OBJECTIVEDocument the prevalence of congenital hypothyroidism in Zhejiang Province, by neonatal screening of TSH.

METHODSDELFIA neonatal TSH kit was applied for the quantitative determination of thyrotropin in blood specimens dried on filter paper.

RESULTAmong the 42 979 newborns, 112 had elevated hTSH concentration in blood. All had T3, T4 and TSH concentrations measured in serum and 29 were diagnosed as congenital hypothyroidism. The diagnosis time was 13 to 59 days and mean time was (27.9+/-9.2) days.

CONCLUSIONThe incidence of congenital hypothyroidism in Zhejiang Province is not low. The TSH screening in newborns is significant in eugenics and the improvement of population quality.

Congenital Hypothyroidism ; Female ; Humans ; Hypothyroidism ; epidemiology ; Infant, Newborn ; Male ; Neonatal Screening ; Sex Factors ; Thyrotropin ; blood

OBJECTIVEThe retrospective study was carried out to investigate the nation-wide neonatal screening program in the past 22 years in China. This study aimed to summarize the experience, analyze the questions and concerns in the screening program.

METHODSAll data on the national neonatal screening in the past 22 years were from National Center for Clinical Laboratory. Study items included the development and mode of the program, screening method adopted as well as the clinical records of prevalence, treatment and follow-up etc.

RESULTSNeonatal screening has become universal since 1985 in China. There were three modes of screening and treatment. From 1985 to 2006, a total of 13,229,242 newborns were screened for congenital hypothyroidism (CH) and 6505 were diagnosed as CH at a prevalence of 49.2/100,000; a total of 13,666,750 newborns were screened for phenylketonuria (PKU), and 1,170 were diagnosed as PKU at a prevalence of 8.6/100,000. The prevalence of CH increased year by year and the western regions in China had a much higher prevalence. The prevalence of PKU was relatively more steady than that of CH in China.

CONCLUSIONSNeonatal screening is of paramount importance in preventing mental retardation and developmental delay after CH and PKU. It is necessary to attach more importance to increase the rate of coverage, screening and treatment, as well as social awareness of neonatal screening. It is important to focus on establishment of new screening techniques so as to improve the level of child health care in China.

China ; epidemiology ; Congenital Hypothyroidism ; epidemiology ; Humans ; Infant, Newborn ; Neonatal Screening ; Phenylketonurias ; epidemiology ; Prevalence ; Retrospective Studies

OBJECTIVESTo summarize neonatal screening for phenylketonuria (PKU) and congenital hypothyroidism (CH) in China, to further clarify incidence of the two kinds of diseases in newly-born babies, and to explore issues in neonatal screening and their solutions.

METHODSNeonatal screening for PKU and CH was conducted by 39 neonatal screening centers all over the country, sponsored by the Group of Neonatal Screening, Chinese Society of Child Health Care, Chinese Preventive Medical Association and the Center for Neonatal Screening Quality Control Laboratory, National Center for Clinical Laboratories (NCCL). In each infant a heel prick blood sample was collected at 72 hours postnatal onto standard filter paper. PKU was screened by bacterial inhibition assay and fluorometric method, and CH was screened by TSH measurement by time-resolved fluorescence immunoassay (TRFIA), fluorescence enzyme immunoassay (FEIA) and enzyme immunoassay (EIA).

RESULTSFrom 1985 to 2001 in China, totally of 5 817 280 newborns were screened for PKU, 522 cases of PKU detected with an incidence of 1:11 144, and 5 524 019 newborns were screened for CH, 1 836 cases of CH detected with an incidence of 1:3 009. Annual average number of newborns screened for congenital genetic diseases was increased by 45.5% in recent six years.

CONCLUSIONSNeonatal screening was developed quickly in China in recent years, especially in some developed cities, such as Shanghai with a coverage of 98.3% in 2001. But, its coverage was about only 10% in China as a whole. In development of neonatal screening, it is necessary to attach more importance to quality of screening and increasing coverage of screening, as well as gradual development of new screening techniques for other neonatal preventable diseases, in addition to PKU and CH, and their application, and improvement of level of child health care in China.

