经皮测量总胆红素在新生儿高胆红素血症评估中的应用价值

目的探讨经皮测量胆红素浓度对新生儿黄疸检测的准确性和实用性。方法对400例高胆红素血症新生儿同时进行了经皮测量总胆红素和血清总胆红素的检测,分析两者的相关性,并评估体质量、胎龄、生后日龄、相关病因等对新生儿胆红素水平的影响。结果血清总胆红素<257μmol/L时,经皮测量总胆红素与血清总胆红素值的相关系数是0.932,血清总胆红素≥257μmol/L时,相关系数是0.282,两组均呈正相关性,血清总胆红素<257μmol/L组相关性高(P=0.0001),且不受胎龄、体质量、生后日龄及相关病因的影响。结论当胆红素浓度<257μmol/L,经皮测量总胆红素可以替代血清总胆红素;经皮测量总胆红素用于新生儿高胆的筛查,有可推广性及实用性。     

脐血胆红素预测新生儿黄疸的意义

目的研究脐带血胆红素水平预测足月健康新生儿后续黄疸程度的价值。方法523例足月健康新生儿,测定脐血胆红素、白蛋白水平,监测每日经皮胆红素值（TCB）。对时龄0—24hTCB≥18;-48hTCB≥21;-72hTCB≥25;〉72h≥25者,送检静脉血血清胆红素值（TSB）,考虑是否需要光疗。将新生儿按脐血胆红素水平分为〈30μmol／L;≥30μmoL／L;≥36μmol／L;≥42μmoL／L,共4组。比较4组新生儿TCB≥25、TSB〉205μmol／L、TSB〉257μmoL／L及需要光疗的发生率。对脐血胆红素水平预告新生儿黄疸进行分析。比较黄疸组新生儿和非黄疸组新生儿临床特征。结果脐血胆红素水平升高,各组新生儿TCB≥25、TSB〉205μmol／L、TSB〉257μmoL／L和需要光疗的发生率增加。脐血胆红素水平用于预测新生儿黄疸发生有统计学意义（P〈0．001）。黄疸组新生儿脐血胆红素值显著高于非黄疸组（t=10．96,P〈0．001）。而脐血清白蛋白值（t=2．38,P〉0．05）、妊娠周数（t=-0．90,P〉0．05）、出生体重（t=0．10,P〉0．05）比较,两组均无统计学差异。结论脐血胆红素水平用于预测足月健康新生儿后续黄疸的程度是一种有效的方法。     

Transcutaneous bilirubinometry in preterm infants

The aim of this study was to evaluate the accuracy and safety of transcutaneous bilirubinometry in preterm infants using the new bilirubin analyser BiliCheck^±. The study included 145 preterm children (23–36 wk gestation). Capillary blood sampling for determination of serum bilirubin (BS) was combined with transcutaneous bilirubin measurement (BTc) every morning until the sixth postnatal day and related to several clinical data (phototherapy (PT), infection signs, breathing disturbances, skin bleeding, etc.). Overall bilirubin concentration ranged from 17 to 371 μmol/l, and from 21 to 325 μmol/l for BS and BTc, respectively. Mean values obtained by BTc were significantly higher than BS values. The correlation coefficient between BS and BTc was r= 0.64 for the whole group, and r= 0.73 in infants without PT. As demonstrated by multiple regression analysis, BS‐BTc correlations were related only to gestational age (beta ‐0.32) and breathing disturbances (beta 0.29), indicating that the lower the gestational age and the more seriously ill the baby, the higher the incoherence between BS and BTc. Conclusion: BiliCheck^±provides a convenient, non‐invasive possibility for bilirubin estimation in preterm infants. However, there are limitations: the method gives reliable results only in newborns older than 30 wk gestation, without PT and artificial ventilation.     

