The Impact of Iodine Status on the Recall Rate of the Screening Program for Congenital Hypothyroidism: Findings from Two National Studies in Iran

Background: Iodine deficiency is associated with goiter and impaired brain function. Neonatal thyroid-stimulating hormone (TSH) screening for congenital hypothyroidism used as an indicator of the degree of iodine deficiency and of its control. An increased frequency of thyroid-stimulating hormone (TSH) measurements above 5 mIU/L in newborn screening corresponds to the impaired iodine status of the population. The aim: to estimate the iodine deficiency and the effectiveness of iodine prophylaxis in Krasnoyarsk territory, Republics of Tuva and Khakassia according the results of neonatal TSH_screening. Methods: An 18-year analysis was performed in 34,980 newborns participating in the national thyroid newborn screening program. The TSH concentration was measured in dry blood spots collected by heel stick on filter paper, 96 hours after birth, using DELFIA method. Results: According to the data of the congenital hypothyroidism screening the rate of TSH < 5 mU/1 was 11.8% in Krasnoyarsk territory (23.9% in 2000) and corresponded to mild iodine deficiency. In different regions of Krasnoyarsk territory the rate of TSH < 5 mU/1 in the newborn varied from 3.5% to 23.7%. The highest values were marked in the Arctic peninsula Taimyr, in cities Zheleznogorsk (nuclear facility) and Sosnovoborsk, in Irbeysky, Suchobuzimsky, Eniseysky, Tuchtetsky, Novoselovsky regions (20.9–23.7%). In the Republic of Khakasia the rate of TSH < 5 mU/1 was 12.5%. In the Republic of Tyva the rate of TSH < 5 mU/1 was – 6.6% (38.6% in 1997; 11.5% in 2000). These results indicate mild iodine deficiency. Conclusion: Our investigations show mild iodine deficiency in Central Siberia demanding continuous adequate iodine prevention. Additional assessment of the iodine intake in the regions with mild iodine deficiency is needed to prevent suboptimal cognitive and psychomotor outcomes.

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Blood-spot thyrotropin radioimmunoassay in a screening program for congenital hypothyroidism.

Clinical Chemistry ◽

10.1093/clinchem/25.6.933 ◽

1979 ◽

Vol 25 (6) ◽

pp. 933-938 ◽

Cited By ~ 8

Author(s):

W A Sadler ◽

C P Lynskey

Keyword(s):

Congenital Hypothyroidism ◽

Screening Program ◽

Rank Correlation ◽

Dried Blood Spots ◽

Recall Rate ◽

Factors Affecting ◽

Blood Spots ◽

Highly Sensitive ◽

Blood Spot ◽

Assay Conditions

Abstract We describe a highly sensitive and precise radioimmunoassay for thyrotropin in dried blood spots on filter paper cards. In a screening program for congenital hypothyroidism, blood-spot thyrotropin concentrations are measured in infants whose blood-spot thyroxine concentrations are in the lower 10%, and this strategy has reduced the recall rate from 1.7% (thyroxine assay alone) to 0.17%. Thyrotropin assay samples consist of discs 4.5-mm in diameter, containing about 6 microL of blood, punched from blood spots. By appropriate attention to assay conditions, a mean least-detectable thyrotropin concentration equivalent to 2.5 milliunits/L plasma has been achieved. Concomitant measurement of thyrotropin by plasma and blood-spot assays in 91 subjects yielded a Spearman rank correlation coefficient of 0.9732. An analysis of variance of the distribution volume of thyrotropin in blood spots and a covariance analysis of factors affecting blood-spot thyroxine results are presented.

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Newborn Iodine Status Is Not Related to Congenital Hypothyroidism

Journal of Nutrition ◽

10.1093/jn/nxaa178 ◽

2020 ◽

Vol 150 (9) ◽

pp. 2429-2434

Author(s):

James L Mills ◽

Elijah C Reische ◽

Kurunthachalam Kannan ◽

Chongjing Gao ◽

Gary M Shaw ◽

...

