安徽省全民普食磺盐前后新生儿TSH水平分析

目的 通过检测新生儿促甲状腺激素（ＴＳＨ）水平,比较安徽省全民普食碘盐前和普食磺上多后居民碘营养状况。方法 采用免疫放射法（ＩＲＭＡ）对新生儿脐带血ＴＳＨ水平进行了测定。结果 新生儿脐带血ＴＳＨ〉５ｍＵ／Ｌ者,１９９５年为３２．３％,１９９７年为２７．８％。结论 １９９７年安徽省居民碘缺乏危害程度料１９９５年减轻,但摄入的碘仍然不够,需要进一步加强全民普食碘盐防治措施。     

吉林省孕妇产前尿碘检测结果分析

吉林省是缺碘地区,据1987年外环境碘水平调查,全省水碘均值为2.99μg/L,<5μg/L占85％(0～26.05)未发现高碘区。因此长期以来,始终坚持以食盐加碘为主防治碘缺乏的方针。特别是1994年开始全民普及碘盐,全省居民碘营养水平有很大提高。据1997年全省“PPS”抽样调查:8～10岁儿童甲肿率(B超法)为6.75％;尿碘中位数为384.2μg/L;居民碘盐合格率为92.30％。长春市4644名托幼儿童尿碘中位数为311.82μg/L。1997年全省各市(州)县、(市、区)居民碘盐合格率为99.24％。以上结果表明,全省大多数人群缺碘状态已基本得到纠正,一些主要指标已经达到或接近达到国家消除碘缺乏病标准。但是也发现一个不可忽视的问题,即新生儿脐带血TSH水平,1997年全省抽检900例新     

银川地区1693例新生儿TSH值动态分析

补碘可有效的防治IDD,但防治效果的监测是非常重要的环节,WHO和ICCIDD曾推荐采用灵敏的免疫放射法(IRMA)检测新生儿脐带血的TSH值,作为人群缺碘状况监测指标。宁夏自治区于1995年度开始向全区居民普及加碘食盐。普及碘盐前后,分别采集银川地区新生儿脐带血,采用IRMA进行检测,以期了解新生儿TSH水平和简单评价干预措施及效果分析。     

湖北省新生儿脐带血TSH水平及其相关因素研究

目的探讨碘营养状况正常情况下的新生儿脐带血TSH水平及其相关因素的影响,为建立适合我国国情的新生儿TSH正常值范围提供依据.方法在湖北省选取普及碘盐且碘营养状况良好的4个市区,采集孕妇尿样及其新生儿脐带血血样,测定孕妇尿碘和新生儿脐带血TSH水平,TSH值测定采用ELISA法.结果共采集新生儿脐带血879份,测定TSH中位数为3.425 mU/L,P97为10.461 mU/L,＞5 mU/L的为27.0%,且TSH水平受新生儿出生方式和出生时间的影响.结论在碘营养状况良好的环境下,新生儿脐带血TSH水平呈不稳定性,充分说明使用TSH＞5mU/L的比率＜3%的标准来评判新生儿脐带血TSH结果需要修改.     

全民食盐加碘后闽东南沿海居民碘营养状况动态变化趋势

目的了解全民食盐加碘后闽东南沿海居民碘营养状况动态变化趋势.方法 1995年至2001年每隔1年从闽东南沿海11个沿海县(市、区)各抽取8～10岁儿童1200名调查甲状腺肿比例,每个县(市、区)再抽检210名儿童进行尿碘水平和家中盐碘含量的测定,观察新生儿脐带血(全血)TSH水平.结果儿童甲肿率持续下降,2001年已达3.8%,所有县(市、区)儿童尿碘中位数均＞100 μg/L.结论闽东南沿海居民经实施全民食盐加碘干预后,居民碘营养状况得到明显改善.     