China ; epidemiology ; Congenital Hypothyroidism ; Fluorescence Polarization Immunoassay ; Fluorometry ; Humans ; Hypothyroidism ; epidemiology ; Immunoenzyme Techniques ; Infant, Newborn ; Neonatal Screening ; Phenylketonurias ; epidemiology ; Thyrotropin ; blood

OBJECTIVETo estimate the prevalence of subcretins in 8 minorities of Yunnan province and to provide scientific basis for public health policy-making, as well as for prevention and control of iodine deficiency disorders.

METHODSFour thousand two hundred and twenty-two minority school children aged 8-12 years selected from 29 schools in 8 minority counties were measured by Combined Raven's Test in China (CRT-C(2)) and Jinyi Psychomotor test Battery (JPB).

RESULTSAverage of intelligence quotient (IQ) on 4,222 children was 91 +/- 19. Among 277 pupils with IQ between 55 - 69, 119 of them showed abnormal on JPB test and 5.4% of the children was found to have Goiter under ultrasonography. Median level of urinary iodine was 466.9 microg/L, and the qualified rate of iodized salt was 94.9%.

CONCLUSIONThe estimated prevalence rate of subcretin was 2.8%.

Child ; Child Development ; China ; epidemiology ; Congenital Hypothyroidism ; epidemiology ; Ethnic Groups ; Female ; Humans ; Intelligence Tests ; Male ; Prevalence

China ; epidemiology ; Congenital Hypothyroidism ; diagnosis ; epidemiology ; Humans ; Infant, Newborn ; Neonatal Screening

OBJECTIVETo summarize and analyze neonatal screening results for congenital hypothyroidism (CH) in parts of Yunnan Province, China.

METHODSA total of 236 218 newborns (121 463 males and 114 755 females) who were born in Zhaotong City, Qujing City, Lijiang City, and Diqing Tibetan Autonomous Prefecture of Yunnan Province, China, between July 2012 and April 2014 were screened for CH. The original blood smear was re-tested if the thyroid stimulating hormone (TSH) level in heel blood was ≥8 μIU/L in the initial screening. The newborns with positive TSH results were called back for further diagnosis by measuring blood TSH and free thyroxine (FT4) levels.

RESULTSAmong 236 218 newborns, the pass rate of blood smears, re-acquisition rate of unqualified blood smears, and recall rate of suspected cases were 96.67%, 81.75%, and 73.02%, respectively. Sixty-six cases of CH were confirmed, among which 36 were male infants and 30 were female infants (P>0.05). The incidence rate of CH was 1/3 579, which was significantly lower than the national average rate (1/2 034; P<0.01). The gestational age of CH newborns was mostly between 37 to 42 weeks, and only 3% were born at a gestational age of >42 weeks. Most of the CH newborns had normal birth weight. The CH newborns with a body length of <50 cm accounted for 32%.

CONCLUSIONSThe incidence of CH in Yunnan Province is lower than the national average. There are no specific clinical features in CH newborns. The neonatal screening in Yunnan Province needs further improvement.

China ; epidemiology ; Congenital Hypothyroidism ; blood ; epidemiology ; Female ; Humans ; Infant, Newborn ; Male ; Neonatal Screening ; Thyrotropin ; blood

OBJECTIVE: To investigate the prevalence rate of hypothyroidism in children with β-thalassemia major (β-TM) and its risk factors. METHODS: A total of 86 children with β-TM treated and followed up in the Department of Pediatrics of the Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai Municipal Maternal and Child Health Care Hospital from August 2018 to August 2020 were enrolled. The clinical data of the children were analyzed to investigate the prevalence rate of hypothyroidism in children with β-thalassemia major (β-TM) and its risk factors. RESULTS: The prevalence rate of hypothyroidism in children with β-TM in Zhuhai area was 17.4%. The level of serum ferritin(SF) (4948.27±1225.33 μg/L) in hypothyroidism children was significantly increased(t=10.273，P<0.05). The prevalence rate of hypothyroidism was significantly higher in β-TM children(age ≥10 years old, SF ≥2 500 μg/L and irregular iron removal) (P<0.05). Logistic regression result showed that age ≥10 years old was the independent risk factor affecting the increasing of hypothyroidism rate in the children. The levels of SF(3880.60±1269.17 μg/L), TSH(4.43±1.52 mIU/L) and the prevalence rate of hypothyroidism(37.14%)(P<0.05) were higher for the children in irregular iron removal group. CONCLUSION The prevalence rate of hypothyroidism in children with β-TM in Zhuhai area is high, and it is related to the age ≥10 years old, SF ≥2 500 μg/L and irregular iron removal of the children.
Child ; Humans ; Hypothyroidism/epidemiology* ; Iron Overload ; Prevalence ; Risk Factors ; beta-Thalassemia/epidemiology*

