Influence of Iodine Deficiency and Excess on Thyroid Function Tests

Case Report of Graves' Disease in a 45-Year-Old Woman Secondary to Herceptin Treatment for Breast Cancer

Graves' disease is the most common cause of thyrotoxicosis and is characterized by ophthalmopathy with proptosis, chemosis, or conjunctival injection; pretibial myxedema; and thyroid acropachy. It is an autoimmune disease that can be genetic or influenced by coexisting environmental factors such as exposure to anticancer drugs, including immune checkpoint inhibitors. The incidence rate of breast cancer is increasing due to rising awareness of risk factors and screening for breast cancer, and the mortality rate is decreasing due to recent advances in cancer treatment. However, there are side effects that are attributed to these treatment modalities, manifesting in various forms in breast cancer survivors, which are reflected in the patient in this case study.

Improving Iodine Intake in Rural Haiti through Social Enterprise: A Cross-Sectional Study in the Central Plateau

Iodine intake in Haiti has increased in recent years thanks to the "Bon Sel" social enterprise approach to salt fortification and distribution by the market segment. However, it was uncertain whether this salt reached remote communities. This cross-sectional study aimed to assess the iodine status of school-age children (SAC) and women of reproductive age (WRA) in a remote region of the Central Plateau. A total of 400 children (9-13 years) and 322 women (18-44 years) were recruited through schools and churches, respectively. Urinary iodine (UIC) and urinary creatinine (UCC) concentrations were measured in spot samples, and thyroglobulin (Tg) on dried blood spots. Their iodine intake was estimated, and dietary information collected. The median (IQR) UIC in SAC was 130 µg/L (79-204, n = 399), and in WRA, 115 µg/L (73-173, n = 322). The median (IQR) Tg in SAC was 19.7 µg/L (14.0-27.6, n = 370), and in WRA, 12.2 µg/L (7.9-19.0, n = 183); 10% of SAC had Tg > 40 µg/L. Estimated iodine intake was 77 µg/day and 202 µg/day in SAC and WRA, respectively. Iodized table salt was rarely consumed, though bouillon was used daily; this is hypothesized to be a major contributor to dietary iodine intake. Iodine intake in this remote region seems to have improved considerably since the 2018 national survey, though SAC remain at risk. These results point to the potential effectiveness of using social business principles to deliver humanitarian solutions.

The Influence of Iron Depletion and Chronic Energy Deficiency on the Risk of Hypothyroidism in Pregnant Women Living in Iodine Deficiency Disorders Endemic Areas in Badegan Ponorogo District East Java, Indonesia

Several minerals are needed for thyroid hormone to work properly, such as iodine and iron. Iron is one of important essential trace elements that serves as co-factor for thyroid peroxidase (TPO). Those with iron deficiency have lower ferritin serum level than those who are normal. In particular, pregnant women with chronic energy deficiency (CED) have higher anemia risk than the otherwise. The study aimed to measure ferritin level, CED and hypothyroidism among pregnant women living in iodine deficiency disorders (IDD) endemic areas. A total of 37 pregnant women aged 18-45 y-oldwith pregnancy of 2 to 8 mo living in ID Dendemic of Dayakan and Watu Bonang Villages of Ponorogo District were include dinthestudy. Two different measurements were taken namely, anthropometric measurement of mid-upper arm circumference (MUAC) or upper circumference (UAC) which is more correct term to use, and blood markers of iodine and iron status were assessed using thyroid stimulating hormone (TSH), free thyroxine (fT4), and bloodferritin. Among pregnant women, 27% had hypothyroidism and 54.05% had iron depletion, with 30% had both conditions. The hypothyroidism was higher in pregnant women had CED than those non-CED, 50% vs. 18.5%. No significant correlation (p≥0.05) between hypothyroidism and both ferritin and CED, but adjusted odds ratio (AOR) was found at 7.7 (95% CI: 1.2-52.9), indicated more than four times higher risk of hypothyroidism in pregnant women with CED than the otherwise. Hypothyroidism in pregnant women living in Ponorogo was not caused by iron deficiency, but allegedly by lack of other nutritional intake. Conclusion: Integrated and sustainable efforts to improve nutritional status is needed since pre-conception and throughout pregnancy.