碘营养充足地区新生儿脐带血TSH切点值的研究

目的 探讨新生儿脐带血促甲状腺激素（TSH）测定在临床应用的可行性和在碘营养充足的情况下新生儿脐带血TSH的切点值。方法 选择采取食盐加碘干预措施后当地居民碘营养充足地区的孕妇作为的研究对象,观察指标有孕妇尿碘、新生儿脐带血TSH和新生儿足跟血TSH水平及相关因素。结果 ①碘营养充足地区碘营养充足的孕妇所分娩的新生儿脐带血TSH的切点值为8.3mU/L,高于国际标准5mU/L;②新生儿脐带血TSH与足跟血TSH呈正相关关系。结论 新生儿脐带血TSH测定用于碘缺乏病的监测是可行的,有必要建立适合我国的新生儿脐带血TSH切点值。     

永定县新生儿全血TSH水平监测结果分析

新生儿全血TSH水平反映机体碘营养状况及其变化的一项非常敏感的指标，也是用来评价人群碘营养状况的最敏感和可靠的指标。永定县从1984年开始用碘盐补充人体碘需要来消除碘缺乏病。曾于1996年、1999年监测新生儿脐带血TSH水平，又于2002年、2003年监测新生儿足跟血TSH水平，现将结果分析如下。     

福建省1999年碘缺乏病监测报告

为评价全民食盐加碘对福建省碘缺乏病的防治效果，于1999年采用容量比例概率法（PPS）在全省调查了30个县1200名8－10岁儿童的甲状腺肿大率（B超法和触诊法），1196份盐碘，387份尿碘，702份新生儿脐带血TSH，结果显示该群体甲状腺肿大率B超法为6．25％，触诊法为4．20％，尿碘中位数为203．9μg/L，合格碘盐覆盖率65．1％，新生儿脐带血TSH大于5mu／L占21．7％，通过四年以全民食盐加碘为主的干预措施后，碘缺乏病病情已明显下降。     

消除碘缺乏病评估指标相关性的研究

目的研究碘营养充足状态下新生儿脐带血与足跟血TSH水平间及其同母体孕期尿碘的关系。方法选取河南省碘营养良好地区(居民户盐碘>20 mg／kg,8～10岁儿童尿碘中位数≥100 mg/L,8～10岁儿童B超法甲状腺肿大率<5％)作为调查点,收集孕妇妊娠各个不同时期的尿样测定尿碘。采集新生儿脐带血和足跟血,采用酶免疫分析和放射免疫分析方法测定TSH水平。结果采集不同时期孕妇尿样956份,尿碘中位数255．4μg/L,最小值为32．6μg／L,最大值为2 153．0μg／L。采集新生儿脐带血合格样品289人份,TSH均值为2-32 mU／L;采集新生儿足跟血合格样品246人份,TSH均值为1．22 mU／L,脐带血与足跟血TSH相比差异有统计学意义(t=2．645,P<0．01)。在孕期尿碘≥100μg／L的母亲中,其新生儿脐带血TSH>5mU／L所占比例<3％,新生儿足跟血TSH也显示同样结果。结论孕期碘营养良好是保证新生儿脐带血TSH达标的前提条件,在孕期碘营养良好状态下,盐碘、尿碘、甲状腺肿大率和新生儿脐带血TSH各项指标间将会保持良好的相关关系,以新生儿脐带血TSH作为监测指标可以更灵敏的反映人群的碘营养状态。     

抚顺市农村和城区新生儿脐带血TSH水平分析

为了解供应碘盐后抚顺市碘缺乏病病区出生的新生儿碘营养状况和评价补碘防治效果，我们对农村和城区新生儿脐带血TSH进行了测定，结果报告如下。     

供碘盐地区与未供碘盐地区新生儿TSH值分布的对比观察

在苏南地区供碘盐八年以上的溧阳等四个县（市）和未供碘盐的无锡等四个县（市）对新生儿ＴＳＨ水平进行了研究。结果显示，不同尿碘水平的地区，新生儿ＴＳＨ水平分布呈现不同的分布特征，供应碘盐地区的新生儿ＴＳＨ水平分布出现了明显的左移；同时还发现用人群尿碘水平和用新生儿ＴＳＨ水平评价碘营养状况时出现了分离现象。     

