Vitamin D levels and lipid profile in children and adolescents: a tight correlation.

INTRODUCTION: Vitamin D is an essential hormone for humans, playing an important role in musculoskeletal and calcium homeostasis. Its deficiency/insufficiency seems to contribute to the development of cardiometabolic diseases in adults: this correlation appears less clear for children and adolescents. The aim of this paper was to review literature data on the relationship between vitamin D and lipid profile alterations in pediatric population. EVIDENCE ACQUISITION: We carried out a comprehensive research in electronic databases, including MEDLINE and PubMed up to December 2022, for cross-sectional or prospective studies that investigated the correlation between serum vitamin D levels and lipid profile in children and adolescents. At the end of the process, 37 articles were included in this review. EVIDENCE SYNTHESIS: According to our findings, vitamin D deficiency/insufficiency is strongly associated with lower high-density lipoprotein (HDL) cholesterol levels and higher levels of triglycerides and total cholesterol. Data about low-density lipoproteins (LDL) cholesterol are inconsistent. The potential role of vitamin D supplements for the prevention of cardiometabolic disease currently remains a speculation. CONCLUSIONS: An increasing number of studies shows how hypovitaminosis D in the pediatric age may play a role in the pathogenesis of metabolic disorders and lipid profile alterations. Data regarding the potential role of vitamin D supplements for the prevention of cardiometabolic disease are currently controversial. Further studies are needed to evaluate the causality of this association and to assess the underlying pathogenetic mechanisms.

Changes in Urinary Iodine Levels Following Bariatric Surgery.

OBJECTIVE: Obesity has become an epidemic in the United States. Although bariatric surgery can effectively achieve weight loss by altering the gastrointestinal tract, it commonly results in micronutrient deficiency, requiring supplementation. Iodine is an essential micronutrient for the synthesis of thyroid hormones. We aimed to investigate changes in urinary iodine concentrations (UIC) in patients following bariatric surgery. METHODS: 85 adults who underwent either laparoscopic sleeve gastrectomy or laparoscopic Roux-en-Y gastric bypass surgery were enrolled. At baseline and 3 months after surgery, we evaluated spot UIC and serum thyroid stimulating hormone (TSH), vitamin D, vitamin B12, ferritin, and folate levels. Participants provided a 24-hour diet recall for iodine-rich foods and information about multivitamin use at each time point. RESULTS: There was a significant increase in median UIC (201 [120.0 - 288.5] vs 334.5 [236.3 - 740.3] µg/L; P < .001), a significant decrease in mean body mass index (44.0 ± 6.2 vs 35.8 ± 5.9; P < .001) and a significant decrease in TSH levels (1.5 [1.2 - 2.0] vs 1.1 [0.7 - 1.6] uIU/mL; P < .001) at 3 months postoperatively compared to baseline. Body mass index, UIC, and TSH levels before and after surgery did not differ based on the type of weight loss surgery. CONCLUSION: In an iodine-sufficient area, bariatric surgery does not cause iodine deficiency nor clinically significant changes in thyroid function. Different surgical procedures with different anatomical alterations in the gastrointestinal tract do not significantly affect iodine status.

Hypocalcemia During Lenvatinib Treatment for Advanced Thyroid Cancer: Clinical Features and Management in a Real-Life Setting.

Background: Several toxicities are recorded during treatment of advanced thyroid cancer (TC) with antiangiogenic drugs, including lenvatinib (LEN). Hypocalcemia was reported in registration studies, but little data are available from real-life cohorts. The aim of our study was to describe the incidence, characteristics, and the management of hypocalcemia in patients on LEN treatment. Methods: This is a retrospective cohort study of consecutive patients with advanced TC, treated with LEN for at least six months at a single tertiary center in Italy. Phosphocalcic metabolism was evaluated during treatment. Results: We included 25 patients treated for a mean of 29 ± 19 months (range 6-68 months). Hypocalcemia occurred in 6 of the 25 patients (24% [95% confidence interval 9.36-45.13%]), being of grade ≥3 in 2 of the 25 patients (8%), and recurrent in 4 of 6 patients (67%). The median time to hypocalcemia onset was 3 months (range 0.5-13 months) from starting LEN. No differences were found between patients who developed or not hypocalcemia regarding either starting/mean dose of LEN or clinicopathological characteristics. During the hypocalcemic crisis, the 2 patients with grade ≥3 hypocalcemia had low magnesium and low or inappropriately normal parathormone (PTH) levels, while 2 of 3 patients with grade 2 hypocalcemia had a secondary hyperparathyroidism. Hypocalcemia was managed with calcium oral supplementation in most cases, although up to 10% of patients required intravenous calcium treatment and transient LEN withdrawal. Conclusions: In this relatively small cohort, we observed an incidence of hypocalcemia of 24%, which is higher than that reported in the registration trial (6.9%). Both PTH-dependent and PTH-independent mechanisms explained hypocalcemia in the present cohort. Monitoring of serum calcium levels is strongly advised during the first year of LEN treatment, as hypocalcemia may be severe. More research is needed to confirm our findings and inform possible risk factors for hypocalcemia in advanced TC patients treated with LEN.

