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  • Abstract: Hyperparathyroidism x
  • Abstract: Vitamin D x
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Stan Ursem Department of Clinical Chemistry, Amsterdam Gastroenterology & Metabolism, Amsterdam UMC, Vrije Universiteit Amsterdam, Endocrine Laboratory, Amsterdam, Netherlands

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Vito Francic Division of Endocrinology and Diabetology, Department of Internal Medicine, Endocrinology Lab Platform, Medical University of Graz, Graz, Austria

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Martin Keppel University Institute for Medical and Chemical Laboratory Diagnostics, Paracelsus Medical University, Salzburg, Austria

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Verena Schwetz Division of Endocrinology and Diabetology, Department of Internal Medicine, Endocrinology Lab Platform, Medical University of Graz, Graz, Austria

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Christian Trummer Division of Endocrinology and Diabetology, Department of Internal Medicine, Endocrinology Lab Platform, Medical University of Graz, Graz, Austria

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Marlene Pandis Division of Endocrinology and Diabetology, Department of Internal Medicine, Endocrinology Lab Platform, Medical University of Graz, Graz, Austria

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Felix Aberer Division of Endocrinology and Diabetology, Department of Internal Medicine, Endocrinology Lab Platform, Medical University of Graz, Graz, Austria

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Martin R Grübler Division of Endocrinology and Diabetology, Department of Internal Medicine, Endocrinology Lab Platform, Medical University of Graz, Graz, Austria

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Nicolas D Verheyen Division of Cardiology, Department of Internal Medicine, Medical University of Graz, Graz, Austria

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Winfried März Synlab Academy, Synlab Holding Germany GmbH, München, Germany

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Andreas Tomaschitz Specialist Clinic of Rehabilitation Bad Gleichenberg, Bad Gleichenberg, Austria

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Stefan Pilz Division of Endocrinology and Diabetology, Department of Internal Medicine, Endocrinology Lab Platform, Medical University of Graz, Graz, Austria

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Barbara Obermayer-Pietsch Division of Endocrinology and Diabetology, Department of Internal Medicine, Endocrinology Lab Platform, Medical University of Graz, Graz, Austria

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Annemieke C Heijboer Department of Clinical Chemistry, Amsterdam Gastroenterology & Metabolism, Amsterdam UMC, Vrije Universiteit Amsterdam, Endocrine Laboratory, Amsterdam, Netherlands
Department of Clinical Chemistry, Amsterdam Gastroenterology & Metabolism, Amsterdam UMC, University of Amsterdam, Endocrine Laboratory, Amsterdam, Netherlands

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Objective

PTH can be oxidised in vivo, rendering it biologically inactive. Non-oxidised PTH (n-oxPTH) may therefore give a better image of the hormonal status of the patient. While vitamin D supplementation decreases total PTH (tPTH) concentration, the effect on n-oxPTH concentration is unexplored. We investigated the effect of vitamin D on n-oxPTH concentration in comparison to tPTH and compared the correlations between parameters of calcium, bone and lipid metabolism with n-oxPTH and tPTH.

Methods

N-oxPTH was measured in 108 vitamin D-insufficient (25(OH)D <75 nmol/L) hypertensive patients, treated with vitamin D (2800 IE daily) or placebo for 8 weeks in the Styrian Vitamin D Hypertension Trial (NCT02136771). We calculated the treatment effect and performed correlation analyses of n-oxPTH and tPTH with parameters of calcium, bone and lipid metabolism and oxidative stress.

Results

After treatment, compared to placebo, 25(OH)D concentrations increased, tPTH decreased by 9% (P < 0.001), n-oxPTH by 7% (P = 0.025) and the ratio of n-oxPTH/tPTH increased (P = 0.027). Changes in phosphate and HDL concentration correlated with changes in n-oxPTH, but not tPTH.

Conclusions

tPTH and n-oxPTH decrease upon vitamin D supplementation. Our study suggests that vitamin D supplementation reduces the oxidation of PTH, as we observed a small but significant increase in the non-oxidised proportion of PTH upon treatment. In addition, we found that changes in phosphate and HDL concentration showed a relationship with changes in n-oxPTH, but not tPTH. This may be explained by the biological activity of n-oxPTH. Further research should be carried out to establish the clinical relevance of n-oxPTH.

