Monitoring Iodine Deficiency Research Articles

Information Registry System on Congenital Hypothyroidism: A Systematic Review

Background: Congenital hypothyroidism is the most common congenital disorder of the endocrine system, leading to preventable mental retardation. Objectives: We aimed to evaluate the current status of congenital hypothyroidism information registry systems. Methods: In this systematic review 290 papers identified. A total of 254 articles were screened, of which 17 qualified articles were selected through the databases of Scopus, science direct ProQuest, PubMed, as well as the search engine Google scholar (no restriction on date of publication) up to 2020, were searched. Inclusion criteria were the Articles with the English language that examining information registry systems on congenital hypothyroidism. Articles whose full texts were not accessible, case reports, and letters to the editor had to be excluded. Results: This study showed that the primary goal of nearly half (50%) of the information registry systems for congenital hypothyroidism is to evaluate the efficiency and effectiveness of the screening program. Other information registry systems for congenital hypothyroidism have examined the epidemiology of the disease in 4 studies (23.6%), monitoring iodine deficiency in 3 studies (18%), surveillance disease in 1 study (6%), and describing the clinical and familial features of the patient in 1 study (6%). Conclusions: Few studies have been done on developing information registry systems, and most studies have focused on the use of information systems in this field. Further comprehensive reviews are recommended to investigate the infrastructure of the commission national registry and world network to record information units on congenital hypothyroidism.

Monitoring Iodine Deficiency in a District Hospital, Nepal

Background Iodine deficiency possesses serious threat to pregnant women and infants. During pregnancy, iodine deficiency can result in stillbirth while in infants it can lead to impaired brain development. Objective This study was conducted to assess the status of iodine deficiency among pregnant women and infants. Method Ninety seven pregnant women seeking antenatal check-up (ANC) from Chautara Hospital Sindhupalchowk were included to analyze urine iodine. Thirty one mothers and their children were followed-up for their clinical status. Additionally, the infants were assessed for their urine iodine excretion and the mothers were assessed for their awareness about iodine and iodine deficiency disorder (IDD). Result Urinary iodine excretion revealed 25.2% of pregnant women and 20% children below one year of age had insufficient iodine intake while 42.9% of pregnant women and 24% children had iodine level above normal. Almost all households were found using iodized salt, 80% respondents had heard about iodized salt, 13% mothers were aware of benefits of iodized salt, 41.9% had knowledge of iodine deficiency diseases and 38.4% cognized the source of iodine. Conclusion Though awareness about iodine and iodine deficiency disorder was satisfactory, pregnant women and children were at risk of iodine deficiency and excessive iodine disorder. Therefore, to improve health of pregnant women and newborn, their nutrition must be prioritized which ultimately will help reduce morbidity and mortality.

Assessment of indicators of medical and biological monitoring of iodine deficiency diseases

The problem of iodine deficiency remains relevant all over the world due to the widespread prevalence and the negative impact it has on human health in all agegroups. Iodine deficiency leads to a decrease in the intellectual potential of children, the development of reproductive disorders at a young age, as well as the formation of multinodular toxic goiter as the last stage of goiter transformation, accompanied by heart rhythm disturbances in middle and old age. The article covers the issues of monitoring iodine deficiency in the regions of Russia and provides data on the situation in the world on the development of future prevention programs and current prevention programs. A detailed analysis of each criterion for the severity of iodine deficiency and the effectiveness of preventive programs was carried out. Particular attention is paid to the criterion of neonatal hyperthyrotropinemia as a promising indicator for monitoring iodine deficiency.

Synthesis and characterization of new tyrosine capped anisotropic silver nanoparticles and their exploitation for the selective determination of iodide ions

The assessment of the iodine status of natural waters is crucial for focusing future strategies for controlling and monitoring iodine deficiency disorders (IDD). Nanoparticles have been increasingly used as sensors for several organic and inorganic analytes. In this study, we report the synthesis of new Tyrosine Capped Anisotropic Silver Nanoparticles (AgNPs). The AgNPs were characterized by TEM, UV–vis spectroscopy, and polarized and depolarized dynamic light scattering measurements, and were used for the quantitative determination of iodide ions in the presence of excess chloride ions. Both anions gave rise to an etching of the tips of the nanoprims converting them in rounded nanoplates. However, iodide ions perform this etching much better than chloride ones, allowing for their selective determination in tap waters. Fluoride and bromide anions give rise to a more efficient etching than chloride ions, but their presence does not interfere with iodide determination. This method was also used to determine the concentration of iodide in a sample of drinking water.