普瑞博思辅助治疗新生儿高胆红素血症疗效观察

目的　观察普瑞博思对新生儿高胆红素血症的治疗作用。方法　８９ 例新生儿高胆红素血症患儿随机分为对照组和治疗组,治疗组在常规治疗的同时,加用普瑞博思混悬液０．２ ｍｇ／ｋｇ,每日３ 次口服,共７ ｄ。治疗前后分别监测血清胆红素水平。结果　治疗组胆红素日均下降值为５３．１８±２６ ．３８ μｍｏｌ／Ｌ,明显高于对照组的３５ ．８６±２ ．３６ μｍｏｌ／Ｌ（ Ｐ＜ ０．０１）。结论　普瑞博思用于治疗新生儿黄疸,可加速降低胆红素水平,明显缩短治疗时间。     

Early neonatal hyperbilirubinemia using first day serum bilirubin level

OBJECTIVE: To evaluate the predictive value of total serum bilirubin (TSB) < or =6 mg/dl at 24 +/- 6 hr postnatal age in identifying near term and term infants, who do not develop hyperbilirubinemia subsequently. DESIGN: Prospective study. SETTING: Tertiary care hospital. METHODS: All healthy neonates with gestation > or =35 weeks, in absence of significant illness or Rh hemolysis were included. TSB was estimated at 24 +/- 6 hr by micromethod using spectrophotometry. Infants were followed up clinically every 12 hr till discharge and then after 48 hr. TSB level was estimated again whenever clinical suspicion of jaundice exceeded 10 mg/dl. Primary outcome was defined as presence of hyperbilirubinemia (TSB > or= 17 mg/dl) till day five of age. RESULTS: Of the 220 infants, 213 (96.8%) were followed up. All infants were exclusively breastfed. Mean age at bilirubin estimation was 24.7 +/- 1.9 hr with mean TSB of 5.9 +/- 1.8 mg/dl. Clinically detectable jaundice was present in 164 (77%) and hyperbilirubinemia occurred in 22 (10.3%) infants. A TSB level of < or = 6 mg/dl at 24 +/- 6 hr was present in 136 (63.8%) infants and only one infant developed hyperbilirubinemia subsequently (probability < 1%). In the remaining 77 (36.1%) infants, with TSB >6 mg/dl, subsequent hyperbilirubinemia developed in 21 (27.2%) (sensitivity 95%, specificity 70.6%, positive predictive value 27.2%, negative predictive value 99.3%, likelihood ratio of positive test 3.23 and likelihood ratio of negative test 0.07). Babies with TSB levels higher than 6 mg/dl had a significant risk of developing hyperbilirubinemia (relative risk 38; 95% confidence interval 6-1675). CONCLUSION: A TSB level of < or = 6 mg/dl at 24 +/- 6 hr of life predicted neonates who would not develop hyperbilirubinemia.     

Efficacy of phototherapy for hyperbilirubinaemia in infants with the respiratory distress syndrome

Objectives: To evaluate the efficacy of phototherapy for hyperbilirubinaemia in preterm infants with and without the respiratory distress syndrome (RDS).
Methodology: Prospective cohort study of preterm infants cared for at Kandang Kerbau Hospital, Singapore: 170 with RDS and 477 without RDS, sepsis or other complications (control group) presenting with non-haemolytic hyperbilirubinaemia at about the same time were exposed to daylight phototherapy when bilirubin concentrations exceeded 255 μmol/L or 222 μmol/L if <48h of age. Bilirubin values were monitored 6-hourly during exposure, and daily for at least 2 days postphototherapy.
Results The infants were comparable in birthweight, gestational age, postnatal age, haemoglobin, haematocrit and bilirubin values, at start. The response to phototherapy of the infants with RDS was comparable to that of the well preterm infants; the duration of exposure was 50.1 ± 1.6 (mean ± s.e.m.) versus 50.1 ± 1.4 h, 24-hour decline rate 25.71 ± 1.29% versus 26.32 ± 0.65, and overall decline rate 0.96± 0.03%/h versus 0.95±0.02%/h.
Conclusion The presence of RDS did not affect the efficacy of phototherapy for neonatal hyperbilirubinaemia in preterm infants.     

Urinary malondialdehyde concentration in preterm neonates: is there a relationship to disease entities of neonatal intensive care?

