Acute pancreatitis and refractory hypercalcemia in the third trimester caused by parathyroid carcinoma.

BACKGROUND: Hypercalcemia can be a rare contributor to acute pancreatitis (AP) in pregnancy. This is primarily due to primary hyperparathyroidism (PHPT), resulting from parathyroid carcinoma. We exhibited a case report to analyze the diagnosis and treatment during the onset of hypercalcemia-induced AP. CASE PRESENTATION: A 32-year-old primigravida presented with acute pancreatitis near full-term gestation. Following a cesarean delivery, there was a reduction in serum amylase and peripancreatic exudate, but her serum calcium concentrations persistently elevated over 4.0 mmol/L. Interventions to lower the hypercalcemia were only temporarily effective, until a high serum parathyroid hormone (PTH) concentration of 1404 pg/mL was detected. Ultrasound revealed a 31 mm × 24 mm hypoechoic oval nodule in the left lower lobe of the thyroid gland. She underwent a parathyroidectomy, resulting in a dramatic decrease in serum PTH level, from preoperative levels of 2051 pg/mL to 299 pg/mL just 20 minutes after removal. Similarly, her serum calcium declined from 3.82 mmol/L to 1.73 mmol/L within 24 hours postoperatively. The final histopathology suggested parathyroid carcinoma. CONCLUSION: When refractory hypercalcemia is present, serum PTH levels should be measured to determine PHPT. Parathyroidectomy is the optimal strategy for alleviating hypercalcemia and clarifying the underlying pathology.

Primary hyperparathyroidism caused by a tiny mediastinal parathyroid adenoma with non-localising imaging studies.

Variations in parathyroid gland positions often cause failure in initial parathyroid adenoma surgery, especially when imaging fails to localise the adenoma. This report describes a female patient with primary hyperparathyroidism for which preoperative localisation studies did not determine the position of the hyperfunctioning gland. The initial approach with bilateral cervical exploration and intraoperative parathyroid hormone monitoring was performed unsuccessfully. A mediastinal adenoma was suspected due to meticulous negative neck exploration and repeated negative images for a neck adenoma. Subsequently, a second approach involving mediastinal exploration was performed. After the removal of remnant thymic tissue in the mediastinal space, a significant drop in intraoperative parathyroid hormone levels was achieved. The pathological result confirmed the presence of a tiny pathological parathyroid adenoma within the thymus. At 6 months follow-up, postoperative biochemical assessment was consistent with normal calcium and parathyroid hormone levels.

Normocalcemic primary hyperparathyroidism: From pathophysiology to clinical management.

Normocalcemic primary hyperparathyroidism (NPHPT), a variant of primary hyperparathyroidism (PHPT) characterized by persistently elevated parathyroid hormone (PTH) levels and normal serum calcium, has gained recognition as a substantial subset of PHPT cases. Despite its increasing prevalence, the precise pathophysiology and natural progression of NPHPT remain enigmatic. This in-depth literature review explores recent advancements in our understanding of NPHPT, encompassing pathophysiology, clinical presentation, diagnostic approaches, medical and surgical management options. By synthesizing this wealth of information, this review aims to contribute to a more nuanced and informed approach to the treatment of patients grappling with NPHPT. As our understanding of the condition continues to evolve, the knowledge gathered from this review has the potential to significantly enhance the quality of care and outcomes for individuals afflicted with NPHPT, ultimately improving their overall well-being and prognosis.

Pancreatitis with Intraabdominal Venous Thrombosis as an Initial Presentation of Parathyroid Adenoma: A Rare Clinical Presentation.

BACKGROUND Benign parathyroid adenoma is a cause of hypercalcemia, which can lead to acute pancreatitis. Patients with acute pancreatitis are at risk for venous thrombosis. This report describes a 34-year-old woman with hypercalcemia due to parathyroid adenoma and acute pancreatitis associated with splenic vein and superior mesenteric vein thrombosis. CASE REPORT A previously healthy 34-year-old woman presented with severe epigastric pain that radiated to the back, associated with vomiting. Her abdominal examination was soft and lax, with epigastric and left upper quadrant tenderness. Pancreatitis with splenic and superior mesenteric veins thrombosis was diagnosed. The diagnosis was confirmed by an elevated serum lipase level and contrast-enhanced computed tomography (CT) of abdomen. Her serum calcium level was elevated. However, further workup revealed elevated parathyroid hormone (PTH) levels and radiological imaging showed parathyroid adenoma. She was diagnosed with hypercalcemia-induced pancreatitis secondary to hyperparathyroidism with intraabdominal venous thrombosis. The patient was initially treated conservatively, and later underwent parathyroidectomy after her condition was stabilized. The patient is currently in good condition, after a 2-year follow-up period. CONCLUSIONS Acute pancreatitis and thrombosis secondary to primary hyperparathyroidism (PHPT) are rare, but can lead to potentially fatal complications, especially in patients without symptoms of PHPT. This report highlights the importance of recognizing that hypercalcemia associated with parathyroid adenoma can result in acute pancreatitis, leading to hypercoagulable states and inflammation of adjacent vessels, including the splenic and mesenteric veins. To the best of our knowledge, this is second case report of acute pancreatitis with intraabdominal venous thrombosis secondary to PHPT.

