Reference values for blood levels of free thyroxine, free triiodothyronine and thyroxine-binding globulins in euthyroid children. Method: luminescence-enhanced enzyme immunoassay

Concentrations of free thyroxine (n = 296, male 164, female = 132), free triiodothyronine (n = 273, male 156, female = 117) and thyroxine-binding globulin (n = 273, male 156, female = 117) were determined using the luminescence enhanced enzyme immunoassay method in blood-serum of euthyroid children. Beyond the 30, day of life no significant differences were found in different age groups for the free thyroxine and beyond the 2, day of life for the free triiodothyronine concentration. The free thyroxine values of the infants in the range of 15-39 pg/ml decreased to the range of 9-18.5 pg/ml and the free triiodothyronine values decreased from 3.4-9.3 pg/ml to the range of 2.8-6.5 pg/ml. The values for thyroxine-binding globulin increased in the first month of life up to the range of 18-35 mg/l and decreased afterwards continuously to the range of 14.5-26.5 mg/l.     

Reference values for the concentrations of triiodothyronine, thyroxine and thyrotropin in the blood serum of euthyroid children. Method: luminescence-enhanced enzyme immunoassay

Concentrations of triiodothyronine, thyroxine and thyrotropin were determined using the luminescence enhanced enzyme immunoassay method in blood serum of 343 (male = 197, female = 146) euthyroid children. Beyond the newborn age no significant difference was found for the thyrotropin concentration. Compilation of the values resulted in a physiological thyrotropin concentration of 1.73 +/- 0.81 (1s) microU/ml for infants, children and juveniles. In opposition to these results the thyroxine and triiodothyronine concentration showed an age-specific dependence. The thyroxine and triiodothyronine concentrations (means +/- 1s) decreased continuously from the infant age (TT4: 182.1 +/- 37.7 ng/ml, 234.9 +/- 48.6 nmol/l, TT3: 1.77 +/- 0.57 ng/ml, 2.73 +/- 0.88 nmol/l) to the juvenile age (TT4: 77.9 +/- 14.3 ng/ml, 100.5 +/- 18.4 nmol/l, TT3: 1.25 +/- 0.31 ng/ml, 1.93 +/- 0.48 nmol/l). The luminescence enhanced enzyme immunoassay technique is suitable for use in the routine thyroid laboratory.     

Reference values for the concentration of free thyroxine and free triiodothyronine in the serum of euthyroid children

Concentrations of free thyroxine (n = 341, male = 205, female = 136) and free triiodothyronine (n = 318, male = 198, female = 120) were determined using the radioimmunoassay method in blood serum of euthyroid children. Beyond the 30. day of life no significant differences were found in different age groups for the free thyroxine and free triiodothyronine concentration. The free thyroxine values of the infants in the range of 16.5-19.5 pg/ml decreased after the 30. day of life to the range of 15-17.5 pg/ml. In opposition to this trend free triiodothyronine values increased after the 30. day of life from the range of 2.5-3.3 pg/ml up to the range of 4.7-5.5 pg/ml.     

Reference values for the concentration of free triiodothyronine (FT3), triiodothyronine (TT3), free thyroxine (FT4), thyroxine (TT4), thyrotropin (TSH) and thyroxine-binding globulin (TBG) in umbilical cord blood. Method: luminescence-enhanced enzyme immunoassay]

Physiological concentrations of FT3, TT3, FT4, TT4, TSH and TBG were determined using the luminescence enhanced enzyme immunoassay method in cord blood serum (n = 100). The results are presented in Table 1.     

Transient secondary hypothyroidism and thyroxine binding globulin deficiency in leukemic children during polychemotherapy: An effect of L-asparaginase

Recently it has been observed that L-asparaginase causes transient thyroxine binding globulin (TBG) deficiency in adults. In the present study we investigated the influence of L-asparaginase on the pituitary-thyroid axis and on the synthesis of TBG. 14 children with acute lymphoblastic leukemia were treated with a combination of L-asparaginase, vincristine, prednisone and daunomycin for remission induction. Thyroid function was monitored by measuring total T₄, free T₄, total T₃, TSH and TBG with specific radioimmunoassays before, during and after treatment. Within 3 weeks of L-asparaginase therapy total T₄ fell significantly from 10.7±1.6 to 2.9±1.8 g/100 ml, free T₄ from 1.77±0.4 to 0.94±0.35 ng/100 ml, total T₃ from 0.99±0.23 to 0.35±0.2 ng/ml and TBG from 29.4±3.6 to 8.0±3.8 g/ml. Basal TSH values tinuation of L-asparaginase, but following further treatment with other antileukemic agents, all values became normal within 2–4 weeks. In 6 patients with hypothyroid free T₄ values TRH induced TSH release was totally blocked during L-asparaginase therapy. Our data clearly demonstrated that L-asparaginase caused a transient TBG deficiency. Total T₄ and T₃ were in the hypothyroid range because of low TBG concentrations. In addition to TBG deficiency transient, secondary hypothyroidism occurred in approximately 40–50% of all patients treated with L-asparaginase. These alterations were most likely caused by drug induced inhibition of protein synthesis. Under certain circumstances thyroid hormone replacement might be life-saving in severely ill patients suffering from transient, drug induced hypothyroidism.Presented in part at the 19th Meeting of the European Society for Pediatric Endocrinology, August 31–September 3, 1980, Bergamo/Italy     