In a retrospective study, urinary malondialdehyde concentration in 45 preterm neonates (25–35 weeks' gestation) during their first month of life was measured by HPLC. Urine was collected on different days of life as a 3-h sample. The frequency of urine collection and measurement varied between one (n = 22) and seven times (n = 8) per child. The study group was divided into three categories according to birth weight: low-birth-weight infants (LBW) (n= 16), very low-birth-weight infants (VLBW) (n = 17) and extremely low-birth-weight infants (ELBW) (n=12). Urinary malondialdehyde concentration was highest in the ELBW group: 1.15 (0.66, 2.12) μmol/l (median and quartiles) versus 0.58 (0.34, 1.18) μmol/l in the VLBW and 0.60 (0.40, 1.06) μmol/l in the LBW groups (ELBW versus VLBW, p < 0.005; ELBW versus LBW, p<0.02). In oxygen-treated neonates, significantly higher malondialdehyde values were found compared to those without supplementary oxygen (0.89 (0.48, 1.74) versus 0.58 (0.32, 0.89) μmol/l; p < 0.005). Likewise, a higher malondialdehyde concentration was found in infants requiring mechanical ventilation (intermittent mandatory IMV or high frequency ventilation) compared to those breathing spontaneously (intermittent mandatory ventilation: 0.80 (0.42, 1.66); p < 0.05 and high frequency ventilation: 1.20 (0.83, 2.13); p < 0.001 versus 0.57 (0.33, 0.88) μmol/l). Malondialdehyde concentrations correlated significantly with FiO₂ yalues of the individual patients (r = 0.22; p<0.02). Comparing urinary malondialdehyde concentrations in infants with and without bronchopulmonary dysplasia, a significantly higher malondialdehyde concentration was found in the former group (0.96 (0.51, 2.07) versus 0.60 (0.32, 0.98) μmol/l;p<0.005)). Infants with patent ductus arteriosus had a higher urinary malondialdehyde concentration than those without patent ductus arteriosus (1.04 (0.58, 3.78) versus 0.64 (0.36,1.20) μmol/l;p 0.05)). Malondialdehyde concentrations were also higher in infants with intracranial bleeding compared to those without (0.83 (0.46, 1.42) versus 0.56 (0.33, 1.10) μmol/l; p<0.02)). No significant differences in urinary malondialdehyde concentration were seen, either in relation to i v feeding with or without lipid emulsion or to medication administered. Native malondialdehyde concentration in seven commercial preparations of lipid emulsion after various periods of storage was fairly constant (12.3 ± 0.4 μmol/l) (mean ± SD).     

Accuracy of neonatal transcutaneous bilirubin measurement in the outpatient setting

OBJECTIVE. To evaluate the effectiveness of transcutaneous bilirubin (TcB) measurement in predicting risk for neonatal hyperbilirubinemia in outpatients. DESIGN. Subjects were infants ≤8 days old seen in an outpatient clinic. Infants discharged with high-risk (HR) or high-intermediate risk (HIR) total serum bilirubin (TSB) values and jaundiced infants were recruited. TSB and TcB (BiliChek) levels were plotted on an hour-specific nomogram to determine risk for hyperbilirubinemia. RESULTS. A total of 79 infants provided 87 sets of TcB and TsB values. Mean bias and standard deviation between TcB and TsB was 1.5 ± 2.1 mg/dL for outpatients, compared with 2.7 ± 1.3 mg/dL for inpatients. The sensitivity and specificity of HR or HIR TcB for predicting an HR or HIR TSB were 87% and 58%, respectively. Of 9 infants readmitted for phototherapy, 1 had a low-risk TcB and high-risk TSB. CONCLUSIONS. TcB screening in the outpatient environment may not be safe and efficient.     

Transcutaneous bilirubin measurement at the time of hospital discharge in a multiethnic newborn population

BACKGROUND:

Severe neonatal hyperbilirubinemia continues to occur in healthy newborns. Recent guidelines have supported using transcutaneous devices in estimating bilirubin levels. Previous studies using these devices are limited.

METHODS:

Newborns requiring serum bilirubin level measurements before hospital discharge were recruited prospectively. The agreement between a transcutaneous bilirubin (TCB) and total serum bilirubin (TSB) level was assessed. Sensitivity analysis was conducted.

RESULTS:

A total of 430 infants were enrolled. Correlation between the values was high (Pearson’s correlation coefficient 0.83; Lin’s concordance coefficient 0.81 [95% CI 0.77 to 0.84]; P<0.001). The mean (± SD) TSB level was 194±60 μmol/L. The TCB measurement tended to overestimate the value (mean difference 12.7), with wide 95% limits of agreement (−52 μmol/L to 77 μmol/L). Sensitivity and specificity analysis of TCB values allowed estimation of clinically important TSB levels.

CONCLUSIONS:

The TCB correlated, but was imprecise in predicting TSB. TCB values can be used at the time of discharge to safely plan care for jaundiced infants if the limits of agreement are considered and clinical judgment is maintained.     