Hypercalcemia Associated with Pregnancy and Lactation.

Hypercalcemia during pregnancy is a risk for adverse maternal and fetal consequences. Although primary hyperparathyroidism is by far the most common etiology of hypercalcemia in pregnancy, an array of other etiologies of hypercalcemia associated with pregnancy and lactation have been described. Parathyroidectomy continues to be the preferred treatment for primary hyperparathyroidism. Medical management options are limited.

Do large parathyroid adenomas increase the risk of severe hypercalcemia?

<b><br>Introduction:</b> Primary hyperparathyroidism (PHPT) is mainly caused by parathyroid adenoma (PA). Rare variants of PA, weighing >2.0-3.5 g are called "large" or "giant" adenomas and account for about 1.5% of all PA.</br> <b><br>Aim:</b> The aim of this study was to compare normal-sized and large parathyroid lesions identifying risk factors for severe hypercalcemia.</br> <b><br>Materials and methods:</b> 27 patients with PHPT and parathyroid lesion ≥2.0 cm3 (study group) were compared with 73 patients with PHPT and lesion < 2.0 cm³ (control group). In both groups, the majority were women (81.5% - study group, 90.5% - control group, gender ratios 4.4:9.1, respectively). The patients were examined preoperatively and postoperatively: PTH, creatine, calcium, and phosphate serum and urine concentrations, and calcidiol serum levels were assessed. Preoperative ultrasonography (US) was performed.</br> <b><br>Results:</b> Patients with larger parathyroid lesions had signifficantly higher PTH and calcium serum concentrations and lower serum phosphate and calcidiol concentrations. There were no statistically significant differences in the concentration of creatine in serum and urine, calciuria, or tubular reabsorption of phosphorus (TRP). US relatively underestimated the parathyroid volume by about 0.3-0.4 mL (10% in larger lesions and 43% in smaller ones).</br> <b><br>Conclusions:</b> Due to higher PTH and calcium levels, larger parathyroid adenomas may constitute a higher risk of severe hypercalcemia. In general, US underestimated the parathyroid volume.</br>.

Primary Hyperparathyroidism: Part One: Evaluation.

Primary hyperparathyroidism (PHPT) is a disorder characterized by the autonomous overproduction of parathyroid hormone (PTH) that leads to hypercalcemia, multiple clinical sequelae, and heterogenous presentation. Whether PHPT is caused by a single benign adenoma (85%), multiglandular disease (15%), or parathyroid carcinoma (1%), surgery is the definitive treatment.

Primary Hyperparathyroidism during Pregnancy: Two Tales with Different Outcomes.

Primary hyperparathyroidism (PHPT) is rare in pregnancy. This condition is challenging to diagnose and manage due to the limited diagnostic and therapeutic options that are safe during pregnancy. If not diagnosed and managed in a timely manner, serious maternal and foetal complications may occur. We report two cases, one with surgical intervention and one without, to show the importance of timely surgical intervention and discuss the challenges in the management of PHPT in pregnancy.

Identification of novel risk factors for postoperative severe hypocalcemia in patients with primary hyperparathyroidism undergoing parathyroidectomy: a case control study.