河南省新生儿脐带血（全血）TSH水平调查

采用高灵敏的滤纸血斑ＴＳＨ免疫放射分析法（ＩＲＭＡ），对用ＰＰＳ法抽取的３０个县（区）新生儿脐带血全血ＴＳＨ水平进行了测定，以期评价河南省消除ＩＤＤ的进程状况。全省拟采１４４０份，最后测定的有效血样１１９１份。结果表明，新生儿ＴＳＨ值大于５ｍＩＵ／Ｌ者占４７．９％，其频数分布明显向高值偏移，非正常产新生儿的ＴＳＨ值明显高于正常产。提示河南省ＩＤＤ防治状况依然十分严重，距ＩＤＤ消除标准相差甚远，建议加大力度全面实施碘干预措施。     

哈尔滨市新生儿脐带血TSH切点值的建立

目的　尽快建立适合我国实际情况的新生儿脐带血促甲状腺激素（TSH）切点值。方法　在指定地区对孕妇的碘营养状况进行横断面调查,在证实该地区碘营养状况正常后,于分娩前采集孕妇尿样和盐样,分娩时采集其新生儿脐带血血样,TSH测定采用ELISA方法。结果　哈尔滨市孕妇尿碘中位数为284μg/L,新生儿脐带血TSH>5mU/L的比率为34.1％,TSH>10mU/L的比率为8.8％;新生儿脐带血TSH第95％和97％的分位值是13.37mU/L和15.39mU/L。在正常碘营养条件下,新生儿脐带血TSH值仅受出生方式的影响,孕妇的尿碘水平、年龄、职业、文化程度、家庭收入对2种出生方式新生儿脐带血TSH均无影响。结论　通过哈尔滨市新生儿脐带血TSH研究,为建立适合我国实际情况的新生儿脐带血TSH切点值提供了科学依据。     

Postpartum maternal iodine status and the relationship to neonatal thyroid function.

Iodine deficiency in the postpartum period has the potential to affect neonatal neuropsychointellectual development. We performed a cross-sectional study involving 50 postpartum women and their neonates, measuring maternal urine iodine, breast milk iodine, and neonatal thyroid stimulating hormone (TSH), and examining their interrelationships. Women were studied at a median (range) of 4 (3-9) days postpartum. Moderate to severe iodine deficiency (defined by urine iodine concentration < 50 microg/L) was found in 29 of the 50 subjects (58%). The median +/- standard deviation (SD) urine iodine was 46.8 +/- 28.5 microg/L and the mean urine iodine expressed in micrograms per gram of creatinine was 86.6 +/- 45.6. The median (range) breast milk iodine was 84.0 microg/L (25.0-234.0). Breast milk iodine was significantly correlated with urine iodine in micrograms per gram of creatinine (r = 0.52, p < 0.001) but not with urine iodine measured in micrograms per liter (r = 0.19, p = 0.2). Six percent of neonates had whole-blood TSH values of greater than 5 mIU/L. Neonatal TSH levels were positively correlated with higher breast milk iodine (r = 0.42, p = 0.003). There was no significant correlation between neonatal TSH levels and the mother's urine iodine content. There is a high prevalence of iodine deficiency in these lactating postpartum subjects. Urine iodine as micrograms per gram of creatinine is a good predictor of breast milk iodine content. In our study, higher breast milk iodine was correlated with a higher neonatal TSH. The impact of breast milk iodine content on neonatal TSH levels and neuropsychointellectual development needs further study.     

Iodine insufficiency and neonatal hyperthyrotropinaemia in Hong Kong

OBJECTIVES 23% of the neonatal hypothyroidism in Hong Kong is transient. The present study aims to evaluate iodine excretion in healthy pregnant women in Hong Kong and to determine whether iodine insufficiency may occur in the local population to account for the type of neonatal thyroid dysfunction seen in our screening programme. SUBJECTS Pilot screening of urinary iodine excretion was determined in 253 healthy pregnant women between 32 and 36 weeks gestation. Fetal and maternal thyroid function in relation to urinary iodine excretion was evaluated in another 55 pregnant women who had given birth to infants with cord blood TSH ≥ 16 mIU/l (95th percentile of the cord blood TSH screening programme) and the results were compared to a control group of 160 healthy women whose infants had cord blood TSH < 16 mIU/l. RESULTS Using a cut-off value of 0.79 μmol/l, a level as defined by WHO as iodine deficiency, we found that 35.8% of the pregnant women had urinary iodine concentrations below this cut off value. We demonstrated that the existence of borderline iodine supply affected the maternal and fetal thyroid function as evidenced by (i) a negative correlation between maternal TSH and urinary iodine concentration, (ii) higher cord blood TSH in those infants whose mothers had a low urinary iodine concentration as compared to those in whose mothers it was normal, (iii) women who had given birth to infants with cord blood TSH ≥6 mIU/l had lower urinary iodine concentrations and serum fT4 levels as compared to mothers who had given birth to infants with normal cord TSH levels, and their offspring also had higher cord blood thyroglobulin levels. CONCLUSION Although Hong Kong is not a goitrous area, borderline iodine deficiency exists. Iodization of salt in our community could obviate the necessity for iodine supplements in pregnant women and other at-risk groups.     