Relation between serum bilirubin levels ≥450 μmol/L and bilirubin encephalopathy; a Danish population-based study

Aim: Describe the relation between levels of total serum bilirubin (TsB) ≥450 μmol/L and acute intermediate, acute advanced and chronic bilirubin encephalopathy. Material and methods: All infants born at gestational age ≥35 weeks in Denmark between 2000 and 2007 with a TsB ≥450 μmol/L according to the national laboratory information system. Infants diagnosed with bilirubin encephalopathy were found in the Danish National Registry of Patients. Results: 502 766 infants at gestational age ≥35 weeks were identified. Two hundred twenty‐four developed a TsB ≥450 μmol/L, equivalent to an incidence of 45/100 000/year, and it increased during the period. Incidence of infants with peak TsB of 450–499, 500–599 and 600–1000 μmol/L were 29.6, 12.7 and 2.2 per 100 000, respectively. Three infants had acute advanced bilirubin encephalopathy and got severe sequelae, whereas the two infants with acute intermediate encephalopathy developed normally. Their peak TsB was ≥544 μmol/L. Having a peak TsB 600–1000 μmol/L, the risk of acute advanced and chronic bilirubin encephalopathy was 27% (95% CI 6;61), and the incidence of these conditions was 0.6 (95% CI 0.1;1.7) per 100 000. Conclusion: The incidence of infants with TsB ≥450 μmol/L was 45/100 000/year. Infants with a TsB ≥600 μmol/L had a substantial risk of developing acute advanced and chronic bilirubin encephalopathy, and the incidence of these conditions was 0.6 per 100 000.     

新生儿小时胆红素百分位曲线图的制备及早期预测高胆红素血症的初步探讨

目的绘制新生儿胆红素百分位曲线图预测新生儿高胆红素血症的发生风险。方法选择2009年1~9月南京医科大学附属南京妇幼保健院出生的母婴同室和普通婴儿室胎龄≥35周且出生体重≥2 000 g的正常新生儿为研究对象,监测生后7 d经皮胆红素值(TCB),对TCB≥250μmol.L-1者测定微量血胆红素,以所得到的胆红素值数据绘制小时胆红素百分位曲线图。以小时胆红素百分位曲线图将出院前末次胆红素值转换至危险区域(低危:≤P40;中低危:~P75;中高危:~P95;高危:P95)。选取72 h内对应最高危区域的胆红素测定值作为预测指标,采用ROC曲线分析胆红素百分位曲线图对新生儿高胆红素血症的预测价值。结果4 462例新生儿的27 271个对应不同小时龄的胆红素值纳入分析。出院前有5.2%(233/4 462例)的新生儿在生后72 h内的胆红素水平处于高危区,其中48.9%(114/233例)的新生儿在出院后胆红素水平仍处于高危区,预测新生儿发生高胆红素血症的似然比为9.5,敏感度为26.7%,特异度为97.1%,患病率为48.9%;出院前共有23.2%(1 034/4 462例)的新生儿胆红素水平处于高危区和中高危区,预测新生儿发生高胆红素血症的敏感度为78.9%,特异度为82.5%;出院前有41.3%(1 845/4 462例)的新生儿胆红素水平处于低危区,其中无一例在出院后发生高胆红素血症,似然比为0,敏感度为100%,特异度为45.5%,患病率为0。出院前胆红素水平预测高胆红素血症发生风险的ROC曲线下面积(AUC)为0.870。胎龄与出院前胆红素水平相结合预测高胆红素血症发生风险的ROCAUC为0.908。结论用出院前小时胆红素水平预测新生儿高胆红素血症的发生风险是一种有效的方法,结合胎龄可提高预测的准确性。     