BACKGROUND: Patients with primary hyperparathyroidism (PHPT) are at risk for severe hypocalcemia (SH) following parathyroidectomy (PTX), but limited data exist on the predictors of SH. We aimed to identify risk factors for early postoperative SH after PTX in patients with PHPT and to evaluate the predictive value of clinical parameters. METHODS: A retrospective review of patients with PHPT who underwent PTX between January 2010 and December 2022 was performed. A total of 46 patients were included in the study, with 15 (32.6%) experiencing postoperative SH, 19 (41.3%) having calculi in the ureter or kidney, and 37 (80.4%) having osteoporosis. Patients were divided into SH and non-SH groups based on postoperative serum calcium levels. Preoperative biochemical indicators, bone turnover markers, and renal function parameters were analyzed and correlated with postoperative SH. RESULTS: Statistically significant (P < 0.05) differences were found in preoperative serum calcium (serum Ca), intact parathyroid hormone, serum phosphorus (serum P), serum Ca/P, percentage decrease of serum Ca, total procollagen type 1 intact N-terminal propeptide, osteocalcin (OC), and alkaline phosphatase levels between the two groups. Multivariate analysis showed that serum P (odds ratio [OR] = 0.989; 95% confidence interval [95% CI] = 0.981-0.996; P = 0.003), serum Ca (OR = 0.007; 95% CI = 0.001-0.415; P = 0.017), serum Ca/P (OR = 0.135; 95% CI = 0.019-0.947; P = 0.044) and OC levels (OR = 1.012; 95% CI = 1.001-1.024; P = 0.036) were predictors of early postoperative SH. The receiver operating characteristic curve analysis revealed that serum P (area under the curve [AUC] = 0.859, P < 0.001), serum Ca/P (AUC = 0.735, P = 0.010) and OC (AUC = 0.729, P = 0.013) had high sensitivity and specificity. CONCLUSION: Preoperative serum P, serum Ca/P and osteocalcin levels may identify patients with PHPT at risk for early postoperative SH after PTX.

Turning Points in Cross-Disciplinary Perspective of Primary Hyperparathyroidism and Pancreas Involvements: Hypercalcemia-Induced Pancreatitis, MEN1 Gene-Related Tumors, and Insulin Resistance.

We aimed to provide an in-depth analysis with respect to three turning points in pancreas involvement in primary hyperparathyroidism (PHP): hypercalcemia-induced pancreatitis (HCa-P), MEN1 (multiple endocrine neoplasia)-related neuroendocrine tumors (NETs), and insulin resistance (IR). This was a comprehensive review conducted via a PubMed search between January 2020 and January 2024. HCa-P (n = 9 studies, N = 1375) involved as a starting point parathyroid NETs (n = 7) or pancreatitis (n = 2, N = 167). Case report-focused analysis (N = 27) showed five cases of pregnancy PHP-HCa-P and three reports of parathyroid carcinoma (female/male ratio of 2/1, ages of 34 in women, men of 56). MEN1-NET studies (n = 7) included MEN1-related insulinomas (n = 2) or MEN1-associated PHP (n = 2) or analyses of genetic profile (n = 3), for a total of 877 MEN1 subjects. In MEN1 insulinomas (N = 77), the rate of associated PHP was 78%. Recurrence after parathyroidectomy (N = 585 with PHP) was higher after less-than-subtotal versus subtotal parathyroidectomy (68% versus 45%, p < 0.001); re-do surgery was 26% depending on surgery for pancreatic NETs (found in 82% of PHP patients). MEN1 pathogenic variants in exon 10 represented an independent risk factor for PHP recurrence. A single pediatric study in MEN1 (N = 80) revealed the following: a PHP rate of 80% and pancreatic NET rate of 35% and 35 underlying germline MEN1 pathogenic variants (and 3/35 of them were newly detected). The co-occurrence of genetic anomalies included the following: CDC73 gene variant, glucokinase regulatory protein gene pathogenic variant (c.151C>T, p.Arg51*), and CAH-X syndrome. IR/metabolic feature-focused analysis identified (n = 10, N = 1010) a heterogeneous spectrum: approximately one-third of adults might have had prediabetes, almost half displayed some level of IR as reflected by HOMA-IR > 2.6, and serum calcium was positively correlated with HOMA-IR. Vitamin D deficiency was associated with a higher rate of metabolic syndrome (n = 1). Normocalcemic and mildly symptomatic hyperparathyroidism (n = 6, N = 193) was associated with a higher fasting glucose and some improvement after parathyroidectomy. This multilayer pancreas/parathyroid analysis highlighted a complex panel of connections from pathogenic factors, including biochemical, molecular, genetic, and metabolic factors, to a clinical multidisciplinary panel.

Risk of Malignant Neoplasm in Patients with Primary Hyperparathyroidism: A Systematic Review and Meta-analysis.