BACKGROUND: Although congenital hypothyroidism (CH) has been widely studied in Western countries, CH incidence at different administrative levels in China during the past decade remains unknown. This study aimed to update the incidence and revealed the spatial pattern of CH incidence in the mainland of China, which could be helpful in the planning and implementation of preventative measures. METHODS: The data used in our study were derived from 245 newborns screening centers that cover 30 provinces of the Chinese Newborn Screening Information System. Spatial auto-correlation was analyzed by Global Moran I and Getis-Ord Gi statistics at the provincial level. Kriging interpolation methods were applied to estimate a further detailed spatial distribution of CH incidence at city level throughout the mainland of China, and Kulldorff space scanning statistical methods were used to identify the spatial clusters of CH cases at the city level. RESULTS: A total of 91,921,334 neonates were screened from 2013 to 2018 and 42,861 cases of primary CH were identified, yielding an incidence of 4.66 per 10,000 newborns screened (95% confidence interval [CI]: 4.62-4.71). Neonates in central (risk ratio [RR] = 0.84, 95% CI: 0.82-0.85) and western districts (RR = 0.71, 95% CI: 0.69-0.73) had lower probability of CH cases compared with the eastern region. The CH incidence indicated a moderate positive global spatial autocorrelation (Global Moran I value = 0.394, P  < 0.05), and the CH cases were significantly clustered in spatial distribution. A most likely city-cluster (log-likelihood ratio [LLR] = 588.82, RR = 2.36, P  < 0.01) and 25 secondary city-clusters of high incidence were scanned. The incidence of each province and each city in the mainland of China was estimated by kriging interpolation, revealing the most affected province and city to be Zhejiang Province and Hangzhou city, respectively. CONCLUSION This study offers an insight into the space clustering of CH incidence at provincial and city scales. Future work on environmental factors need to focus on the effects of CH occurrence.
China/epidemiology* ; Cluster Analysis ; Congenital Hypothyroidism/epidemiology* ; Humans ; Incidence ; Infant, Newborn ; Retrospective Studies ; Spatial Analysis