Keyword(s):

United States ◽

Newborn Screening ◽

Congenital Hypothyroidism ◽

Iodine Deficiency ◽

Neonatal Intensive Care ◽

Screening Program ◽

Iodine Concentration ◽

The United States ◽

Dried Blood Spots ◽

Iodine Status

ABSTRACT Background Severe iodine deficiency or excess during pregnancy can cause congenital hypothyroidism (CH). Iodine deficiency is common in pregnant women in the United States. Objectives We conducted a nested case–control study in a cohort of ∼2.5 million births in California to determine whether iodine status is related to CH in a US population. Methods Dried blood spots from 907 newborns with CH identified by newborn screening and 909 unaffected controls matched by month of birth were obtained from the California Newborn Screening Program to measure whole-blood iodine concentration. Iodine status was compared between cases and controls, and logistic regression was used to assess the association between CH status and blood iodine concentrations. Iodine status was also compared between cases and controls among infants treated in a neonatal intensive care unit (NICU) because CH has been reported in infants exposed to high levels of iodine in the NICU. Results Blood iodine concentrations did not differ significantly between cases (median: 20.0 ng/mL; IQR: 12.1–29.8 ng/mL) and controls (median: 20.3 ng/mL; IQR: 12.5–30.9 ng/mL; P = 0.59). Neither extremely high nor extremely low blood iodine concentrations (1st, 5th, 95th, and 99th percentiles of the distribution) were more common in cases. Among infants treated in NICUs, however, cases had significantly (P = 0.01) higher iodine (median: 22.7 ng/mL; IQR: 16.4–32.1 ng/mL) compared with controls (median: 17.3 ng/mL; IQR: 8.3–26.6 ng/mL). Conclusions CH cases did not have significantly higher or lower iodine in this population, which is reassuring given that maternal iodine deficiency is common in the United States. Among newborns in the NICU, CH cases had higher blood iodine concentrations compared with controls, suggesting that excess iodine exposure in the NICU could be causing CH. It may be beneficial to monitor iodine exposure from surgical procedures, imaging, and iodine-containing disinfectants and to consider non-iodine alternatives.

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Pilot Neonatal Screening Program for Central Congenital Hypothyroidism: Evidence of Significant Detection

Hormone Research in Paediatrics ◽

10.1159/000480293 ◽

2017 ◽

Vol 88 (3-4) ◽

pp. 274-280 ◽

Cited By ~ 7

Author(s):

Débora Braslavsky ◽

Maria Virginia Méndez ◽

Laura Prieto ◽

Ana Keselman ◽

Rosa Enacan ◽

...

Keyword(s):

Congenital Hypothyroidism ◽

Neonatal Screening ◽

Screening Program ◽

Recall Rate ◽

Free T4 ◽

Screening Programs ◽

Screening Study ◽

Term Newborns ◽

Neonatal Screening Program ◽

Congenital Hypopituitarism

Background/Aim: Congenital hypothyroidism (CH) is a heterogeneous entity. Neonatal screening programs based on thyrotropin (TSH) determination allow primary CH diagnosis but miss central CH (CCH). CCH causes morbidity, alerts to other pituitary deficiencies, and is more prevalent than previously thought. We aimed at developing a pilot neonatal screening program for CCH detection. Patients and Methods: A prospective 2-year pilot neonatal screening study based on simultaneous dried blood specimen TSH and thyroxine (T4) measurements was implemented in term newborns aged 2–7 days. Those with T4 ≤4.5 µg/dL (–2.3 SDS) and TSH <10 mIU/L were recalled (suspicious of CCH) and underwent clinical and biochemical assessment performed by expert pediatric endocrinologists. Results: A total of 67,719 newborns were screened. Primary CH was confirmed in 24 (1: 2,821). Forty-four newborns with potential CCH were recalled (recall rate 0.07%) at a mean age of 12.6 ± 4.8 days. In this group, permanent CCH was confirmed in 3 (1: 22,573), starting L-T4 treatment at a mean age of 12.3 ± 6.6 days; 14 boys showed T4-binding globulin deficiency (1: 4,837); 24 had transient hypothyroxinemia (21 non-thyroidal illness and 3 healthy); and 3 died before the confirmation stage. According to initial free T4 measurements, CCH patients had moderate hypothyroidism. Conclusions: Adding T4 to TSH measurements enabled the identification of CCH as a prevalent condition and contributed to improving the care of newborns with congenital hypopituitarism and recognizing other thyroidal disorders.

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Influence of topical iodine-containing antiseptics used during delivery on recall rate of congenital hypothyroidism screening program

Journal of Pediatric Endocrinology and Metabolism ◽

10.1515/jpem-2016-0164 ◽

2017 ◽

Vol 30 (9) ◽

Cited By ~ 1

Author(s):

Majid Valizadeh ◽

Farzaneh Moezzi ◽

Zohreh Khavassi ◽

Mohammad Movahedinia ◽

Seideh Mazloomzadeh ◽

...