Maternal and neonatal thyroid function at birth in an area of marginally low iodine intake.

Thyroid function was evaluated in cord serum of healthy full-term newborns and compared to that of mothers immediately after parturition. The study was carried out in an area without overt iodine deficiency, but with a marginal iodine supply (less than 100 micrograms/day in 80% of women). The aim of the study was to delineate the interrelationships between the thyroid statuses of mother and child at birth. Maternal thyroid function was characterized at delivery by relative hypothyroxinemia; increased T3/T4 ratios, indicating preferential T3 secretion; slightly increased TSH levels within the normal range in 97% of women; increased serum thyroglobulin (TG) values, which were above normal in 60% of women; and also goiter formation in almost 10% of women. The findings indicated glandular stimulation and confirmed our earlier reports that pregnancy constitutes a stress for the maternal thyroid economy, enhanced by the limited availability of iodine in the diet. By contrast, newborns showed a strikingly distinct pattern: there was no relative hypothyroxinemia and free T4 levels were significantly higher than in the respective mothers (19.4 vs. 14.7 pmol/L; P less than 0.001). In spite of these differences, however, mean neonatal TSH and TG levels were significantly higher than maternal values, respectively 6.0 vs. 1.9 mU/L for TSH (P less than 0.001) and 70 vs. 40 micrograms/L for TG (P less than 0.001). Furthermore, neonatal TG and TSH levels increased in parallel and were highly correlated with maternal data, suggesting a regulatory link between both thyroid economies. The results suggested that the common regulatory link is the limited availability of the iodine supply. In conclusion, the present study demonstrates that even in conditions with a marginally low iodine intake, pregnancy constitutes a stimulus for both the maternal and newborn thyroids. Changes in both groups are associated and the abnormalities in TSH and TG are amplified in the newborns. The TSH and TG alterations at birth in full-term healthy newborns, associated with similar alterations in maternal thyroid function, provide evidence for a common stimulatory factor, relative iodine deficiency. The data emphasize the hypersensitivity of neonatal thyroid function to marginal iodine deficiency and point to the need to increase the iodine supply in groups at risk, such as women during pregnancy, and also newborns in the perinatal period.     

Can neonatal TSH screening reflect trends in population iodine intake?

BACKGROUND: The distribution of neonatal blood thyroid-stimulating hormone (TSH) concentrations has been used as an index reflecting population dietary iodine intake, with higher concentrations being indicative of lower iodine intake. We examined this distribution in neonates born in Ireland, where the pregnant population has shown a recent decline in urinary iodine (UI) excretion. Our objectives were to determine if any alteration was observed in the percentage of values > 5.0 mIU/L and whether a trend in neonatal blood TSH was apparent. METHODS: Samples drawn from the National Neonatal Screening Programme were assessed during the years 1995-2006 from winter (January n = 35,079) and summer (August n = 37,940) months, respectively, in view of the known seasonal variation in Irish dietary iodine intake. RESULTS: Apart from the first years studied (1995-1996), the proportion of individual blood TSH values >5.0 mIU/L did not exceed 3%, a value believed to be indicative of iodine deficiency. A significant declining trend in the proportion of blood TSH >5.0 mIU/L was observed in subsequent years (p < 0.01). While excluding severe iodine deficiency, these analyses failed to detect the slight but highly significant (p < 0.001) tendency toward increasing blood TSH within the 0-5.0 mIU/L interval in the study population between 1999 and 2006, which was greater in summer than in winter months (p < 0.001). CONCLUSIONS: These data support a link between fetal thyroid function and a fall in maternal iodine intake. While the findings of the proportion of blood TSH values >5.0 mIU/L exclude severe maternal or fetal iodine deficiency, a trend toward increasing TSH may provide an early indication of impending iodine deficiency. The findings assume greater importance in the context of declining UI reported from many developed countries even where the proportion of blood TSH values >5.0 mIU/L is <3%, thus excluding severe maternal and fetal iodine deficiency.     