Behavior of the levels of free triiodothyronine, triiodothyronine, free thyroxine, thyroxine, thyrotropin and thyroxine-binding globulin in the serum of children with nephrotic syndrome

Concentrations of free triiodothyronine, triiodothyronine, free thyroxine, thyroxine, thyrotropin, thyroxine-binding globulin, urea, creatinine, cholesterol and total protein were determined in serum of four children (ages from 8 to 16 years) with nephrotic syndrome undergoing therapy. The results showed that at serum protein concentration of less than 4.5 g/dl the concentration of free thyroxine was 3.35 +/- 2.32 pg/ml and that of free triiodothyronine 2.65 +/- 0.96 pg/ml. Elevation of the protein concentration to 4.5-5.7 g/dl lead to an increase in the concentration of free thyroxine to 6.53 +/- 3.69 pg/ml and of free triiodothyronine to 3.32 +/- 1.08 pg/ml. The age-matched reference values for free thyroxine are 15.72 +/- 1.9 pg/ml and for free triiodothyronine 5.10 +/- 1.29 pg/ml. The concentration of thyroxine, triiodothyronine and thyroxine-binding globulin were decreased whereas that of thyrotropin was elevated. Although free triiodothyronine and triiodothyronine were decreased they remained close to the normal range thus preventing apparent hypothyroidism. Improvement in the concentration of serum protein and cholesterol lead to an improvement of serum levels of thyroid hormones and thyroxine-binding globulin; concentrations of thyrotropin remained elevated.     

Waist circumference and waist-to-height ratio in Norwegian children 4-18 years of age: reference values and cut-off levels

Aim: To establish reference values for waist circumference and waist‐to‐height ratio of Norwegian children. Material: Data were collected in 2003–2006 as part of a cross‐sectional study, including 5725 children 4–18 years of age. Reference curves were fitted with the LMS method; appropriate cut‐offs were selected using receiver operating characteristic analysis. Results: Reference values for waist circumference and waist‐to‐height ratio are presented. Mean waist circumference increased with age for both genders. Boys had a higher waist circumference at almost all ages. Mean waist‐to‐height ratio decreased until early adolescence and thereafter increased slightly towards adult age. There was a strong positive correlation between waist circumference and BMI (r = 0.907, p < 0.01) and a moderate positive correlation between waist‐to‐height ratio and BMI (r = 0.397 p < 0.01). A waist circumference cut‐off value of 1.0 SDS (85th percentile) gave a sensitivity of 79% and a specificity of 94% to detect overweight. A cut‐off value of 1.6 SDS (95th percentile) gave a sensitivity of 94% and a specificity of 96% to detect obesity. Conclusion: This study presents the first reference values of waist circumference and waist‐to‐height ratio for Norwegian children 4–18 years, which also represent the first reference in Scandinavian schoolchildren. The 85th and 95th percentiles of waist circumference are proposed as appropriate cut‐offs for central overweight and obesity.     

Serum thyroxine and thyroid stimulating hormone values in unreferred children with short stature.

Of 449 children aged 6-9 years with heights below the first centile in a total population of 48 221, only 1 had previously undiagnosed hypothyroidism. In a community with well developed health services hypothyroidism is unlikely to be the cause of short stature among primary school children.     

