Background: Components of metabolic syndrome can be observed in patients with primary hyperparathyroidism (PHPT). The link between these disorders remains unclear due to the lack of relevant experimental models and the heterogeneity of examined groups. The effect of surgery on metabolic abnormalities is also controversial. We conducted a comprehensive assessment of metabolic parameters in young patients with PHPT. Methods: One-center prospective comparative study was carried out. The participants underwent a complex biochemical and hormonal examination, a hyperinsulinemic euglycemic and hyperglycemic clamps, a bioelectrical impedance analysis of the body composition before and 13 months after parathyroidectomy compared to sex-, age- and body mass index matched healthy volunteers. Results: 45.8% of patients (n = 24) had excessive visceral fat. Insulin resistance was detected in 54.2% of cases. PHPT patients had higher serum triglycerides, lower M-value and higher C-peptide and insulin levels in both phases of insulin secretion compared to the control group (p < 0.05 for all parameters). There were tendencies to decreased fasting glucose (p = 0.031), uric acid (p = 0.044) and insulin levels of the second secretion phase (p = 0.039) after surgery, but no statistically significant changes of lipid profile and M-value as well as body composition were revealed. We obtained negative correlations between percent body fat and osteocalcin and magnesium levels in patients before surgery. Conclusion: PHPT is associated with insulin resistance that is the main risk factor of serious metabolic disorders. Surgery may potentially improve carbohydrate and purine metabolism.

BACKGROUND: Vitamin D (25-hydroxyvitamin D [25(ОН)D]) deficiency (<20 ng/mL) and insufficiency (20–29 ng/mL) are common in primary hyperparathyroidism (PHPT), but data regarding the vitamin D metabolism in this population is limited.AIM: The aim of this study is to estimate the vitamin D metabolites and their relationship with the main parameters of phosphorus-calcium metabolism in patients with PHPT at baseline and on the background of a single dose of cholecalciferol 150,000 IU.MATERIALS AND METHODS: A single-center interventional, dynamic, prospective, comparative study has been carried out. The study included 54 participants, divided into two groups: the 1st group included 27 patients with confirmed PHPT, the 2nd control group (n = 27), matched on gender (p = 0.062). The study included 4 visits; the baseline laboratory examination and a bolus dose of cholecalciferol were performed at the visit 1, the subsequent visits included a dynamic laboratory examination.RESULTS: Vitamin D deficiency (<20 ng/ml) was detected in 69% of patients with PHPT. In the PHPT group (before cholecalciferol therapy), there was a direct association of 1.25(OH)₂ D₃ with albumin-corrected and ionized calcium, as well as between the 25(OH)D₃ /24.25(OH)₂ D₃ ratio with PTH and magnesium. After taking of cholecalciferol, the levels of 1.25(OH)₂ D₃ and 25(OH)D₃ /24.25(OH)₂ D₃ were significantly increased, and the levels of 25(OH)D₃ /1.25(OH)₂ D₃ were significantly declined at all visits among patients with PHPT. The common 25(OH)D level was comparable to the control group, however the levels of 1,25(OH)₂ D₃ in patients with PHPT were 55% higher at baseline, and after taking of cholecalciferol 150,000 IU. They remained increased by 3–7 days by an additional 23–36%, significantly higher than those in the control group: 44%, 74% and 65%, at visits 2, 3 and 4, respectively (p<0.05). The taking of 150,000 IU cholecalciferol in the PHPT group did not lead to a significant increase in hypercalcemia and hypercalciuria, which indicates the safety of this dose in patients with mild hypercalcemia (albumin corrected calcium <3 mmol/l). None of the study participants experienced any side effects.CONCLUSION: The completely comprehensive assessment of vitamin D metabolites was carried out for the first time in patients with PHPT before and after using a bolus dose of cholecalciferol. The results confirmed the differences of vitamin D metabolism in chronic excessive secretion of PTH compared to control group, which is new data in the pathogenesis of the disease, and can be used to develop optimal regimens for cholecalciferol taking in this population.

According to available research, chronic hypoparathyroidism is a relatively rare disease characterized by low serum calcium levels and the absence or deficiency of parathyroid hormone. The chronic course of the disease is associated with the multicomponent medical therapy, careful dynamic monitoring to reduce the risks of various complications in different organs and systems as well as disability and mortality.The Russian registry of patients with chronic postsurgical and nonsurgical hypoparathyroidism has started its work in 2020, based on data of the Endocrinology Research Centre. The main goals of the Registry are the assessment of the actual prevalence, incidence of hypoparathyroidism, the key epidemiological characteristics, the analysis of the clinical features and medical therapy of chronic hypoparathyroidism in Russian Federation.This article covers all objectives of this project, the methodology for maintaining the registry of chronic postsurgical and nonsurgical hypoparathyroidism, the analytical possibilities of its use, including the integration of a decision support system designed to help specialists in real clinical practice follow the algorithms for diagnosis and treatment of the disease, approved by clinical guidelines.The registry of chronic postsurgical and nonsurgical hypoparathyroidism is located on a single platform for the registers of endocrinopathies, regulated by the Endocrinology Research Centre (http://gipopt.clin-reg.ru/).