Larger Thyroid Volume and Adequate Iodine Nutrition in Chinese Schoolchildren: Local Normative Reference Values Compared with WHO/IGN.

Objective. Thyroid volume measured by ultrasound to define goiter needs reliable local thyroid volume reference from iodine-sufficient populations. The aim of this study is to explore the reference interval for normal thyroid volume in schoolchildren aged 8–10 years from Zhejiang Province, China. Methods. A probability-proportionate-to-size sampling method was applied to select a representative sample of 1213 children aged 8–10 years in Zhejiang Province to detect the thyroid volume, salt iodine, and urine iodine. Results. Median urinary iodine concentration in involved schoolchildren was 178.30 (125.00) μg l−1, with the percentage of samples less than 100 μg l−1 as 12.69% and more than 300 μg l−1 as 15.25%. Thyroid volume was significantly correlated with age and anthropometric measurements independently of each other. The 97th percentile of thyroid volume in our study was larger generally than the new international reference. Conclusions. The iodine nutritional status in Zhejiang Province was at an adequate level. Despite some limitations in this study, we initially established the reference values for thyroid volume in 8–10-year-old schoolchildren in Zhejiang Province, China, as a local reference to be used for monitoring iodine deficiency disorders.

Maternal–Fetal Thyroid Function at the Time of Birth and Its Relation with Iodine Intake

The effects of moderate variations in dietary iodine intake on maternal and fetal thyroid function are poorly understood. Recent studies question the usefulness of neonatal screening of congenital hypothyroidism as a tool for monitoring iodine deficiency. We proposed to test the hypothesis of an association between iodine intake during the last trimester of pregnancy and fetal thyroid function at the time of birth. The study was undertaken at term in 233 healthy pregnant women (29.7±5.6 years) and in their newborn. Inclusion of women in the study was done within the 24 hours before delivery. The median maternal urinary iodine concentration was 126.5 μg/L. The maternal free triiodothyronine (FT3), although not thyrotropin (TSH) and free thyroxine (FT4), correlated significantly with the urinary iodine concentration (r=0.17, p=0.013). The cord blood TSH, FT4, and FT3 correlated positively with the maternal urinary iodine concentration at the time of delivery (r=0.24, p=0.001; r=0.16, p=0.032; and r=0.24, p=0.003, respectively). The cord blood and heel blood TSH correlated positively with the amniotic fluid iodine concentration (r=0.21, p=0.015 and r=0.15, p=0.036). The cord blood TSH correlated positively with the cord blood FT4 (r=0.21, p=0.022) and FT3 (r=0.32, p=0.017). The maternal TSH correlated significantly with the cord blood TSH (r=0.22, p=0.014) and with the heel blood TSH (r=0.13, p=0.050). The results of this study show the presence of a positive association of TSH-FT4 at the time of delivery, which may be modulated by the amount of iodine consumed by the mother during pregnancy.

Determination of Thyroid Volume by Ultrasonography among Schoolchildren in Philippines

Objective. Iodine deficiency is defined by the goiter and the urinary iodine concentration. However, a lack of local thyroid volume reference data resulted in the vague definition of goiter, especially in school-aged children. The aim of this paper was to determine the thyroid volumes by ultrasonography in schoolchildren aged 6 to 12 years living in Cagayan areas in Philippine. Methods. Cross-sectional thyroid ultrasonographic data of 158 schoolchildren aged 6–12 years from Tuguegarao and Lagum in Cagayan valley, Philippine were used. Thyroid volumes were compared based on logistic issue and urban and rural area and compared with other previously reported data. Results. The mean values of thyroid volume in Tuguerago and Lagum were 2.99 ± 1.34 mL and 2.42 ± 0.92 mL. The thyroid size was significantly in association with age (P < 0.00), weight (P < 0.00), height (P < 0.00), and BSA (P < 0.00) by Pearson's correlation. The median thyroid volumes of schoolchildren investigated in this study were generally low compared to international reference data by age group but not by BSA. Conclusions. We propose for the first time local reference ultrasound values for thyroid volumes in 6–12 aged schoolchildren that should be used for monitoring iodine deficiency disorders.

