adenomas were diagnosed earlier in females than males (15.8 vs 21.5 years respectively). Adenomas were ≥10 mm (i.e., macroadenomas) in 84%, of which extrasellar extension occurred in 77% and invasion in 54%. GH/IGF1 control was achieved in 39% during long-term follow-up. Final height was greater in younger onset patients, with larger tumors and higher GH levels. Later disease control was associated with a greater difference from mid-parental height (r=0.23, P=0.02). AIP mutations occurred in 29%; microduplication at Xq26.3 – X-linked acrogigantism (X-LAG) – occurred in two familial isolated pituitary adenoma kindreds and in ten sporadic patients. Tumor size was not different in X-LAG, AIP mutated and genetically negative patient groups. AIP-mutated and X-LAG patients were significantly younger at onset and diagnosis, but disease control was worse in genetically negative cases. Pituitary gigantism patients are characterized by male predominance and large tumors that are difficult to control. Treatment delay increases final height and symptom burden. AIP mutations and X-LAG explain many cases, but no genetic etiology is seen in >50% of cases.
There is increasing data regarding the association between vitamin D and COVID-19. This study aimed to reveal the alterations of vitamin D metabolism in the setting of COVID-19. We examined 119 adult ...COVID-19 inpatients and 44 apparently healthy adult individuals with similar serum 25OH-D3 levels as a reference group. The assessment included serum biochemical parameters (total calcium, albumin, phosphorus, creatinine), parathyroid hormone (PTH), vitamin D-binding protein (DBP), vitamin D metabolites (25OH-D3, 25OH-D2, 1,25(OH)2D3, 3-epi-25OH-D3, 24,25(OH)2D3 and D3) and free 25OH-D. COVID-19 patients had in general very low vitamin D levels (median 25OH-D3 equals 10.8 ng/mL), accompanied by an increased production of the active vitamin D metabolite (1,25(OH)2D3), estimated as higher 1,25(OH)2D3 serum levels (61 44; 81 vs. 40 35; 50 pg/mL, p < 0.001) and lower 25OH-D3/1,25(OH)2D3 ratio (175 112; 260 vs. 272 200; 433, p < 0.001) which is presumably aimed at preventing hypocalcemia. Patients with COVID-19 also had elevated DBP (450 386; 515 vs. 392 311; 433 mg/L, p < 0.001) and low free 25OH-D levels (<LoB vs. 3.9 3.2; 4.4 pg/mL, p < 0.001). Follow-up assessment of the COVID-19 inpatients showed recovery of the observed changes. Overall, hospitalized patients with an acute course of COVID-19 have not only very low levels of 25OH-D but also profound abnormalities in the metabolism of vitamin D regardless of the clinical course of the disease. These alterations might exacerbate existing vitamin D deficiency and its negative impact.
In this study we aimed to assess vitamin D metabolism in patients with Cushing's disease (CD) compared to healthy individuals in the setting of bolus cholecalciferol treatment. The study group ...included 30 adults with active CD and the control group included 30 apparently healthy adults with similar age, sex and BMI. All participants received a single dose (150,000 IU) of cholecalciferol aqueous solution orally. Laboratory assessments including serum vitamin D metabolites (25(OH)D
, 25(OH)D
, 1,25(OH)
D
, 3-epi-25(OH)D
and 24,25(OH)
D
), free 25(OH)D, vitamin D-binding protein (DBP) and parathyroid hormone (PTH) as well as serum and urine biochemical parameters were performed before the intake and on Days 1, 3 and 7 after the administration. All data were analyzed with non-parametric statistics. Patients with CD had similar to healthy controls 25(OH)D
levels (
> 0.05) and higher 25(OH)D
/24,25(OH)
D
ratios (
< 0.05) throughout the study. They also had lower baseline free 25(OH)D levels (
< 0.05) despite similar DBP levels (
> 0.05) and lower albumin levels (
< 0.05); 24-h urinary free cortisol showed significant correlation with baseline 25(OH)D
/24,25(OH)
D
ratio (r = 0.36,
< 0.05). The increase in 25(OH)D
after cholecalciferol intake was similar in obese and non-obese states and lacked correlation with BMI (
> 0.05) among patients with CD, as opposed to the control group. Overall, patients with CD have a consistently higher 25(OH)D
/24,25(OH)
D
ratio, which is indicative of a decrease in 24-hydroxylase activity. This altered activity of the principal vitamin D catabolism might influence the effectiveness of cholecalciferol treatment. The observed difference in baseline free 25(OH)D levels is not entirely clear and requires further study.