Experimental and theoretical studies on halide binding with a p-xylyl-based azamacrocycle

A p-xylyl-based macrocycle L has been synthesized and its binding properties with halides have been investigated by (1)H NMR titrations, single crystal X-ray diffraction analysis, and density functional theory (DFT) calculations. As investigated by (1)H NMR titrations, the ligand preferentially binds a halide in a 1:2 binding mode, with the association constants (in log K2) of 2.82, 2.70, 2.28, and 2.20 for fluoride, chloride, bromide, and iodide, respectively. The overall binding trend was found to be in the order of fluoride > chloride > bromide > iodide, reflecting that the binding strength correlates with the relative basicity and size of the respective halide. Crystallographic studies indicate that the ligand forms 1:2 complexes with chloride, bromide and iodide. In the chloride complex, the ligand is hexaprotonated and each chloride is held via three NH···Cl(-) bonds. The ligand is tetraprotonated for the other complexes, where each halide is H-bonded to two secondary ammonium NH(+) groups via NH···X(-) bonds. The results of DFT calculations performed on [H6L](6+) at M062x/6-311G (d,p) level in both gas and solvent phases, suggest that the ligand binds halides with the binding energy in the order of F(-) > Cl(-) > Br(-) > I(-), supporting the experimental data obtained from (1)H NMR studies. Results from DFT calculations further indicate that a 1:2 binding is energetically more favorable than a 1:1 binding of the ligand.

Biomarkers of nutrition for development--iodine review

The objective of the Biomarkers of Nutrition for Development (BOND) project is to provide state-of-the-art information and service with regard to selection, use, and interpretation of biomarkers of nutrient exposure, status, function, and effect. Specifically, the BOND project seeks to develop consensus on accurate assessment methodologies that are applicable to researchers (laboratory/clinical/surveillance), clinicians, programmers, and policy makers (data consumers). The BOND project is also intended to develop targeted research agendas to support the discovery and development of biomarkers through improved understanding of nutrient biology within relevant biologic systems. In phase I of the BOND project, 6 nutrients (iodine, vitamin A, iron, zinc, folate, and vitamin B-12) were selected for their high public health importance because they typify the challenges faced by users in the selection, use, and interpretation of biomarkers. For each nutrient, an expert panel was constituted and charged with the development of a comprehensive review covering the respective nutrient's biology, existing biomarkers, and specific issues of use with particular reference to the needs of the individual user groups. In addition to the publication of these reviews, materials from each will be extracted to support the BOND interactive Web site (http://www.nichd.nih.gov/global_nutrition/programs/bond/pages/index.aspx). This review represents the first in the series of reviews and covers all relevant aspects of iodine biology and biomarkers. The article is organized to provide the reader with a full appreciation of iodine's background history as a public health issue, its biology, and an overview of available biomarkers and specific considerations for the use and interpretation of iodine biomarkers across a range of clinical and population-based uses. The review also includes a detailed research agenda to address priority gaps in our understanding of iodine biology and assessment.

Assessment of iodine nutrition in populations: past, present, and future

Iodine status has been historically assessed by palpation of the thyroid and reported as goiter rates. Goiter is a functional biomarker that can be applied to both individuals and populations, but it is subjective. Iodine status is now assessed using an objective biomarker of exposure, i.e., urinary iodine concentrations (UICs) in spot samples and comparison of the median UIC to UIC cut-offs to categorize population status. This has improved standardization, but inappropriate use of the crude proportion of UICs below the cut-off level of 100 µg/L to estimate the number of iodine-deficient children has led to an overestimation of the prevalence of iodine deficiency. In this review, a new approach is proposed in which UIC data are extrapolated to iodine intakes, adjusted for intraindividual variation, and then interpreted using the estimated average requirement cut-point model. This may allow national programs to define the prevalence of iodine deficiency in the population and to quantify the necessary increase in iodine intakes to ensure sufficiency. In addition, thyroglobulin can be measured on dried blood spots to provide an additional sensitive functional biomarker of iodine status.

Neonatal plasma TSH--estimated upper reference intervals for diagnosis and follow up of congenital hypothyroidism

Age- and method-dependent plasma TSH reference intervals are essential for the diagnosis and management of congenital hypothyroidism. However, accurate reference intervals for plasma TSH have not been adequately defined due to the difficulties in obtaining samples from a healthy paediatric population. To overcome the difficulties in generating such intervals we estimated method-dependent plasma TSH upper-reference intervals by determining the blood spot TSH upper-reference interval from newborn blood spot TSH screening data (N = 10,697) and then derived method-dependent conversion factors for blood spot TSH to plasma TSH concentration from paired-blood spot and plasma TSH measurements. The upper reference interval for blood spot TSH of 3.04 mU/L was obtained from the 97.5th centile of the selected data. Using experimentally-derived conversion factors, estimates of plasma TSH upper reference intervals of 7.6, 6.3, 7.3, 8.3 and 6.5 mU/L were obtained for the Siemens Centaur, Abbott Architect, Roche Elecsys E170, Siemens Immulite 2000 and Beckman access HYPERsensitive TSH assays respectively. These estimated method-dependent plasma TSH upper reference intervals will be of great practical use to clinicians to diagnose and to follow up infants found to have increased blood spot TSH concentrations identified by Newborn Screening programmes.