Neonatal TSH screening: is it a sensitive and reliable tool for monitoring iodine status in populations?

Iodine deficiency is the most common cause of preventable brain damage in the newborn. The indicators for assessing iodine nutritional status include urinary iodine excretion, thyroid size, thyroid stimulating hormone (TSH) and thyroglobulin (Tg) concentrations in the blood. Neonatal TSH concentration is increased when the supply of thyroid hormone and iodine from the maternal circulation to the foetus has been compromised. The World Health Organization (WHO) has suggested that when a sensitive assay is used on samples collected 3-4 days after birth, a <3% frequency of TSH concentrations >5 mIUl(-1) indicates iodine sufficiency in a population. However, many studies have attempted to apply the frequency of neonatal TSH values >5 mIUl(-1) in determining population iodine status and monitoring intervention programmes, and although some have proven to be successful, most have provided conflicting or uncertain data. This is due to the many technical issues that remain unresolved on the use of neonatal TSH screening for monitoring iodine status, making it doubtful as a sensitive and reliable quantitative tool. More research is required to resolve these issues. In the interim, WHO should consider withdrawing its current guidelines for neonatal TSH screening for monitoring iodine deficiency in populations.

A challenge for monitoring iodine deficiency disorders in rural Nepal

Developing a strategy for monitoring iodine deficiency disorders (IDD) remains a big challenge in rural Nepal where great variations could exist in IDD status. To explore the possibility of variation in urinary iodine excretion (UIE) level in rural settings, we carried out a detailed study of UIE among 586 school children of 20 schools in five villages. Our data revealed statisitically significant differences in UIE values among rural villages and schools in the same villages. The policy-makers should keep such variations in mind for a successful monitoring of IDD in Nepal and other countries where such variations may exist.

A challenge for monitoring iodine deficiency disorders in rural Nepal

A challenge for monitoring iodine deficiency disorders in rural Nepal

Iodine nutrition in Sudan: Determination of thyroid-stimulating hormone in filter paper blood samples

Elnagar B, Gebre-Medhin M, Larsson A, Karlsson FA. Iodine nutrition in Sudan: determination of thyroid-stimulating hormone in filter paper blood samples. Scand J Clin Lab Invest 1997; 57: 175-182.In this study we examined the technique of measuring thyroid-stimulating hormone (TSH) on filter paper blood samples for use in evaluating the iodine nutrition status of newborns and adults living in iodine-deficient areas. Filter paper blood samples were obtained between the 5th and 7th day after birth from 103,43 and 103 term newborns living in Khartoum (mild iodine deficiency), Kosti (moderate iodine deficiency) and Darfur (severe iodine deficiency), respectively. TSH was measured with a commercial assay and the levels were compared with those obtained with the same method in 1147 samples from term Swedish newborns, obtained on the 3rd to the 5th day of life. The mean (95% confidence interval) TSH levels of the three Sudanese groups and the Swedish group were 7.1 (4.8-9.4), 8.3 (6.6-10.1), 11.9 (0.9-22.9) and 4.51 (3.8-5.3) mU 1−1, respectively. The mean TSH for all three Sudanese groups was higher than the Swedish mean (p<0.001).TSH levels determined in filter paper blood samples from adults living in an iodine-deficient area showed a correlation (p<0.001; r=0.55) to levels in corresponding serum samples (range 0.52-14.1 mU 1−1, median 3.4 mU 1−1). No significant correlation was found, however, between blood spot levels and serum levels within the reference range (<5 mU 1−1). A modification of the commercial procedure consisting in using three instead of two monoclonal antibodies did not sufficiently improve the assay for measurements of TSH within the reference range.Thus, there is a need to develop the filter paper technique further to make it a useful test for monitoring iodine deficiency in populations expected to have TSH levels close to the reference range. In the examination of neonates, however, with their birth-induced surge of TSH, the current assay promises to be a convenient tool for discovering iodine deficiency within a community.