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Mirjam M Oosterwerff Departments of Internal Medicine, Epidemiology and Biostatistics, Public and Occupational Health, Endocrine Section

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Rosa Meijnen Departments of Internal Medicine, Epidemiology and Biostatistics, Public and Occupational Health, Endocrine Section

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Natasja M Van Schoor Departments of Internal Medicine, Epidemiology and Biostatistics, Public and Occupational Health, Endocrine Section

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Dirk L Knol Departments of Internal Medicine, Epidemiology and Biostatistics, Public and Occupational Health, Endocrine Section

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Mark H H Kramer Departments of Internal Medicine, Epidemiology and Biostatistics, Public and Occupational Health, Endocrine Section

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Mireille N M Van Poppel Departments of Internal Medicine, Epidemiology and Biostatistics, Public and Occupational Health, Endocrine Section

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Paul Lips Departments of Internal Medicine, Epidemiology and Biostatistics, Public and Occupational Health, Endocrine Section

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E Marelise W Eekhoff Departments of Internal Medicine, Epidemiology and Biostatistics, Public and Occupational Health, Endocrine Section

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Vitamin D deficiency is highly prevalent among non-western immigrants in The Netherlands and associated with poor physical performance. The aim of this study was to assess the effect of vitamin D supplementation on physical performance, exercise capacity, and daily physical activity in vitamin D-deficient, overweight non-western immigrants. A randomized double-blind, placebo-controlled trial was conducted to assess the effect of vitamin D on physical performance. A total of 130 participants were included. Eligibility criteria included overweight (BMI >27 kg/m2), 25-hydroxy vitamin D (25(OH)D) ≤50 nmol/l, and an age range of 20–65 years. The intervention group received 1200 IU vitamin D3 daily for 4 months; the control group received placebo. Both groups received 500 mg calcium daily. Outcome measures included physical performance (physical performance score), exercise capacity (a 6-min walk test (6-MWT)), and daily physical activity (questionnaire and accelerometer). There was no significant effect on physical performance, exercise capacity, or physical activity in the intention to treat analysis. In an explorative post hoc analysis restricted to participants reaching a serum 25(OH)D concentration of >60 nmol/l after intervention, there was an improvement of 19 m in the 6-MWT compared with the control group (P=0.053). Moderate dose vitamin D supplementation did not significantly improve physical performance, exercise capacity, or physical activity. However, when 25(OH)D concentrations reached >60 nmol/l after intervention, there was a borderline significant improvement in exercise capacity. Although the clinical relevance is not clear, this is a promising result, as all participants were overweight and did not improve their overall activity levels.

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Niek F Dirks Atalmedial Diagnostics Centre, Spaarne Gasthuis, Haarlem, The Netherlands
Department of Clinical Chemistry, Hematology and Immunology, Noordwest Ziekenhuis, Alkmaar, The Netherlands

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Etienne Cavalier Department of Clinical Chemistry, University of Liège, CHU de Liège, Liège, Belgium

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Annemieke C Heijboer Amsterdam UMC location Vrije Universiteit Amsterdam, Department of Clinical Chemistry, Endocrine Laboratory, Boelelaan, Amsterdam, The Netherlands
Amsterdam Gastroenterology, Endocrinology & Metabolism, Amsterdam, The Netherlands
Amsterdam UMC location University of Amsterdam, Department of Clinical Chemistry, Endocrine Laboratory, Amsterdam, The Netherlands
Amsterdam Reproduction & Development Research Institute, Amsterdam, The Netherlands

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The measurement of vitamin D metabolites aids in assessing vitamin D status and in diagnosing disorders of calcium homeostasis. Most laboratories measure total 25-hydroxyvitamin D (25(OH)D), while others have taken the extra effort to measure 25(OH)D2 and 25(OH)D3 separately and additional metabolites such as 1,25-dihydroxyvitamin D and 24,25-dihydroxyvitamin D. The aim of this review is to provide an updated overview of the main markers of vitamin D metabolism, define the intended measurands, and discuss the advantages and disadvantages of the two most widely used assays, automated assays and liquid chromatography–tandem mass spectrometry (LC-MS/MS). Whether using the easy and fast automated assays or the more complex LC-MS/MS, one should know the pitfalls of the used technique in order to interpret the measurements. In conclusion, automated assays are unable to accurately measure 25(OH)D in all patient groups, including persons using D2. In these cases, an LC-MS/MS method, when appropriately developed and standardized, produces a more reliable measurement.