重度高胆红素血症新生儿苍白球磁共振成像特征及其临床意义

目的探讨苍白球MRI信号改变与高胆红素血症的严重程度及其相关因素关系,为胆红素脑病诊断与预后判定提供客观依据。方法36例高胆红素血症新生儿（TSB〉342μmoL／L）在生后[10±6（2～34）]d接受头部MRI检查。场强1．5～3．0Tesla,扫描序列为T1WI,T2WI和DWI。2名不知被检者病史的放射科医师分析MRI结果。结果首次MRI有20例苍白球T1WI呈对称性高信号。有苍白球信号改变组的TSB、B／A及UCB均显著高于无改变组[（605．28±89．19）μmoL／L vs．（438．19±67．89）μmoL／L,（1．08±0．18）vs．（0．77±0．16）,（555．49±92．3）μmoL／L vs．（412．01±54．8）μmoL／L,P=0．000],所有MRI-DWI均未见信号改变;TSB在342．0～427．5μmoL／L者9例,未见苍白球信号改变,427．5～513．0μmoL／L者7例,有改变者3例,超过525．0μmoL／L 20例,有改变者17例,黄疸程度与苍白球信号改变有密切关系（χ^2=15．000,P=0．000）;15例ABE苍白球T1WI均呈对称性的高信号（χ^2=17．601,P=0．000）,同时3例T2WI苍白球也呈对称性稍高信号（TSB分别为,745．3μmoL／L,735．7μmoL／L,707．6μmol/L）。7日内入院的25例中,16例苍白球有改变,平均入院时间显著晚于9例无改变者[（121．5±39．9）h vs．（68．9±35）h,P〈0．03]。6例接受了第2次MRI,其中3例ABE有2例苍白球信号转为T2WI高信号,临床均表现脑瘫,另1例苍白球信号正常,但有听力异常;余3例非ABE患儿,2例苍白球信号转为正常,1例两次均无苍白球信号异常,目前发育正常。结论MRI T1WI苍白球对称性高信号,与高胆红素血症的严重程度及暴露时间密切关系,是新生儿ABE的重要表现特征。T1WI高信号转变为T2WI高信号可能提示预后不良。     

高胆红素血症早产儿血清胰岛素样生长因子-1水平的变化及其临床意义

目的 探讨高胆红素血症(高胆)早产儿血清胰岛素样生长因子-1(IGF-1)水平的变化及其临床意义.方法 应用电化学发光免疫法检测64例高胆早产儿(实验组)和20例非高胆早产儿(对照组)血清IGF-1、神经元烯醇化酶(NSE)水平,同步测定其血清总胆红素(TSB)水平,并比较组间IGF-1、NSE、TSB水平的差异及其相关性.高胆组按TSB170～256μmol·L-1,257～342μmol·L-1,＞342μmol ·L-1分为轻、中、重3组.结果 轻、中、重高胆早产儿血清IGF-1水平分别为(25.38±5.42)μg·L-1、(21.77±8.65)μg·L-1、(18.34±4.05)μg·L-1,较对照组[(27.14±3.72)μg·L-1]明显降低,轻、中、重高胆组间IGF-1水平存在统计学差异(Pa＜0.01),其值随着胆红素水平变化而变化;高胆组NSE水平分别为(25.01±2.26)μg·L-1、(30.45±2.74)μg·L-1、(33.76±5.02)μg·L-1,明显高于对照组[(11.14±4.68)μg·L-1](P＜0.01),各组间差异均有统计学意义(Pa＜0.01);血清IGF-1水平与TSB、NSE均呈负相关(r=-0.562、-0.503,Pa＜0.01).结论 IGF-1与高胆早产儿的预后密切相关,可作为判断高胆早产儿是否存在脑损伤的生化指标之一.     

新生儿高胆红素血症与有机阴离子转运体1B1 T521C/A388G多态性的相关性研究

目的 有机阴离子转运体1B1(OATP 1B1)跨膜转运体内非结合胆红素(UCB),其基因变异能显著影响体内胆红素水平.此课题即为研究OATP 1B1基因多态性与新生儿高胆红素血症的相关性.方法 用聚合酶链式反应-限制性片段长度多态性(PCR-RFLP)方法分析220例高胆红素血症新生儿及200名对照者OATP 1B1 T521/A388G基因型,观察基因突变频率及基因型分布、基因多态性与疾病的相关性及对患儿血清总胆红素、结合胆红素、非结合胆红素水平的影响.结果 在高胆红素血症新生儿中,OATP 1B1 T521C等位基因突变频率显著下降,仅为8.2%.野生型的患者比例要显著高于对照组中野生型个体比例,达到84.1%.携带C等位基因的个体患病风险下降(OR=0.530,95%CI=0.328～0.857).血清总胆红素、结合胆红素、非结合胆红素水平在OATP 1B1A388G野生型患者中最高,杂合子次之,突变纯合子最低.结论 OATP 1B1 T521C多态性在新生儿高胆红素血症患儿中存在明显差异,OATP 1B1 A388G多态性显著影响新生儿高胆红素血症患儿血清胆红素水平.OATP 1B1 T521C/A388G是和新生儿高胆红素血症相关的重要基因多态位点.     