磁共振弥散加权成像及表观弥散系数在儿童脑梗死中的诊断价值

目的探讨磁共振弥散加权成像（diffusionweightedmagneticresonanceimaging,DWI）及表观弥散系数（apparent diffusion coefficient,ADC）在脑梗死不同时期诊断及判断脑梗死转归中的价值。方法对26例患儿按发病就诊时间分为l期（0—72h）11例次,Ⅱ期（4-10d）12例次,Ⅲ期（10d以后）9例次,其中3例为复查,3例为复发脑梗死,共计29例次。对每例患儿进行MRI的T1加权像、配加权像、DWI序列扫描检查及ADC图像重建,于ADC图上取1个感兴趣区（regionsofinterest,ROI）,计算出ROI的平均ADC值,同样的方法计算出镜像健侧相对应区的平均ADC值,并计算平均相对ADC值。结果DWI图像改变I期全部病例均呈现高信号;Ⅱ期11例次呈现高信号,1例次为低信号;Ⅲ期1例次为正常信号,1例次为高信号,2例次为混杂信号,1例次较前减低,其余均为低信号。在I期患儿ROI平均ADC值较对侧相应区域平均ADC值均下降,随着时间的发展Ⅱ期、Ⅲ期平均ADC值逐渐升高,梗死灶I期、Ⅱ期、Ⅲ期平均ADC值分别为0．434×10^-3mm2／s、0．653×10^-3mm2／s、1．600×10^-3mm2／s,对侧相应区域平均ADC值分别为0．938×10^-3mm2／s、0．814×10^-3mm2／s、0．757×10^-3mm2／s;Ⅰ期、Ⅱ期、Ⅲ期相对ADC平均值随着时间发展逐渐升高,分别为（51．5±16．8）％、（79．2±30．0）％、（210．9±45．1）％,差异均有统计学意义（P均〈0．05）。结论弥散加权MRI及ADC平均值对脑梗死早期诊断具有重要价值;脑梗死病灶ADC值和相对ADC值在时间上的变化规律为准确地判断脑梗死时期提供客观依据;弥散加权MRI及ADC平均值能为临床治疗及判断预后提供有效手段。     

西藏地区2～14岁藏族儿童血常规和血清铁参考值的建立

目的建立西藏地区藏族2~14岁儿童血常规和血清铁参考值。方法在西藏拉萨市选取西藏自治区人民医院妇幼保健院(我院)儿童保健科作为学龄前儿童数据采集现场,选取西藏自治区江孜县和隆子县3所小学作为学龄儿童数据采集现场,藏族儿童是指父母均为藏族、且世代居住在藏区;行体格检查时采集的儿童的静脉血,统一在我院临床检验科行血常规和血清铁检测,检验值直接从相关仪器导出用于本文分析。依据检测指标分布特点,采用百分位数法(P2.5~P97.5)或x±1.96 s确定其双侧参考值范围,采用LMS program软件(版本:1.35),拟合血常规和血清铁依年龄变化的百分位数曲线。结果 2016年1月1日至12月31日2~14岁3 881(藏族3 137和汉族744)名健康儿童进入本文分析。学龄前儿童血标本3 253份,学龄儿童血标本628份。2~6岁组分别为546、1 878、475、270和111例,7~14岁组36~101例,藏、汉族儿童不同年龄段性别差异均无统计学意义(P均0.05)。较平原地区RBC、Hb和PLT参考值范围整体右移,运铁蛋白饱和度(UIBC)、血清总铁结合力(TIBC)参考值范围更宽;WBC参考值范围左移,中性粒细胞计数(NEUT#)、淋巴细胞计数(LYMPH#)、单核细胞计数(MONO#)和嗜酸性粒细胞百分比(EO%)参考值范围更宽,嗜碱性粒细胞百分比(BASO%)参考值范围稍小。就绝对计数来看,NEUT#参考值范围左移,LYMPH#、MONO#、嗜酸性粒细胞计数(EO#)和BASO#参考值范围更窄。Hb、RBC比容(HCT)、平均PLT容积(MPV)、RBC平均Hb量、浓度和体积(MCH、MCHC和MCV)和RBC分布宽度(RDW-SD)随年龄呈上升趋势,PLT、淋巴细胞百分比(LYMPH%)和BASO%随年龄呈下降趋势,中性粒细胞百分比(NEUT%),PLT比容(PCT)随年龄增长先升后降。除TIBC、MCH和PCT外,余指标在藏族与汉族儿童中差异均有统计学意义。其中,汉族儿童WBC、RBC、血清铁、Hb、HCT、PLT和MCV水平高于藏族儿童;藏族儿童MCHC、RDW-CV、PLT分布宽度(PDW)、UIBC、MPV和RDW-SD水平高于汉族儿童。结论与平原地区比较,西藏高海拔地区血常规和血清铁参考值随儿童年龄的变化趋势与平原在区基本一致,RBC、Hb和PLT等参考值范围整体右移且范围更宽,WBC及其分属参考值范围左移且范围更宽,西藏高海拔地区血常规和血清铁应以当地参考值作为参照。     

LDH-isoenzymes in children. A comparison of values from capillary and venous blood.

A comparison has been made of serum values of LDH-isoenzymes obtained by simultaneous sampling of capillary and venous blood in 40 normal children. No satisfactory correlation between the paired values could be found. Evaluation of the pattern of serum LDH-isoenzymes in children therefore requires a reference, i.e. normal values of isoenzymes obtained by the same technique of blood sampling.     