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Laura P B Elbers Department of Internal Medicine, Medical Center Slotervaart, Amsterdam, the Netherlands
Department of Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands

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Marije Wijnberge Department of Internal Medicine, Medical Center Slotervaart, Amsterdam, the Netherlands
Department of Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
Laboratory of Experimental Intensive Care and Anesthesiology, Academic Medical Center, University of Amsterdam, the Netherlands

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Joost C M Meijers Department of Experimental Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
Department of Plasma Proteins, Sanquin Research, Amsterdam, the Netherlands

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Dennis C W Poland Clinical Chemistry Laboratory, Medical Center Slotervaart, Amsterdam, the Netherlands

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Dees P M Brandjes Department of Internal Medicine, Medical Center Slotervaart, Amsterdam, the Netherlands
Department of Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands

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Eric Fliers Department of Endocrinology and Metabolism, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands

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Victor E A Gerdes Department of Internal Medicine, Medical Center Slotervaart, Amsterdam, the Netherlands
Department of Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands

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Introduction

Abnormal coagulation tests have been observed in patients with primary hyperparathyroidism (HPT) suggesting a prothrombotic effect of parathyroid hormone (PTH). Vitamin D deficiency (VIDD) is the most frequent cause of secondary HPT. Aim of our study was to investigate the influence of HPT secondary to moderate-to-severe VIDD and vitamin D replacement on the coagulation and fibrinolysis system.

Subjects and methods

Prospective cohort study of patients with vitamin D <25 nmol/L with and without HPT, and a control group of patients on vitamin D suppletion. At baseline and after 2 months of vitamin D suppletion (900,000 IU in 2 months), endocrine and coagulation markers were measured.

Results

59 patients with VIDD of which 34 had secondary HPT and 36 controls were included. After 2 months of suppletion, vitamin D increased by 399% (VIDD with HPT), 442% (all patients with VIDD) and 6% (controls). PTH decreased by 34% (VIDD with HPT, P < 0.01 for decrease), 32% (all VIDD, P < 0.01) and increased by 8% in the controls (P-values: <0.01 for relative changes between VIDD with HPT or all VIDD patients vs controls). Relative changes in PT, aPTT, fibrinogen, Von Willebrand factor, factors VII, VIII and X, thrombin generation, TAFI, clot-lysis time and d-dimer were not different between patients with VIDD with HPT or all VIDD vs controls.

Discussion

Secondary HPT due to VIDD does not have a prothrombotic effect. In contrast with previous reports, PTH does not seem to influence coagulation or fibrinolysis, which is relevant because of the high prevalence of VIDD.

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Mengting Yin Sichuan University West China Hospital, Chengdu, China

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Qianhui Liu Sichuan University West China Hospital, Chengdu, China

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Qingzhong Wang Jintang First People’s Hospital, West China Hospital Sichuan University Jingtang Hospital, Chengdu, China

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Yong He Sichuan University West China Hospital, Chengdu, China

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Haolan Song Sichuan University West China Hospital, Chengdu, China

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Xin Nie Sichuan University West China Hospital, Chengdu, China

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Guixing Li Sichuan University West China Hospital, Chengdu, China

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Background

The diagnosis of primary hyperparathyroidism (PHPT) remains a challenge because of increased asymptomatic PHPT or patients with normocalcaemic PHPT (NPHPT). In addition, some primary hospitals in China have no equipment to measure parathyroid hormone (PTH) levels. Therefore, an additional, simple, and inexpensive laboratory biochemical marker is urgently needed. The calcium/phosphate (Ca/P) ratio and chloride/phosphate (Cl/P) ratio have been proposed as suitable tools to diagnose PHPT in Europe; however, the Ca/P ratio has never been tested in China. We aimed to conduct a confirmatory study to explore the diagnostic performance of the Ca/P ratio for PHPT in China.

Methods

From January 2015 to December 2020, a total of 155 patients who underwent parathyroidectomy (143 PHPT patients and 12 NPHPT patients) and 153 controls were enrolled in this single-center , retrospective study. Serum calcium, phosphate, parathyroid hormone, 25-hydroxyvitamin vitamin D (25(OH) vitamin D), chloride, alanine transaminase (ALT), aspartate aminotransaminase (AST), estimated glomerular filtration rate (eGFR), and creatinine levels were recorded for all the study participants. Pairwise comparisons were made between groups, and the diagnostic performance of the Ca/P ratio was determined using receiver-operating characteristic (ROC) analysis.

Results

Patients with PHPT had a higher Ca/P ratio than controls (P < 0.001). A Ca/P ratio above 2.94 with a sensitivity of 95.5% and specificity of 98.7% can distinguish PHPT patients from healthy individuals. This index was positively correlated with the PTH level (r = 0.875, P < 0.001).