High-intensity phototherapy for the treatment of severe nonhaemolytic neonatal hyperbilirubinemia

Aim: To describe the clinical approach to term and near‐term newborn infants with severe hyperbilirubinaemia and to analyse the effect of high‐intensity phototherapy on total serum bilirubin (TSB) levels. Methods: We analysed a cohort of 116 newborn infants with severe nonhaemolytic hyperbilirubinaemia (TSB ≥ 20 mg/dL/342 μmol/L). All patients were treated with high‐intensity phototherapy. The main outcomes were reduction in TSB levels in the first 24 h of phototherapy, incidence of exchange transfusion, pathological brainstem auditory evoked responses and pathological findings on neurological examination at discharge. Results: The mean birth weight and gestational age were 3161 ± 466 g and 37.8 ± 1.6 weeks. Mean initial TSB concentration was 22.4 ± 2.4 mg/dL. Per cent decreases in TSB after 2, 4, 6, 12, 18 and 24 h of phototherapy were 9.4%, 16%, 23%, 40%, 44% and 50%, respectively. No infant was treated with exchange transfusion. Brainstem evoked response audiometry (BAER) was performed in 100% of the patients, and in three of them, this examination was altered. However, when repeated 3 months later, these BAER examinations were normal. Neurological examination was normal in all patients. Conclusions: High‐intensity phototherapy significantly reduces TSB in nonhaemolytic severe hyperbilirubinaemia and decreases the need for exchange transfusion.     

Neurodevelopmental outcome at 1 year in Zimbabwean neonates with extreme hyperbilirubinaemia

The study concentrates on estimating the magnitude of the effect of a single risk factor, maximum total serum bilirubin (TSB) in excess of 400 μmol/l (23.4 mg/dl), on the neurodevelopmental outcome of 50, singleton, Zimbabwean neonates at 1 year of age. At 1 year corrected age the Bayley Scales of Infant Development (BSID) was administered. Two infants died and five were lost to follow up. TSB was neither associated with birth weight nor with gestational age. Of 43 infants with a TSB >400 μmol/l (23.4 mg/dl),11(26%) scored abnormal on the BSID at 1 year of age and 5 (12%) infants developed the choreo-athetoid type of cerebral palsy. Conclusion Infants with bilirubin levels between 400 and 500 μmol/l (23.4 and 29.2 mg/dl) who scored abnormal or suspect on the Bayley Scales of Infant Development were preterm or had haemolytic disease. All term infants without haemolysis and with bilirubin levels between 400 and 500 μmol/l (23.4 mg/dl–29.2 mg/dl) were normal at 1 year of age. Received: 19 February 1998 / Accepted: 22 June 1998     

Overhead is superior to underneath light‐emitting diode phototherapy in the treatment of neonatal jaundice: A comparative study

Aim: To compare the efficacy of overhead and underneath light‐emitting diode (LED) devices in the treatment of neonatal jaundice. Methods: We compared two LED phototherapy devices: the neoBLUE device, which provides overhead illumination, and the neoBLUE cozy device, which provides illumination from underneath the infant. The models we used had similar LED sources and provided similar light intensities (30 µW/cm²/nm). Infants with hyperbilirubinemia were assigned to one of two groups according to the phototherapy device used (group 1, overhead illumination, 181 infants; group 2, underneath illumination, 61 infants). Recorded variables included birthweight, gender, family history, aetiology of jaundice, total duration of phototherapy and total serum bilirubin (TSB) concentration at the initiation of phototherapy, at 12‐hour intervals and just before the cessation of phototherapy. The rates of decrease in TSB concentration were calculated. Results: There were significant differences in the mean duration of phototherapy and in the rate of decrease in TSB concentration between the two groups. The mean duration of phototherapy in group 2 was higher than in group 1 (P= 0.037). The rate of decrease in TSB in group 1 was higher than in group 2 (P= 0.01). Conclusion: These results suggest that when phototherapy is used in the treatment of neonatal jaundice, the direction from which the light is applied should be considered in addition to light source intensity.     