OBJECTIVE: To describe the thyroid function abnormality of first-trimester twin pregnant women according to different references, and to explore its association with preterm delivery. METHODS: Participants, first-trimester twin pregnant women, were recruited at Peking University Third Hospital from March 2017 to February 2020. The thyroid hormone reference for ordinary adults identified on the assay kits by Siemens incorporation, thyroid hormone reference specifically for singleton pregnancy established previously, and thyroid hormone reference specifically for twin pregnancy established previously were used in the description of hypothyroidism and hyperthyroidism for first-trimester twin pregnant women. Thyroid autoantibody reference identified on the assay kits by Siemens incorporation was used in the description of positive thyroid autoantibody. Multivariable log-binomial regression was conducted to examine the association between thyroid function and preterm delivery, in which normal pregnant women according to the three references and normal pregnant women according to twin pregnancy reference accompanied with negative thyroid autoantibody were taken as control respectively. RESULTS: A total of 570 twin pregnant women were finally included. Rates of hypothyroidism according to the three references were 1.2%, 1.6% and 3.5%, respectively. Rates of hyperthyroidism according to the three references were 32.6%, 18.1% and 1.1%, respectively. After adjustment for potential confounding factors, risk of preterm delivery significantly increased in pregnant women with hyperthyroidism according to the twin specific pregnancy reference [adjusted relative risk (ARR)=1.41, 95%CI: 1.14-1.75], while no significant increase was found in those with normal thyroid function according to the twin specific pregnancy reference but hyperthyroidism according to the singleton specific pregnancy reference (ARR=1.00, 95%CI: 0.81-1.25) and in those with hyperthyroidism purely according to the ordinary adult reference (ARR=1.06, 95%CI: 0.85-1.32), compared with those normal according to all the references. Risks of preterm delivery almost significantly or significantly increased in pregnant women with hypothyroidism according to the ordinary adult or singleton specific pregnancy reference (ARR=1.40, 95%CI: 0.88-2.22) and those with hypothyroidism according to the twin specific pregnancy reference (ARR=1.53, 95%CI: 1.03-2.28). Overall analysis of thyroid function according to the twin specific pregnancy reference and thyroid autoantibody showed that risks of preterm delivery almost significantly or significantly increased in pregnant women with simple hypothyroidism (ARR=1.46, 95%CI: 0.93-2.27), simple positive thyroid autoantibody (ARR=1.32, 95%CI: 1.15-1.52), and hypothyroidism accompanied with positive thyroid autoantibody (ARR=1.78, 95%CI: 1.30-2.44), compared with those normal according to the twin specific pregnancy reference with negative thyroid autoantibody. CONCLUSION The ordinary adult reference and that of singleton pregnancy may lead to under-diagnosis of hypothyroidism and over-diagnosis of hyperthyroidism in first-trimester twin pregnant women. Compared with pregnant women with normal thyroid function, those missed in the diagnosis of hypothyroidism were at a higher risk of preterm delivery, while those over-diagnosed as hyperthyroidism had a similar risk of preterm delivery, indicating a need to develop and generalize twin-pregnancy-specific reference on common indicators of thyroid function. Moreover, the thyroid autoantibody should be taken into consideration in the prenatal diagnosis and treatment to twin pregnant women with hypothyroidism.
Adult ; Female ; Humans ; Hypothyroidism/epidemiology* ; Infant, Newborn ; Pregnancy ; Pregnancy Complications/epidemiology* ; Pregnancy Trimester, First ; Pregnant Women ; Premature Birth/epidemiology*

OBJECTIVETo understand the level of thyroid function and the prevalence of the thyroid diseases of children in high water iodine areas.

METHODTwo primary schools were selected by purposive sampling from Haixing county, Hebei province in April 2010. A total of 371 children were selected from six classes by cluster sampling in the schools. Morning-urine and venous blood (5 ml) were collected to measure the levels of urinary iodine, free triiodothyronine (FT(3)), free thyroxine (FT(4)) and sensitive thyroid-stimulating hormone (sTSH) in serum and to evaluate the iodine status and thyroid function of children.

RESULTSThe median urinary iodine of the children was 1032.08 µg/L. Overall, 96.2% (357/371) of the children's urinary iodine were ≥ 300 µg/L and 68.5% (254/371) were ≥ 800 µg/L. The level of FT(3) and FT(4) were (6.28 ± 0.81) pmol/L and (16.37 ± 2.72) pmol/L, respectively. The median of sTSH was 4.01 mU/L. The FT(4) among boys ((16.63 ± 2.60) pmol/L) was significantly higher than that among girls ((15.99 ± 2.85) pmol/L) (P < 0.05). Overall, 44 subjects were diagnosed as thyroid disease (11.9%), 25 were subclinical hypothyroidism (57% of the total patients), 4 were hypothyroidism (9%), 10 were hyperthyroidism (23%) and 5 were subclinical hyperthyroidism (11%). In the urinary iodine of 200 - 799 µg/L, the prevalence of thyroid disease and hypothyroidism were 6.3% (7/111) and 14.6% (27/254), respectively. When urinary iodine ≥ 800 µg/L, the prevalence of thyroid diseases and hypothyroidism were 3.6% (4/111) and 8.3% (21/254), respectively.

CONCLUSIONMost of the children in high water iodine areas had excessive iodine intake. Levels of the children's thyroid hormone were within the normal range. The prevalence of thyroid disease were high, in these areas and the thyroid disease were mainly the subclinical hypothyroidism.

Adolescent ; Child ; China ; epidemiology ; Female ; Humans ; Hypothyroidism ; epidemiology ; Iodine ; analysis ; urine ; Male ; Prevalence ; Thyroid Function Tests ; Water ; chemistry