Lenvatinib-induced hypocalcaemia due to transient primary hypoparathyroidism.

CONTEXT: Radioiodine refractory differentiated thyroid cancer can be effectively treated with multi-tyrosine-kinase inhibitors (MKIs). Hypocalcaemia has been reported among the side effects of these drugs, but little is known about its pathophysiology and clinical relevance. CASE REPORT: We report the case of a 78-years-old woman with an aggressive papillary thyroid cancer infiltrating perithyroidal structures. The extent of surgery was limited to hemithyroidectomy, RAI treatment could not be performed, and she started lenvatinib treatment. After 4 months of therapy, the patient accessed the Emergency Department for a grade III hypocalcaemia (corrected serum calcium: 6.6 mg/dL, n.v. 8.1-10.4 mg/dL), due to primary hypoparathyroidism (serum PTH: 12.6 ng/L, n.v. 13-64 ng/L). The patient was treated with intravenous calcium infusions and vitamin D supplementation. After discharge, the oral dose of carbonate calcium (CaCO3) was of 6 g/day, and was titrated according to blood exams. Two weeks after discharge, while taking CaCO3 at the dose of 3 g/day, the patient experienced symptomatic grade II hypercalcemia (corrected serum calcium: 11.6 mg/dL), associated to the spontaneous reprise of PTH secretion, and leading to oral calcium withdrawal. During the subsequent follow-up, the patient remained eucalcemic without calcium supplementation. CONCLUSIONS: Though hypocalcaemia has been described as potential side effect of MKI treatment, this is the first report of a lenvatinib-induced primary hypoparathyroidism, in a patient with a documented normal parathyroid function after surgery. The periodical assessment of calcium-phosphorus metabolism is thus warranted to prevent this potentially lethal side effect, in both post-surgical hypoparathyroid and euparathyroid patients.

Post-Surgical Ablative or Adjuvant Radioiodine Therapy Has No Impact on Outcome in 1-4 cm Differentiated Thyroid Cancers without Extrathyroidal Extension.

Whether to conduct remnant ablation or adjuvant radioactive iodine (RAI) therapy in patients with intrathyroidal differentiated thyroid carcinoma (DTC), sized 1.1-4 cm, is debated. We evaluated the impact of RAI on outcome in this category of DTCs. We retrospectively enrolled 308 patients submitted to total thyroidectomy: 198 had tumors sized 1.1-2 cm (Group 1) and 110 of 2.1-4 cm (Group 2). Both groups were divided into patients receiving and not receiving RAI after surgery. RAI+ and RAI- patients did not significantly differ, regarding several clinical and pathological features. Final outcome was defined according to dynamic risk stratification. Remission was observed in the majority of Group 1 and Group 2 patients and outcome did not significantly differ between RAI+ and RAI- patients: respectively, 95.8% vs. 93.7% in Group 1, and 87.7% vs. 86.5% in Group 2. The majority of persistent cases, either RAI+ or RAI-, received therapeutic RAI administration, and about 50% of RAI- cases had an excellent response at final follow up, whereas no RAI+ persistent patients had a beneficial effect. Our findings demonstrate that patients with an intrathyroidal DTC sized 1.1-4 cm do not benefit from RAI. The outcome of these patients remains favorable, and the few patients with persistent diseases can be treated with RAI during follow up.

Iodine Supplementation in Women During Preconception, Pregnancy, and Lactation: Current Clinical Practice by U.S. Obstetricians and Midwives.