Corticotropinomas and adrenocorticotropic hormone (ACTH)-secreting neuroendocrine tumors exhibit differential levels of some microRNAs (miRs) compared to normal tissue. Because miRs can be released ...from tissues into circulation, they offer promise as novel disease biomarkers.
To evaluate whether miRs are differentially detected in plasma samples of patients with ACTH-dependent Cushing's syndrome (CS).
Case-control study.
Morning fasting plasma samples were collected from 41 consecutive patients with confirmed ACTH-dependent CS and 11 healthy subjects and stored at -80°C. Twenty-one miRs previously reported to be differentially expressed in ACTH-secreting tumors vs. healthy tissue samples were quantified in plasma by qPCR.
Among enrolled subjects, 28 were confirmed to have Cushing's disease (CD), 13 had ectopic ACTH secretion (EAS) and 11 were healthy controls. We found statistically significant differences in the circulating levels of miR-16-5p 45.04 (95% CI 28.77-61.31) in CD vs. 5.26 (2.65-7.87) in EAS,
< 0.001;
= 0.001, miR-145-5p 0.097 (0.027-0.167) in CD vs. undetectable levels in EAS,
= 0.008;
= 0.087 and differences in miR-7g-5p 1.842 (1.283-2.400) in CD vs. 0.847 (0.187-1.507) in EAS,
= 0.02;
= 0.14. The area under the receiver-operator (ROC) curve was 0.879 (95% CI 0.770-0.987),
< 0.001, when using miR-16-5p to distinguish between CD and EAS. Circulating levels of miR-16-5p in the healthy control group differed from that of both the CD and EAS groups.
Plasma miR levels differ in patients with CD and EAS. In particular, miR-16-5p, miR-145-5p and miR-7g-5p are promising biomarkers for further research to differentiate ACTH-dependent CS.
In this prospective controlled study, we examined 25 adults with adequately controlled (HbA1c level < 8.0%) type 1 diabetes mellitus (T1DM) and 49 conditionally healthy adults, intending to reveal ...the diversity of vitamin D metabolism in the setting of cholecalciferol intake at a therapeutic dose. All patients received a single dose (150,000 IU) of cholecalciferol aqueous solution orally. Laboratory assessments including serum vitamin D metabolites (25(OH)D
, 25(OH)D
, 1,25(OH)
D
, 3-epi-25(OH)D
and 24,25(OH)
D
), free 25(OH)D, vitamin D-binding protein (DBP) and parathyroid hormone (PTH) as well as serum and urine biochemical parameters were performed before the intake and on Days 1, 3 and 7 after the administration. The studied groups had no significant differences in baseline parameters except that the patients with diabetes showed higher baseline levels of free 25(OH)D (
< 0.05). They also lacked a correlation between the measured and calculated free 25(OH)D in contrast to the patients from the control group (r = 0.41,
> 0.05 vs. r = 0.88,
< 0.05), possibly due to the glycosylation of binding proteins, which affects the affinity constant for 25(OH)D. The elevation of vitamin D levels after the administration of cholecalciferol was comparable in both groups, with slightly higher 25(OH)D
levels observed in the diabetes group throughout the study since Day 1 (
< 0.05). Overall, our data indicate that in patients with adequately controlled T1DM 25(OH)D
levels and the therapeutic response to cholecalciferol is similar to that in healthy individuals.