Neonatal thyrotropin as measured in a congenital hypothyroidism screening program: influence of the mode of delivery

CONTEXT: Many developed countries are reexperiencing iodine deficiency. One World Health Organization index of iodine deficiency in populations is the percentage of neonates with TSH levels greater than 5 mIU/liter 72 h after delivery. Measured TSH levels vary with methodology and are influenced by external factors including iodine exposure at time of delivery. OBJECTIVE: We wished to determine whether babies delivered by cesarean section have higher levels of TSH than babies delivered vaginally because this factor could influence determination of iodine deficiency. DESIGN AND SETTING: This was a cohort study of mothers delivering at a teaching hospital in 2002-2003 and their babies. PATIENTS AND METHODS: Women delivering a live infant were eligible for the study. Demographic data, mode of delivery, and subsequent routine newborn screening TSH levels were recorded. RESULTS: Of 2031 infants, 31.2% were delivered by cesarean section; 1864 babies were born after 37 wk, with blood samples collected by d 5 (>91% on d 3). Significant predictors of TSH concentration were the day TSH was measured and type of delivery. The distribution curve of TSH values was right shifted in infants born by cesarean section. The percentage of neonates born by cesarean with at TSH value greater than 5 was 7.1%. The figure for those born vaginally was 4.3%. CONCLUSIONS: Babies delivered by cesarean section are significantly more likely to have TSH levels greater than 5 mIU/liter on d 3 than those delivered vaginally. With the rise in the rate of births by cesarean, this could be an important factor in assessing population iodine deficiency using neonatal TSH levels.     

Maternal and Neonatal Urinary Iodine Status and its Effect on Neonatal TSH Levels in a Mildly Iodine-Deficient Area

Objective: Iodine deficiency and excess are the most important factors that affect screening and recall rates of congenital hypothyroidism. The purpose of this study was to investigate the urinary iodine status in newborns and their mothers and its effects on neonatal thyroid-stimulating hormone (TSH) levels in a mildly iodine-deficient area.Methods: A total of 116 newborns and their mothers were included in the study. Urinary iodine levels were measured from healthy mothers and their babies on the 5th day following birth. Neonatal TSH levels were screened, and TSH and free thyroxine (fT4) levels were measured on the15th day in the recall cases. T4 treatment was started in infants with high TSH and low fT4 levels. These measurements were repeated on the 30th day in these newborns.Results: Ninety-nine percent of the mothers included in the study were using iodized salt. The median urinary iodine level in the newborns was 279 µg/L, while it was 84 µg/L in their mothers. The rate of iodine deficiency among the mothers was 56.8%, and the rate of iodine excess was 8.6%. This rate was 10.3% for iodine deficiency and 61.2% for iodine excess in the newborns. The recall rate at the screening was 9.5% (n=11). The urinary iodine levels were above 200 µg/L in three newborns who had transient hyperthyrotropinemia.Conclusions: Iodine deficiency was more frequently observed in nursing mothers, and iodine excess was more frequently seen in their newborns. The iodine excess noted in the newborns was attributed to the use of antiseptics containing iodine. The iodine excess leads to increases in recall rates, screening costs, and frequency of transient hyperthyrotropinemia.Conflict of interest:None declared.     

新生儿TSH测定与成人尿碘测定的对比

本文报道了用纸片法测定沈阳碘缺乏病区新生儿 TSH6498人,结果显示亚临床甲低人群占11.9%,与尿碘测定显示结果12.0%是一致的。进一步比较各县区新生儿 TSH 值与成人尿碘值,发现二者之间成高度负相关,且有较好的直线回归关系。笔者对两种测定方法做了简单对比,认为新生儿纸片TSH 测定是碘缺乏病监测的可靠指标,建议在我国逐步推广应用。