Cardiac Troponin T and Cardiac Dysfunction in Extremely Low-Birth-Weight Infants

Extremely low-birth-weight (ELBW) infants frequently manifest signs of cardiac dysfunction requiring inotropic support. It is not clear if this is due to cardiac injury, which can be monitored by measuring cardiac troponin T (cTnT). We performed a nested prospective cohort study at a university level III neonatal intensive care unit. The study included 27 infants weighing between 500 and 999 g. Exclusion criteria included evidence of sepsis, use of postnatal steroids, and cardiac anomalies. Measurements included serum cTnT and echocardiogram in the first 48 hours of life. The mean serum cTnT level of the study population was 0.52 ± 0.38 ng/ml. It was higher in those with lower Apgar scores (0.89 ± 0.37 if 5-minute Apgar < 4 vs 0.36 ± 0.26 ng/ml, p < 0.001) and correlated to initial base deficit (r = −0.37, p < 0.05). Infants who required inotropic support had higher cTnT levels than those who did not (0.73 ± 0.43 vs 0.39 ± 0.29 ng/ml, p < 0.03). cTnT concentrations did not relate to simultaneous echocardiographic measures of cardiac function. In ELBW infants, serum cTnT levels are higher than normally seen in term infants and adults, and they are higher in infants with greater perinatal stress as well as those who show evidence of cardiac dysfunction requiring pressor support.     

Extreme hyperbilirubinemia in newborn infants

This study was undertaken to determine the frequency and investigate the etiology of extreme hyperbilirubinemia (total serum bilirubin [TSB]>or=25 mg/dL [428 micromol/L]) in newborns admitted to a neonatal intensive care unit in southern Turkey. The charts of 93 term and near-term infants admitted with TSB levels of 25 mg/dL (428 micromol/L) or greater in the first 30 days after birth were retrospectively reviewed. During the 4.5-year study period, 774 infants were admitted to our unit with neonatal jaundice. Ninety-three (12%) of these infants had TSB levels of 25 mg/dL (428 micromol/L) or greater. The mean TSB level in the 93 cases was 30.1+/-5.7 mg/dL (514.7+/-97.5 micromol/L), and the peak levels ranged from 25.0 to 57.4 mg/dL (428-981.5 micromol/L). Thirty-three (35.5%) of the 93 babies had TSB levels of 30 mg/dL (513 micromol/L) or greater. Eighty-nine of 93 infants were being exclusively breast-fed. Nineteen babies were isoimmunized, 7 were bacteremic, 2 of the 39 babies tested for glucose-6-phosphate dehydrogenase had this enzyme deficiency, and 1 of the 71 infants tested for thyroid function had hypothyroidism. No cause for extreme hyperbilirubinemia was found in 61 (65.6%) cases.     

Preterm infants with low immunoglobulin G levels have increased risk of neonatal sepsis but do not benefit from prophylactic immunoglobulin G

OBJECTIVE: In a prospective, randomized, placebo-controlled, multicenter study, we evaluated the prevention of neonatal infections with intravenous immunoglobulin G (IVIgG) prophylaxis for preterm infants (gestational age <33 weeks) with umbilical cord blood IgG levels < or =4 g/L. STUDY DESIGN: Intravenous IgG or placebo (albumin), 1 g/kg body weight, was given on days 0, 3, 7, 14, and 21 to 81 infants with umbilical cord blood IgG levels < or =4 g/L: (1) IVIgG group, n = 40, mean (SD) gestational age 27.5 (2.2) weeks and birth weight 1.06 (0.39) kg; (2) placebo group, n = 41, mean (SD) gestational age 27.7 (2.5) weeks and birth weight 1.13 (0.38) kg. Infants with umbilical cord blood IgG levels >4 g/L (n = 238) served as a separate comparison group. Neonatal infections according to European Society of Pediatric Infectious Disease criteria were monitored until 28 days of life. RESULTS: Infants with IgG levels < or =4 g/L at birth who received IVIgG had no significant reduction in infectious episodes or mortality rate when compared with those given placebo. However, infants with a serum concentration of IgG >4 g/L at birth had significantly fewer infectious episodes (culture-proven sepsis) than infants with low serum concentrations of IgG (< or =4 g/L) when compared at the same gestational ages (26 to 29 weeks, P <.003). CONCLUSIONS: Prophylactic immunotherapy with IVIgG did not improve the immune competence in preterm infants with low serum IgG concentrations at birth. We speculate that a spontaneously high serum IgG concentration at birth reflects placenta function and is an indicator of a more mature immune system capable of protecting the preterm infant against severe neonatal infections.