This study estimates diagnostic performance of late-night salivary cortisol (LNSC) as measured by automated electrochemiluminescence immunoassay (ECLIA), evaluates the clinical implication of two ...consecutive LNSC measurements, and compares its accuracy with enzyme-linked immunosorbent assay (ELISA) and serum cortisol after low-dose dexamethasone suppression test (DST) in obese and overweight patients referred for suspected Cushing’s syndrome (CS). One hundred twenty three consecutive obese and overweight referred patients and 98 healthy volunteers provided two saliva samples collected at 23:00 using a Salivette (Sarstedt, Germany), assayed by ECLIA (Cobas e601) and ELISA. The patients underwent DST and were further evaluated until CS was pathologically confirmed (
n
= 45) or excluded. Diagnostic performance of LNSC was evaluated by receiver operating characteristic (ROC) analysis. The total areas under the curve (AUC) were calculated to compare the different tests. We found that a cut-off value of 9.4 nmol/l can differentiate CS among obese and overweight patients with sensitivity of 84.4 % (95% CI 71.2–92.2), specificity of 92.3 % (95% CI 84.2–96.4), and diagnostic odds ratio of 65.1 (95% CI 20.4–207.6). No difference was found between AUCs from the first, second, and the mean from the two LNSC measurements (ECLIA), LNSC (ELISA), or DST. The single LNSC (ECLIA) and DST improved the sensitivity and specificity for concordant results up to 100 and 97.4 %, respectively. In conclusion, due to its automation and its comparable diagnostic performance, ECLIA is preferable as a first-line LNSC screening test for CS. The initial use of single LNSC followed by DST provides better diagnostic performance for concordant results.
In memory of Maria I. Bronstein Rozhinskaya, Liudmila Y.
Klinicheskai͡a︡ i ėksperimentalʹnai͡a︡ tireoidologii͡a,
04/2019, Letnik:
14, Številka:
4
Journal Article
Recenzirano
Odprti dostop
On June 14, 2018, at the age of 85, Maria Bronstein, a remarkable pathologist, died. The entire professional life of M. Bronstein was associated with the Endocrinology Research Centre (the Institute ...of Experimental Endocrinology and Chemistry of Hormones of the Russian Academy of Medical Sciences).
findings from the previously conducted studies indicate altered regulatory mechanisms of calcium and vitamin D metabolism in obese patients and a role for bariatric surgery in regulating vitamin D ...metabolism; however, the available data is controversial and does not provide an adequate understanding of the subject.
we evaluated serum parameters of vitamin D and mineral metabolism (vitamin D metabolites (25(OH)D
, 25(OH)D
, 1,25(OH)
D
, 3-epi-25(OH)D
, and 24,25(OH)
D
), vitamin D-binding protein (DBP), free 25(OH)D, fibroblast growth factor 23 (FGF-23), parathyroid hormone (PTH), total calcium, albumin, phosphorus, creatinine, magnesium) in 30 patients referred for bariatric surgery in comparison with 30 healthy volunteers of similar age, sex and baseline 25(OH)D
. Patients were also followed up with repeated laboratory assessments 3 months and 6 months after surgery. During the first 3 months, patients were prescribed high-dose cholecalciferol therapy (50,000 IU per week), with subsequent correction based on the results of the 3-month visit examination.
Preoperatively, patients with morbid obesity were characterized by a high prevalence of vitamin D deficiency (median 25(OH)D
level 11.9 (6.8; 22.2) ng/mL), significantly lower levels of active vitamin D metabolite 1,25(OH)
D
(20 (10; 37) vs. 39 (33; 50) pg/mL,
< 0.001), lower serum albumin-adjusted calcium levels (2.24 (2.20; 2.32) vs. 2.31 (2.25; 2.35) mmol/L,
= 0.009) and magnesium levels (0.79 (0.72; 0.82) vs. 0.82 (0.78; 0.85) mmol/L,
= 0.043) with simultaneous similar PTH levels (
= 0.912), and higher DBP levels (328 (288; 401) vs. 248 (217; 284) mg/L,
< 0.001). The 25(OH)D
levels remained suboptimal (24.5 (14.7; 29.5) ng/mL at the 3-month visit and 17.9 (12.4; 21.0) ng/mL at the 6-month visit,
= 0.052) despite recommended high-dose cholecalciferol supplementation. Patients also demonstrated an increase in 1,25(OH)
D
levels (38 (31; 52) pg/mL at the 3-month visit and 49 (29; 59) pg/mL at the 6-month visit,
< 0.001) without a change in PTH or calcium levels during the follow-up.
our results of a comprehensive laboratory evaluation of vitamin D status and mineral metabolism in patients undergoing bariatric surgery highlight the importance of improving current clinical guidelines, as well as careful monitoring and education of patients.
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