BACKGROUND: Timely referral of patients for genetic testing to rule out MEN1-associated primary PHPT is important factor in determining treatment strategy and prognosis. In the context of the limited availability of genetic testing, the search for clinical markers indicative of MEN1 gene mutations remains an extremely relevant task.AIM: To determine the diagnostic value of clinical features of primary PHPT in young patients for predicting the presence of MEN1 gene mutations.MATERIALS AND METHODS: A single-center, prospective study was conducted at the Endocrinology Research Centre, involving 273 patients with PHPT in the period 2015–2022. Based on the results of genetic and laboratory tests, patients were divided into three groups: those with MEN1 gene mutations (MEN+ group, n=71), those without MEN1 gene mutations — isolated sporadic PHPT (MEN- group, n=158), and patients with PHPT and associated endocrine gland disorders — MEN-1 syndrome phenocopies (PHEN group, n=32). Subgroups of patients younger than 40 years of age were also identified. Comparative analysis was performed among the independent groups and subgroups, and logistic regression analysis was used to develop a mathematical model for predicting the probability of the presence of MEN1 gene mutation.RESULTS: Patients in the MEN+ and MEN- groups were comparable by gender and age at manifestation, as well as calcium-phosphorus metabolism parameters and PHPT complications. In the PHEN group, PHPT manifested at older age compared to the other groups (p<0.001 for all), with lower total calcium levels and a trend toward lower iPTH concentrations. The MEN+ group had a significantly higher frequency of multiglandular parathyroid (PG) involvement, PHPT recurrence, and positive family history compared to the MEN- and PHEN groups. Histologically, adenomas predominated in the PHEN and MEN- groups (92% and 94%, respectively), whereas hyperplasia of PGs were more common in the MEN+ group (49%). None of the PHEN patients had all three «classic» components of the MEN-1 syndrome, and the clinical course of PHPT was similar to that of the MEN- group. These differences were also observed in the subgroups of patients younger than 40 years, which formed the basis for the development of a mathematical model. The logistic regression equation for predicting the probability of the presence of the MEN1 gene mutation included eight predictors, with a diagnostic sensitivity of 96% and specificity of 98%.CONCLUSION: Based on the analysis performed, eight hereditary predictors of PHPT within the MEN-1 syndrome were identified. A mathematical model was developed to predict the presence of the MEN1 gene mutation in patients, which demonstrated high classification performance on the training dataset. Further refinement of the model will help improve the quality of medical care for patients with PHPT.

AIM. To study the effect of the non-calorie sweetener erythritol and the combination of erythritol and sucrose on postprandial secretion of insulin and peptide-YY (PYY).MATERIALS AND METHODS. A comparative study was conducted to assess the effect of erythritol, sucrose and a combination of erythritol and sucrose on postprandial glucose, IRI and PYY levels. The participants were selected from among healthy volunteers, aged 18 to 35 years. If the participants met the selection criteria, further stages of the study were carried out. During the study, each participant took a solution of sucrose 75 g, erythritol 75 g or a mixture of sucrose and erythritol (75 g and 25 g, respectively). Further determination of glucose and insulin was carried out every 30 minutes, so glucose, insulin and PYY values were determined initially and at the 30th, 60th, 90th and 120th minutes.RESULTS. Data were obtained confirming the absence of the effect of erythritol on postprandial secretion of insulin and glucose. In our work, we also demonstrated a decrease in postprandial glycemia when taking sucrose and erythritol together. Sucrose and erythritol equally stimulated PYY secretion.CONCLUSION. Our data show that erythritol can be considered as an optimal sugar substitute in people with impaired carbohydrate metabolism and obesity.

BACKGROUND. Chronic hypoparathyroidism (HypoPT) is a relatively rare endocrine disorder. Adequate control of the disease requires the prescription of lifelong multicomponent therapy. Lack of sustained compensation of HypoPT is associated with the development of both early and delayed complications, including functional and structural renal pathology, cataracts, cerebral calcification, cardiac rhythm and/or conduction disorders, and others.AIM. To study the associations of clinical, laboratory and instrumental parameters, as well as the medical therapy, with long-term complications of chronic HypoPT.MATERIALS AND METHODS. The observational, continuous study was based on the data of the Russian Registry of Patients with Chronic Postoperative and Nonsurgical HypoPT; 1776 patients from 81 regions of the Russian Federation were included in the study.RESULTS. In the study population, 26,3% of patients (n=467) had at least one of the HypoPT complications, among them nephrolithiasis/nephromicrolithiasis was diagnosed in 33,4%. Nephrocalcinosis was observed in 10,7% and was more often bilateral (93,5%). In 17,4% of patients there was a significant decrease in GFR, corresponding to CKD stages 3a-5. Cataract was present in 34,7% of patients with chronic HypoPT. Statistically significant associations were found for disease duration with impaired renal filtration function (p<0,001), nephrocalcinosis/nephrolithiasis (p=0,001) and cataract (p<0,001). Patients with impaired renal function had higher serum ionized calcium level (p=0,0071) and lower phosphorus level (p=0,002). Cataract was predominantly diagnosed in patients of older age group (p<0,001), predominant in the presence of hypocalcemia by ionized calcium level (p=0,001). In patients undergoing brain MSCT for neurological symptoms, basal ganglia calcifications were detected in more than half of the cases (56,2%). Brain calcification was associated with younger patient age (p<0,001), hyperphosphatemia (p<0,001), hypomagnesemia (p=0,010). Statistically significant associations were observed between calcification of brain structures and higher doses of alfacalcidol and calcium carbonate (p=0,007).CONCLUSION. The analysis of the database revealed a number of associations between clinical, laboratory and instrumental parameters and long-term complications of HypoPT. The most significant factors in the development of renal pathology and cataracts are the duration of the disease, as well as off-target indicators of calcium-phosphorus metabolism.