This study aimed to evaluate the prevalence and risk of malignant neoplasm in primary hyperparathyroidism (PHPT) patients. Potentially eligible studies were retrieved from PubMed and Embase databases from inception to November 2023 using search strategy consisting of terms for "Primary hyperparathyroidism" and "Malignant neoplasm". Eligible study must report prevalence of malignant neoplasm among patients with PHPT or compare the risk of malignant neoplasm between patients with PHPT and comparators. Point estimates with standard errors were extracted from each study and combined using the generic inverse variance method.A total of 11,926 articles were identified. After two rounds of systematic review, 50 studies were included. The meta-analysis revealed that pooled prevalence rates of overall cancer was 0.19 (95%CI: 0.13-0.25; I2 94%). The two most prevalent types of malignancy among patients with PHPT ware papillary thyroid cancer (pooled prevalence: 0.07; 95%CI: 0.06-0.08; I2 85%) and breast cancer (pooled prevalence: 0.05; 95%CI: 0.03-0.07; I2 87%). Subgroup analysis of studies focusing on patients undergoing parathyroidectomy reported a fourfold higher prevalence of papillary thyroid cancer than the remaining studies (0.08 versus 0.02). The meta-analysis of cohort studies found a significant association between PHPT and overall cancer with the pooled risk ratio of 1.28 (95%CI: 1.23-1.33; I2 66.9%).We found that the pooled prevalence of malignant neoplasm in PHPT was 19%, with papillary thyroid cancer and breast cancer being the most prevalent types. The meta-analysis of cohort studies showed that patient with PHPT carried an approximately 28% increased risk of malignancy.

Results of a novel intervention to increase rates of diagnosis and treatment of primary hyperparathyroidism.

BACKGROUND: Veterans with primary hyperparathyroidism are under diagnosed and undertreated. We report the results of a pilot study to address this problem. METHODS: We implemented a stakeholder-driven, multi-component intervention to increase rates of diagnosis and treatment for primary hyperparathyroidism at a single VA hospital. Intervention effects were evaluated using an interrupted time series analysis. RESULTS: The mean age of Veterans affected by the intervention was 67 years (SD 12.1) and 84 â€‹% were men. Compared to the pre-intervention period, the intervention doubled the proportion of Veterans who were appropriately evaluated for hyperparathyroidism (absolute difference 25 â€‹%, 95 â€‹% CI 11 â€‹%-38 â€‹%, p â€‹< â€‹0.001) and increased referrals for treatment by 27 â€‹% (95 â€‹% CI 7 â€‹%-47 â€‹%, p â€‹< â€‹0.012). CONCLUSION: Our pilot study suggests it is feasible to address the underdiagnosis and undertreatment of primary hyperparathyroidism among Veterans.

Variable presentation and outcomes of primary hyperparathyroidism in children and adolescents.

OBJECTIVES: Primary hyperparathyroidism (PHPT) in paediatric and adolescent age group presents with some unique challenges for clinicians. While the disease in the adult counterparts presents with symptoms which are described quite extensively in literature, children/adolescents have manifestations which are quite different and severe compared to the former. The present case series aimed to highlight the peculiarities of presentation of PHPT in children and adolescents. CASE PRESENTATION: In this case series, we present experience of 5 cases of PHPT in children and adolescents from our centre. We compared our data with the data already available in literature. We have also described salient presenting features of PHPT in individuals less than 19 years old previously reported in literature and pointed out the specificities of this disease at this age group. CONCLUSIONS: PHPT in children and adolescents should be considered as a separate entity compared to that in adults, given its unique features, such as rachitic features, and severity of different presenting phenotypes. Persistence of rachitic features despite vitamin D correction, pancreatitis, bilateral nephrolithiasis and otherwise unexplained psychiatric abnormalities of insidious onset require greater clinical vigilance and serum/urine calcium testing to rule out this uncommon yet possible entity.

Association between primary hyperparathyroidism and cardiovascular outcomes: A systematic review and meta-analysis.