BACKGROUND: Iodine deficiency is a major public-health problem throughout the world, especially for pregnant women, and it is considered the most common cause of preventable intellectual impairment. In the United States, iodine status in pregnant women is considered mildly deficient. Therefore, the Endocrine Society, the American Thyroid Association, the Teratology Society, and the American Academy of Pediatrics recommend that women receive prenatal vitamins containing 150 µg of iodine daily during preconception, pregnancy, and lactation. The objectives of this study were to evaluate awareness of iodine nutrition among obstetricians and midwives in the United States, and to document current clinical practice regarding recommendations for iodine supplementation for women during preconception, pregnancy, and lactation. METHODS: All midwife members of the American College of Nurse-Midwives (ACNM) and all obstetrician members of the American Medical Association (AMA) were invited to participate in a web-based survey. RESULTS: A total of 199 midwives and 277 obstetricians participated in the survey. One third of both obstetricians and midwives considered iodine status in U.S. pregnant women to be deficient. Although almost all obstetricians and midwives would recommend prenatal multivitamins, most reported rarely or never recommending iodine-containing multivitamins for women planning pregnancy (68.7% and 70.2%, respectively), pregnant women (66% and 67.1%), or lactating women (68.7% and 71.7%). Of the respondents who did report prescribing iodine-containing supplements, 85% recommended supplementation during the first trimester and 75-80% during the second and third trimesters. However, of those who did recommend iodine supplementation, only 45% would prescribe the recommended 150 µg of iodine daily during pregnancy. Overall, 75% of U.S. obstetricians and midwives do not recommend or would recommend an inadequate amount of iodine during preconception, pregnancy, and lactation. CONCLUSIONS: Despite the important consequences of iodine deficiency for pregnant women and the recommendations of many medical societies, the majority of U.S. obstetricians and midwives who participated in this survey do not recommend iodine-containing vitamins in women planning pregnancy, during pregnancy, and during lactation.

Radioiodine ablation with 1,850 MBq in association with rhTSH in patients with differentiated thyroid cancer.

PURPOSE: The aim of this study was to evaluate the efficacy of post-operative radioiodine ablation with 1,850 MBq after recombinant human thyrotropin (rhTSH) administration in patients with differentiated thyroid carcinoma (DTC). We also aimed to assess the prognostic role of several patient features on the outcome of ablation. METHODS: We retrospectively analyzed data from a total of 125 patients with DTC who underwent post-operative radioiodine ablation with 1,850 MBq of ¹³¹I after preparation with rhTSH. One injection of 0.9 mg rhTSH was administered on each of two consecutive days; ¹³¹I therapy was delivered 24 h after the last injection, followed by a post-therapy whole-body scan. Successful ablation was assessed 6-12 months later and defined as an rhTSH-stimulated serum thyroglobulin (Tg) level ≤1.0 ng/ml and a normal neck ultrasound. RESULTS: Patients were stratified according to the American Thyroid Association (ATA) Management Guidelines for Differentiated Thyroid Cancer. Successful ablation was achieved in 82.4 % of patients, with an ablation rate of 95.1 % in low-risk patients and 76.2 % in intermediate-risk patients. Analyzing the correlation between ablation outcome and patient characteristics, we found a statistically significant association between failure to ablate and class of risk based on ATA guidelines (p = 0.025) and a stimulated Tg value at ablation of above 5 ng/ml (p < 0.001). CONCLUSION: The use of 1,850 MBq post-operative radioiodine thyroid remnant ablation in association with rhTSH is effective for low- and intermediate-risk patients. Moreover, in our study, we found a statistical correlation between failure to ablate and class of risk based on ATA guidelines for DTC and a stimulated Tg value at ablation.

Refining calcium test for the diagnosis of medullary thyroid cancer: cutoffs, procedures, and safety.

CONTEXT: Calcitonin (CT) measurement is crucial to the early diagnosis and the follow-up of medullary thyroid cancer (MTC). If the evaluation of stimulated CT levels is required, a provocative test can be performed, being the high-dose Ca test recently reintroduced in clinical practice. OBJECTIVE: Our objective was to identify gender-specific thresholds for MTC diagnosis in a large series of patients who underwent the Ca test. PATIENTS AND METHODS: A total of 91 patients (49 females and 42 males) underwent the Ca test (calcium gluconate, 25 mg/kg) before thyroidectomy and both basal CT (bCT) and stimulated CT (sCT) were compared with histological results by receiver operating characteristic plot analyses. To evaluate possible side effects of Ca administration, cardiac function has been extensively studied. RESULTS: bCT levels were found to harbor the same accuracy as sCT in the preoperative diagnosis of MTC. The best Ca thresholds for the identification of MTC were >26 and >68 for bCT and >79 and >544 pg/mL for sCT in females and males, respectively. The high tolerability and safety of the Ca test was demonstrated and advice offered to be followed before and during the test. CONCLUSIONS: Gender-specific bCT and sCT cutoffs for the identification of C-cell hyperplasia and/or MTC have been defined. The bCT and sCT were found to have a similar accuracy, indicating that serum CT assays with improved functional sensitivity may likely decrease the relevance of the stimulation test in several conditions. Finally, systematic cardiac monitoring confirms the safety of the Ca test.