Keyword(s):

Phase I ◽

Congenital Hypothyroidism ◽

Phase Ii ◽

Screening Program ◽

Recall Rate ◽

Local Hospital ◽

Screening Programs ◽

Blood Specimens ◽

Heel Prick ◽

Tsh Levels

AbstractBackground:The proportion of newborns recalled during neonatal screening programs for congenital hypothyroidism (CH) varies substantially by country and may be higher in settings where povodine iodine (PVP-I) is used during delivery. We assessed this hypothesis by substituting PVP-I for chlorhexidine (CHL) and evaluated the reduction in the recall rate of the Irainian newborn screening program.Methods:This study investigated 2282 neonates of mothers admitted to a local hospital for delivery between December 2012 and October 2013. We measured thyorid stimulating hormone (TSH) levels in heel-prick blood specimens of infants, aged between 3 and 5 days, born to mothers who received PVP-I (phase I) and those who received CHL after withdrawal of PVP-I from obstetric procedures (phase II). Then we compared the median TSH levels and the recall rate based on a TSH level ≥5 mU/L.Results:Of 2282 cases, 1094 infants were born to mothers exposed to PVP-I during phase I (PVP-I group) and 1188 ones were born to mothers exposed to chlorhexidine in phase II (CHL group); 6.56% of the PVP-I group and 1.91% of the CHL group were recalled later during screening (p<0.001). The median TSH level was significantly higher in the PVP-I group compared to the CHL group (1.35 vs. 1.00, p<0.001).Conclusions:Replacement of iodine-containing antiseptics by iodine-free ones, during delivery resulted in a significant reduction in the recall rate of the Iranian screening program for CH.

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Congenital Hypothyroidism: An Audit and Study of Different Cord Blood Screening TSH Values in a Tertiary Medical Centre in Malaysia

Advances in Endocrinology ◽

10.1155/2015/387684 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6

Author(s):

Sze Lyn Jeanne Wong ◽

Muhammad Yazid Jalaludin ◽

Azriyanti Anuar Zaini ◽

Nurshadia Samingan ◽

Fatimah Harun

Keyword(s):

Cord Blood ◽

Congenital Hypothyroidism ◽

Screening Program ◽

Recall Rate ◽

Medical Centre ◽

Asian Countries ◽

Predictive Values ◽

Screening Programs ◽

Premature Babies ◽

Blood Screening

Mothers are often discharged within 24 hours in most Asian countries. Therefore, our screening programs for congenital hypothyroidism (CH) must consider the value of cord blood TSH. Our objectives were to compare the incidence of CH, positive predictive values, and recall rates using different cord blood TSH values. We also reviewed the results of the second-screening program for premature babies. 99.7% (n=25,757) of all newborns were screened from 1st January 2009 to 31st December 2013. Babies with cord blood TSH > 25 mIU/L or 20–25 mIU/L and FT4<20 pmol/L were recalled for a repeat venous TSH and FT4 on days 3–5 of life to confirm CH. Twenty-two babies were confirmed to have CH, an incidence of 1:1170. Five were premature. Eleven term babies had cord blood TSH>30 mIU/L and six had values 25.1–30 mIU/L. Lowering the recall cut-off value to 20 mIU/L would double the recall rate from 0.63% (n=163) to 1.3% (n=340) with no additional cases detected, whereas using 30 mIU/L would have missed 35% of cases. The incidence of CH was similar, 1:1515, when using either cut-off 20 mIU/L or cut-off 25 mIU/L but lower, 1:2380, when using 30 mIU/L. We recommend the screening cord blood TSH cut-off should be 25 mIU/L and screening for premature babies should be continued.

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An audit to assess the impact of increasing the borderline blood spot TSH cut-off on the detection of cases of congenital hypothyroidism (CHT) identified via newborn screening

Endocrine Abstracts ◽

10.1530/endoabs.36.p82 ◽

2014 ◽

Author(s):

Lesley Tetlow ◽

Sarah Ehtisham ◽

Beverly Hird ◽

Claire Manfredonia ◽

Daniella Nice ◽

...