Normal values for free thyroxine, free triiodothyronine, reverse triiodothyronine, thyrotropin, thyroglobulin and thyroxine-binding globulin in umbilical cord blood of healthy mature newborn infants

The venous cord blood levels of free thyroxine (fT4), free triiodothyronine (fT3), reverse triiodothyronine (rT3), thyrotropin (TSH), thyroglobulin (TG) and thyroxine binding globulin (TBG) were studied in 56 mature and healthy newborns. Newborns with a gestational age less than 37 or more than 42 weeks, a delivery by forceps or cesarian section, a birth-weight less than 2500 g, a pH-value of the cord-artery blood less than 7.15, an Apgar-value after 1 minute less than 7 were excluded from the study. All mothers were non-smokers. The values of fT4 were 18.66 +/- 4.18 pmol/L, of fT3 were 1.59 +/- 0.75 pmol/L, of fT3 were 2152 +/- 666 pg/ml, of TSH were 7.83 +/- 4.49 mU/ml, of TG were 44.61 +/- 23.84 ng/ml, and of TBG were 25.61 +/- 5.42 micrograms/ml. A weak negative correlation was found between the TG-value and the pH-value of the cord-artery blood (r = -0.27, y = 191.55 - 22.82.x, p less than 0.05), and between the fT4 values and the gestational age (r = -0.34, y = 67.53-1.22.x, p = 0.01). The rT3-values were positively correlated to the gestational age (r = 0.29, y = -4571 + 167.x, p less than 0.03).     

1002例4岁以下小儿潮气呼吸流速-容量环正常值的研究

目的测定健康小儿潮气呼吸肺功能正常值。方法用潮气呼吸方法测定1002例1~47个月小儿流速-容量曲线并计算其衍生参数。结果流速-容量环在健康婴幼儿呈不典型椭圆型,随年龄增长渐趋光滑。4岁以下小儿各项肺功能测定值主要与身高、体重、月龄相关,以前两者尤其是身高关系更为明显。有关参数显示小儿肺容量的增加大于流速的增长,小气道的发育快于大气道,代谢率随着年龄的增长而降低,达峰时间比(TPTEF/TE),达峰容积比(VPEF/VE)在各年龄组间差异存在,其数值的变化可反映小气道的阻塞情况。结论小儿肺功能与身高、体重、月龄相关,尤与身高相关更为显著;潮气呼吸肺功能测定简便、准确、重复性好,可作为4岁以下小儿检测肺功能的首选。     

Normal values for circulating thyroid hormones, T3 uptake and thyrotropin before and after TRH. Radioimmunoassay determinations on 182 euthyroid children (author's transl)

Measurements of T4, T3, rT3, T3U, and TSH (before and after TRH stimulation) were performed by RIA. 182 children, apparently euthyroid, age 2/12--14 years, were investigated in a cross sectional study. Free T4RIA and free T3RIA Indices and the ratio rT3/T3 and T4/T3 were calculated. Statistical analysis showed the following results: 1. Geometric mean serum concentrations of T4, T3, rT3 and TSH (basal) show no age related differences; T4 showed a not significant negative slope with age.--2. The ratio rT3/T3 and T4/T3 remains constant.--3. TRH induced TSH release (indicating the activity of the regulatory system) is unchanged from 2/12 to 14 years. Geometric means values, standard deviations and normal ranges are given.     

Comparison of six-minute walk test in children with moderate/severe asthma with reference values for healthy children

Objectiveto compare physical performance and cardiorespiratory responses in the six-minute walk test (6MWT) in asthmatic children with reference values for healthy children in the same age group, and to correlate them with intervening variables.Methodsthis was a cross-sectional, prospective study that evaluated children with moderate/severe asthma, aged between 6 and 16 years, in outpatient follow-up. Demographic and spirometric test data were collected. All patients answered the pediatric asthma quality of life (QoL) questionnaire (PAQLQ) and level of basal physical activity. The 6MWT was performed, following the American Thoracic Society recommendations. Comparison of means was performed using Student's t-test and Pearson's correlation to analyze the 6MWT with study variables. The significance level was set at 5%.Results40 children with moderate or severe asthma were included, 52.5% males, 70% with normal weight and sedentary. Mean age was 11.3 ± 2.1 years, mean height was 1.5 ± 0.1 m, and mean weight was 40.8 ± 12.6 Kg. The mean distance walked in the 6MWT was significantly lower, corresponding to 71.9% ± 19.7% of predicted values; sedentary children had the worst values. The difference between the distance walked on the test and the predicted values showed positive correlation with age (r = 0.373, p = 0.018) and negative correlation with cardiac rate at the end of the test (r = -0.518, p < 0.001). Regarding QoL assessment, the values in the question about physical activity limitations showed the worst scores, with a negative correlation with walked distance difference (r = -0.311, p = 0.051).Conclusionsasthmatic children's performance in the 6MWT evaluated through distance walked is significantly lower than the predicted values for healthy children of the same age, and is directly influenced by sedentary life style.