Conclusion

The Ca/P ratio is an ideal and inexpensive indicator for diagnosing PHPT in China when using a cut-off value of 2.94.

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Melissa Braga Department of Internal Medicine, Charles R. Drew University of Medicine and Science, Los Angeles, California, USA

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Zena Simmons Department of Health & Life Sciences, Charles R. Drew University of Medicine and Science, Los Angeles, California, USA

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Keith C Norris Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, USA

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Monica G Ferrini Department of Internal Medicine, Charles R. Drew University of Medicine and Science, Los Angeles, California, USA
Department of Health & Life Sciences, Charles R. Drew University of Medicine and Science, Los Angeles, California, USA
Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, USA

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Jorge N Artaza Department of Internal Medicine, Charles R. Drew University of Medicine and Science, Los Angeles, California, USA
Department of Health & Life Sciences, Charles R. Drew University of Medicine and Science, Los Angeles, California, USA
Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, USA

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Skeletal muscle wasting is a serious disorder associated with health conditions such as aging, chronic kidney disease and AIDS. Vitamin D is most widely recognized for its regulation of calcium and phosphate homeostasis in relation to bone development and maintenance. Recently, vitamin D supplementation has been shown to improve muscle performance and reduce the risk of falls in vitamin D deficient older adults. However, little is known of the underlying molecular mechanism(s) or the role it plays in myogenic differentiation. We examined the effect of 1,25-D3 on myogenic cell differentiation in skeletal muscle derived stem cells. Primary cultures of skeletal muscle satellite cells were isolated from the tibialis anterior, soleus and gastrocnemius muscles of 8-week-old C57/BL6 male mice and then treated with 1,25-D3. The efficiency of satellite cells isolation determined by PAX7+ cells was 81%, and they expressed VDR. Incubation of satellite cells with 1,25-D3 induces increased expression of: (i) MYOD, (ii) MYOG, (iii) MYC2, (iv) skeletal muscle fast troponin I and T, (v) MYH1, (vi) IGF1 and 2, (vii) FGF1 and 2, (viii) BMP4, (ix) MMP9 and (x) FST. It also promotes myotube formation and decreases the expression of MSTN. In conclusion, 1,25-D3 promoted a robust myogenic effect on satellite cells responsible for the regeneration of muscle after injury or muscle waste. This study provides a mechanistic justification for vitamin D supplementation in conditions characterized by loss of muscle mass and also in vitamin D deficient older adults with reduced muscle mass and strength, and increased risk of falls.

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Malachi J McKenna Metabolism Laboratory, Department of Endocrinology, School of Medicine and Medical Sciences, St Vincent's University Hospital, Elm Park, Dublin 4, Ireland
Metabolism Laboratory, Department of Endocrinology, School of Medicine and Medical Sciences, St Vincent's University Hospital, Elm Park, Dublin 4, Ireland
Metabolism Laboratory, Department of Endocrinology, School of Medicine and Medical Sciences, St Vincent's University Hospital, Elm Park, Dublin 4, Ireland

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Barbara F Murray Metabolism Laboratory, Department of Endocrinology, School of Medicine and Medical Sciences, St Vincent's University Hospital, Elm Park, Dublin 4, Ireland

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Myra O'Keane Metabolism Laboratory, Department of Endocrinology, School of Medicine and Medical Sciences, St Vincent's University Hospital, Elm Park, Dublin 4, Ireland

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Mark T Kilbane Metabolism Laboratory, Department of Endocrinology, School of Medicine and Medical Sciences, St Vincent's University Hospital, Elm Park, Dublin 4, Ireland

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Background

The Institute of Medicine 2011 Report on Dietary Reference Intakes for Calcium and Vitamin D specified higher intakes for all age groups compared to the 1997 report, but also cautioned against spurious claims about an epidemic of vitamin D deficiency and against advocates of higher intake requirements. Over 40 years, we have noted marked improvement in vitamin D status but we are concerned about hypervitaminosis D.

Objective

We sought to evaluate the 25-hydroxyvitamin D (25OHD) trend over 20 years.

Design

We retrieved all results of serum 25OHD from 1993 to 2013 (n=69 012) that was trimmed to one sample per person (n=43 782). We conducted a time series analysis of the monthly averages for 25OHD using a simple sequence chart and a running median smoothing function. We modelled the data using univariate auto-regressive integrated moving average (ARIMA) and forecast 25OHD levels up to 2016.