Keyword(s):

Newborn Screening ◽

Congenital Hypothyroidism ◽

The Impact ◽

Blood Spot

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The impact of receiving a diagnosis of congenital hypothyroidism on families

Endocrine Abstracts ◽

10.1530/endoabs.36.oc5.2 ◽

2014 ◽

Author(s):

Sabah Alvi ◽

Julia Priestley ◽

Amanda Whitehead ◽

Jenny Walker ◽

Talat Mushtaq

Keyword(s):

Congenital Hypothyroidism ◽

The Impact

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Birth prevalence of tetrahydrobiopterin deficiency in China: data from the national newborn screening program, 2013–2019

Journal of Pediatric Endocrinology and Metabolism ◽

10.1515/jpem-2021-0077 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Xuelian Yuan ◽

Jun Zhu ◽

Hanmin Liu ◽

Liangcheng Xiang ◽

Yongna Yao ◽

...

Keyword(s):

Screening Program ◽

National Level ◽

Recall Rate ◽

Birth Prevalence ◽

Live Births ◽

Provincial Level ◽

Tetrahydrobiopterin Deficiency ◽

Total Prevalence ◽

Entire Country ◽

Northern Regions

Abstract Background Tetrahydrobiopterin deficiency (BH4D), a less common form of hyperphenylalaninemia (HPA), can lead to severe developmental retardation if untreated. Little has been reported on the prevalence of BH4D among live births worldwide. This study examined its prevalence across China and between geographical areas within the country. Methods We analyzed data from the Chinese national screening program for HPA in newborns between 2013 and 2019. BH4D prevalence was examined by province, region and the entire country. Provincial-level prevalence was estimated from the number of confirmed BH4D cases and screened newborns, after adjusting for HPA-positive recall rate. Regional- and national-level prevalences were estimated by summing provincial-level prevalences after weighting them by the number of live births. A Poisson distribution was assumed in order to calculate 95% confidence intervals (CIs) for prevalence. Results Among 107,078,115 newborns screened for HPA in China, 380 with BH4D were identified, corresponding to a total prevalence of 3.8 per 1,000,000 live births. Prevalence was higher in eastern regions (5.9 per 1,000,000) and northern regions (4.1 per 1,000,000) of China than in southern regions (1.6 per 1,000,000) or northwestern regions (1.7 per 1,000,000). Across the entire country, 3.9% cases of HPA were diagnosed as BH4D, and this proportion reached as high as 15.1% in the southern part of the country. Conclusions These first insights into BH4D prevalence across China suggest slightly higher prevalence than in other countries, and it varies substantially by region. More attention should be paid to early diagnosis and timely treatment of BH4D.

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National Colorectal Cancer Screening Program in Lithuania: Description of the 5-Year Performance on Population Level

Cancers ◽

10.3390/cancers13051129 ◽

2021 ◽

Vol 13 (5) ◽

pp. 1129

Author(s):

Audrius Dulskas ◽

Tomas Poskus ◽

Inga Kildusiene ◽

Ausvydas Patasius ◽

Rokas Stulpinas ◽

...

Keyword(s):

Colorectal Cancer ◽

Quality Assurance ◽

Cancer Screening ◽

Colorectal Cancer Screening ◽

Screening Program ◽

Histopathological Examination ◽

Insurance Fund ◽

Crc Screening ◽

Cancer Screening Program ◽

The Impact

We aimed to report the results of the implementation of the National Colorectal Cancer (CRC) Screening Program covering all the country. The National Health Insurance Fund (NHIF) reimburses the institutions for performing each service; each procedure within the program has its own administrative code. Information about services provided within the program was retrieved from the database of NHIF starting from the 1 January 2014 to the 31 December 2018. Exact date and type of all provided services, test results, date and results of biopsy and histopathological examination were extracted together with the vital status at the end of follow-up, date of death and date of emigration when applicable for all men and women born between 1935 and 1968. Results were compared with the guidelines of the European Union for quality assurance in CRC screening and diagnosis. The screening uptake was 49.5% (754,061 patients) during study period. Participation rate varied from 16% to 18.1% per year and was higher among women than among men. Proportion of test-positive and test-negative results was similar during all the study period—8.7% and 91.3% annually. Between 9.2% and 13.5% of test-positive patients received a biopsy of which 52.3–61.8% were positive for colorectal adenoma and 4.6–7.3% for colorectal carcinoma. CRC detection rate among test-positive individuals varied between 0.93% and 1.28%. The colorectal cancer screening program in Lithuania coverage must be improved. A screening database is needed to systematically evaluate the impact and performance of the national CRC screening program and quality assurance within the program.

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