BACKGROUND: Excess parathyroid hormone (PTH) is associated with an increased risk of cardiovascular disease (CVD). PURPOSE: We aimed to evaluate the correlation between primary hyperparathyroidism (PHPT) and CVD or cardiovascular (CV) death. DATA SOURCES: Comprehensive searches of PubMed, Embase and ClinicalTrials.gov until May 20, 2023 with the following keywords: "primary hyperparathyroidism," "cardiovascular disease," and "mortality." STUDY SELECTIONS: Cohort studies and randomized controlled trials comparing PHPT patients to the general population and those who had received parathyroidectomy (PTX) to those who did not. DATA EXTRACTION: Three investigators independently extracted data and assessed study quality. DATA SYNTHESIS: Eleven cohort studies and one randomized controlled trial were identified, including 264,227 PHPT patients with or without PTX, and the average age reported in the studies was 62 years. PHPT was associated with a higher risk of total death (RR 1.39 [95 % confidence interval (CI) 1.23-1.57) and CV death (RR 1.61 [95 % CI 1.47-1.78]) than the general population. However, there was no significant difference in CVD risk between patients with PHPT and the general population (RR 1.73 [95 % CI 0.87-3.47]). When compared to patients without PTX, PTX had a lower risk of CV death (RR 0.75 [95 % CI 0.71-0.80]), total death (RR 0.64 [95 % CI 0.60-0.70]) and CVD (RR 0.92 [95 % CI 0.90-0.94]). LIMITATION: High heterogeneity among the included articles, and most of them were retrospective and older studies. CONCLUSIONS: PHPT was associated with higher risk of total death and CV death while PTX was associated with lower risk of total death, CV death, and CVD.

Actigraphy measures show sleep improvement after parathyroidectomy for primary hyperparathyroidism.

IMPORTANCE: The symptoms of primary hyperparathyroidism are often subtle, such as fatigue, mood changes, and sleep disturbances. After parathyroidectomy, patients often report improvement in sleep and mood; however, objective data supporting these improvements is lacking. OBJECTIVE: This prospective study uses standard measures to objectively and subjectively assess sleep in patients with primary hyperparathyroidism before and after parathyroidectomy. DESIGN: A longitudinal prospective study was conducted over three one-week-long periods: pre-parathyroidectomy, 1-week post-parathyroidectomy, and three months post-parathyroidectomy. During each time point, patients wore an actigraphy device, recorded a sleep diary, and completed the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), and Depression Anxiety Stress Scale (DASS). Statistical analysis was performed using repeated measures models to compare the average measures among the three time points and test for trends over time. SETTING: Single institution, tertiary care center. PARTICIPANTS: Patients with primary hyperparathyroidism from ages 18 to 89 years old. EXPOSURE: Parathyroidectomy between September 2020 and January 2024. MAIN OUTCOMES AND MEASURES: Actigraphy data, consensus sleep diary, Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Depression Anxiety Stress Scales - 21 Items (DASS). RESULTS: Thirty-six patients were enrolled, and 34 patients completed the study. Actigraphy data showed a significant negative trend in average sleep latency (p = 0.045) and average time in bed (p = 0.046). Sleep diary data showed additional differences in the number of awakenings (p = 0.002), wake after sleep onset (p < 0.001), sleep quality (p < 0.001), and sleep efficiency (p = 0.02) among the three time points and/or as a significant negative trend. PSQI and ISI scores were significantly different among the three time points (p = 0.002 and p < 0.001, respectively) and also declined significantly over time (p = 0.008 and p = 0.007, respectively). DASS depression, anxiety, and stress scores were significantly different among the three time points (p < 0.001, p = 0.01, and p < 0.001, respectively), and stress also declined significantly over time (p = 0.005). CONCLUSION AND RELEVANCE: This study represents the most extensive prospective study demonstrating objective and subjective sleep and mood improvement in patients with primary hyperparathyroidism after parathyroidectomy.

Acute pancreatitis associated with primary hyperparathyroidism during pregnancy.

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Primary hyperparathyroidism in pregnancy: a case report highlighting uncommon complication.

Primary hyperparathyroidism (PHPT) is characterized by elevated levels of calcium and parathyroid hormone (PTH). However, the interpretation of diagnostic tests, such as serum calcium and PTH levels, is complex in pregnant women. The aim of this report is to present a case of PHTP in a pregnant adolescent, with a special emphasis on an uncommon complication, as well as diagnostic and treatment strategies. A 17-year-old pregnant female presented with hyperemesis gravidarum and neurological symptoms, leading to the diagnosis of cerebral venous thrombosis. Further investigations revealed hypercalcemia and persistently elevated PTH levels, consistent with PHPT. After localization studies, the patient underwent an emergency parathyroidectomy with a diagnosis of parathyroid adenoma. During follow-up, intrauterine growth restriction and severe preeclampsia developed, necessitating an emergency cesarean section. Both the mother and neonate had favorable outcomes. PHPT is an infrequent condition in the pregnant population, and its diagnosis can be challenging due to the overlap of symptoms with normal physiological changes during pregnancy. The occurrence of uncommon complications, such as thrombotic phenomena, highlights the need for a comprehensive approach to ensure early detection and management. In most cases, parathyroidectomy is the treatment of choice.