Results

The time series sequence chart and smoother function demonstrated a steady upward trend with seasonality. The yearly average 25OHD increased from 36.1 nmol/l in 1993 to 57.3 nmol/l in 2013. The ARIMA model was a good fit for the 25OHD time series; it forecasted monthly average 25OHD up to the end of 2016 with a positive stationary R 2 of 0.377.

Conclusions

Vitamin D status improved over the past 40 years, but there remains a dual problem: there are groups at risk of vitamin D deficiency who need public health preventative measures; on the other hand, random members of the population are taking unnecessarily high vitamin D intakes for unsubstantiated claims.

Open access
Tomás P Griffin Centre for Endocrinology, Diabetes and Metabolism, Saolta University Health Care Group (SUHCG), Galway University Hospitals (GUH), Galway, Ireland
Regenerative Medicine Institute at CÚRAM SFI Research Centre, School of Medicine, National University of Ireland Galway (NUIG), Galway, Ireland

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Caroline M Joyce Department of Clinical Biochemistry, Cork University Hospital, Cork, Ireland

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Sumaya Alkanderi Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK

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Liam M Blake Department of Clinical Biochemistry, SUHCG, GUH, Galway, Ireland

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Derek T O’Keeffe Centre for Endocrinology, Diabetes and Metabolism, Saolta University Health Care Group (SUHCG), Galway University Hospitals (GUH), Galway, Ireland

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Delia Bogdanet Centre for Endocrinology, Diabetes and Metabolism, Saolta University Health Care Group (SUHCG), Galway University Hospitals (GUH), Galway, Ireland

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Md Nahidul Islam Regenerative Medicine Institute at CÚRAM SFI Research Centre, School of Medicine, National University of Ireland Galway (NUIG), Galway, Ireland
Department of Clinical Biochemistry, SUHCG, GUH, Galway, Ireland

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Michael C Dennedy Centre for Endocrinology, Diabetes and Metabolism, Saolta University Health Care Group (SUHCG), Galway University Hospitals (GUH), Galway, Ireland
Lambe Institute for Translational Research, School of Medicine, NUIG, Galway, Ireland

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John E Gillan Department of Histopathology, SUHCG, GUH, Galway, Ireland

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John J Morrison Department of Obstetrics and Gynaecology, SUHCG, GUH, Galway, Ireland

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Timothy O’Brien Centre for Endocrinology, Diabetes and Metabolism, Saolta University Health Care Group (SUHCG), Galway University Hospitals (GUH), Galway, Ireland
Regenerative Medicine Institute at CÚRAM SFI Research Centre, School of Medicine, National University of Ireland Galway (NUIG), Galway, Ireland

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John A Sayer Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
Newcastle upon Tyne NHS Hospitals Foundation Trust, Newcastle upon Tyne, UK
NIHR Newcastle Biomedical Research Centre, Newcastle upon Tyne, UK

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Marcia Bell Centre for Endocrinology, Diabetes and Metabolism, Saolta University Health Care Group (SUHCG), Galway University Hospitals (GUH), Galway, Ireland

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Paula M O’Shea Department of Clinical Biochemistry, SUHCG, GUH, Galway, Ireland

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Introduction

Inactivating mutations in CYP24A1, encoding vitamin D-24-hydroxylase, can lead to an accumulation of active vitamin D metabolites and consequent hypercalcaemia. Patient (infantile and adult) presentation is varied and includes mild-severe hypercalcaemia, hypercalciuria, nephrocalcinosis and nephrolithiasis. This study aimed to characterize the clinical and biochemical phenotypes of a family with two CYP24A1 missense variants.

Methods

The proband and seven family members underwent detailed clinical and biochemical evaluation. Laboratory measurements included serum calcium, intact parathyroid hormone (iPTH), vitamin D metabolites and urine calcium and creatinine.

Results

The proband presented during the second trimester of a planned pregnancy with flu-like symptoms. Laboratory tests showed elevated adjusted calcium of 3.27 (upper reference limit (URL: 2.30) mmol/L), suppressed iPTH (<6 ng/L), elevated 25(OH)D (264 (URL: 55) nmol/L) and elevated 1,25(OH)D (293 (URL: <280) pmol/L). Ionized calcium was 1.55 (URL: 1.28) mmol/L. Sanger sequencing revealed two heterozygous missense variants in the CYP24A1: p.(Arg439Cys), R439C and p.(Trp275Arg), W275R. The proband’s brother and sister had the same genotype. The brother had intermittent hypercalcaemia and hypervitaminosis D. Only the sister had a history of nephrolithiasis. The proband’s daughter and two nephews were heterozygous for the R439C variant. The proband and her brother frequently had elevated 25(OH)D:24,25(OH)2D ratios (>50) during follow-up.

Conclusions

W275R is a new pathogenic CYP24A1 mutation in compound heterozygotic form with R439C in this family.

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A Chinoy Royal Manchester Children’s Hospital, Manchester, UK

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M Skae Royal Manchester Children’s Hospital, Manchester, UK

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A Babiker King Abdullah Specialized Children’s Hospital, Riyadh, Saudi Arabia

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D Kendall Royal Preston Hospital, Preston, UK

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M Z Mughal Royal Manchester Children’s Hospital, Manchester, UK

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R Padidela Royal Manchester Children’s Hospital, Manchester, UK

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Background

Hypoparathyroidism is characterised by hypocalcaemia, and standard management is with an active vitamin D analogue and adequate oral calcium intake (dietary and/or supplements). Little is described in the literature about the impact of intercurrent illnesses on calcium homeostasis in children with hypoparathyroidism.

Methods

We describe three children with hypoparathyroidism in whom intercurrent illnesses led to hypocalcaemia and escalation of treatment with alfacalcidol (1-hydroxycholecalciferol) and calcium supplements.

Results

Three infants managed with standard treatment for hypoparathyroidism (two with homozygous mutations in GCMB2 gene and one with Sanjad-Sakati syndrome) developed symptomatic hypocalcaemia (two infants developed seizures) following respiratory or gastrointestinal illnesses. Substantial increases in alfacalcidol doses (up to three times their pre-illness doses) and calcium supplementation were required to achieve acceptable serum calcium concentrations. However, following resolution of illness, these children developed an increase in serum calcium and hypercalciuria, necessitating rapid reduction to pre-illness dosages of alfacalcidol and oral calcium supplementation.

Conclusion

Intercurrent illness may precipitate symptomatic hypocalcaemia in children with hypoparathyroidism, necessitating increase in dosages of alfacalcidol and calcium supplements. Close monitoring is required on resolution of the intercurrent illness, with timely reduction of dosages of active analogues of vitamin D and calcium supplements to prevent hypercalcaemia, hypercalciuria and nephrocalcinosis.

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Xiaoli Jin Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China

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Jiankang Shen Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China

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Tao Liu Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China

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Ru Zhou Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China

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Xunbo Huang Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China

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Tianxiang Wang Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China
Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China

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Weize Wu Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China
Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China

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Mingliang Wang Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China
Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China

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Rongli Xie Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China

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Jianming Yuan Department of General Surgery, Ruijin Hospital Lu Wan Branch, Shanghai Jiaotong University School of Medicine, Shanghai, China

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Objective

The aim was to explore the effects of preoperative calcium and activated vitamin D3 supplementation on post-thyroidectomy hypocalcemia and hypo-parathyroid hormone-emia (hypo-PTHemia).

Methods

A total of 209 patients were randomly divided into control group (CG) and experimental group (EG). Oral calcium and activated vitamin D3 supplementation were preoperatively administered to EG, whereas a placebo was administered to CG. Data on serum calcium, phosphorus, and PTH concentrations before operation, on postoperative day 1 (POPD1), at postoperative week 3 (POPW3), and on the length of postoperative hospitalization were collected.

Results

The serum calcium, phosphorus, and PTH concentrations, as well as the incidence of postoperative hypocalcemia and hypo-PTHemia, did not significantly differ between EG and CG. Subgroup analysis revealed that the serum calcium concentrations of the experimental bilateral thyroidectomy subgroup (eBTS) on POPD1 and POPW3 were higher than that of the control bilateral thyroidectomy subgroup (cBTS) (P < 0.05); the reduction of serum calcium in eBTS on POPD1 and POPW3 was less than those in cBTS (P < 0.05). However, significant differences were not observed between the unilateral thyroidectomy subgroups (UTS) (P > 0.05). Moreover, the incidence of postoperative hypocalcemia in cBTS on POPD1 was significantly higher than that in eBTS (65.9% vs 41.7%) (P < 0.05). The length of hospitalization in cBTS (3.55 ± 1.89 days) was significantly longer than that (2.79 ± 1.15 days) in eBTS (P < 0.05).

Conclusion

Short-term preoperative prophylactic oral calcium and activated vitamin D3 supplementation could effectively reduce the incidence of postoperative hypocalcemia and decrease the length of postoperative hospitalization in patients who have undergone bilateral thyroidectomy.

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