El hiperparatiroidismo primario (HPTP) se caracteriza por niveles elevados de calcio y hormona paratiroidea (PTH). Sin embargo, la interpretación de pruebas diagnósticas, como los niveles de calcio sérico y PTH, es compleja en mujeres embarazadas. El objetivo de este reporte es presentar un caso de HPTP en una adolescente embarazada, con especial hincapié en una complicación infrecuente, así como en las estrategias diagnósticas y de tratamiento. Una mujer embarazada de 17 años presentó hiperémesis gravídica y síntomas neurológicos, lo que llevó al diagnóstico de trombosis venosa cerebral. Posteriores investigaciones revelaron hipercalcemia y niveles persistentemente elevados de PTH, consistentes con HPTP. Tras la realización de estudios de localización, la paciente fue sometida a una paratiroidectomía de emergencia con diagnóstico de adenoma de paratiroides. Durante el seguimiento, se desarrolló restricción del crecimiento intrauterino y preeclampsia grave, lo que resultó en la necesidad de realizar una cesárea de emergencia. Tanto la madre como el neonato evolucionaron favorablemente. El HPTP es una condición infrecuente en la población embarazada y su diagnóstico puede ser desafiante por la superposición de síntomas con los cambios fisiológicos normales del embarazo. La aparición de complicaciones infrecuentes, como fenómenos trombóticos, resalta la necesidad de un abordaje integral para garantizar la detección y el manejo temprano. En la mayoría de los casos, la paratiroidectomía es el tratamiento de elección.

[Association between preoperative cholecalciferol therapy and hypocalcemia after parathyroidectomy in patients with primary hyperparathyroidism].

BACKGROUND: Primary hyperparathyroidism (PHPT) is a endocrine disorder characterized by excessive secretion of parathyroid hormone (PTH) from parathyroid gland tumors. Parathyroidectomy (PTE) is the main treatment for PHPT, but it can lead to hypocalcemia in up to 46% of cases. Hypocalcemia is associated with seizures and life-threatening cardiac arrhythmias, and vitamin D deficiency can exacerbate PHPT severity and contribute to «hungry bones syndrome,¼ resulting in severe and persistent postoperative hypocalcemia. AIM: To evaluate the association and determine the strength of the relationship between preoperative cholecalciferol therapy and the occurrence of hypocalcemia within 1-3 days after PTE in patients with PHPT. MATERIALS AND METHODS: The study was conducted at the Endocrinology Research Centre, during the periods of 1993-2010 and 2017-2020. The inclusion criteria consisted of patients diagnosed with PHPT who required PTE, had a serum 25-hydroxyvitamin D (25(OH)D) level below 20 ng/mL, and a serum total calcium level below 3 mmol/L. The exclusion criterion was the use of medications that affect calcium-phosphorus metabolism, including cinacalcet, denosumab, or bisphosphonates, either as monotherapy or as part of combination therapy. RESULTS: There were 117 patients, including 110 (94%) females and 7 (6%) males. The median age and interquartile range were 58 [49; 65] years. Among the participants, 21 (18%) received cholecalciferol supplementation for a duration of 2 weeks to 2 months prior to PTE, aiming to address vitamin D deficiency. The remaining 96 (82%) participants did not receive -cholecalciferol supplementation. Both groups, i.e., participants receiving cholecalciferol and those who did not, were similar in terms of anthropometric factors (sex and age at the time of surgery), preoperative clinical characteristics (BMD decrease), and laboratory parameters (PTH, total calcium, phosphorus, ALP, OC, CTX-1, and 25(OH)D levels). The occurrence of postoperative hypocalcemia was significantly lower in participants who received cholecalciferol supplementation (10% vs. 63%, p<0,001, FET2). Cholecalciferol intake showed a negative association with hypocalcemia development (RR=0,15, 95% CI (0,03; 0,51)). CONCLUSION: Preoperative cholecalciferol supplementation for 2 weeks to 2 months before PTE reduces the risk of postoperative hypocalcemia in patients with PHPT by 2-33 times.