贫困农村和富裕城市6月龄婴儿粪钙卫蛋白水平的差异及其影响因素

目的 比较贫困农村与富裕城市6月龄婴儿粪钙卫蛋白（FC）水平的差异及喂养对婴儿FC水平的影响。方法 2009年10月至2010年6月收集云南贫困农村以及上海城区6月龄婴儿的粪便样品,采用ELISA法检测FC水平;同时获得婴儿母乳喂养和辅助食品添加的信息。比较两地婴儿FC水平差异,母乳喂养与辅助食品添加对婴儿FC水平的影响。非正态分布数据以中位数（全距）表示。结果 共调查145名婴儿,剔除10名部分资料缺失的婴儿。135名婴儿进入分析,其中96名来自贫困农村,39名来自富裕城市。富裕城市婴儿在生后前6个月的体重增长显著高于贫困农村婴儿,（5.0±0.9） kg vs （4.3±0.9） kg ,P<0.01。135名婴儿中有36名婴儿的FC水平>600 μg·g-1,其中贫困农村婴儿34/96名（35.4%）,富裕城市婴儿2/39名（5.1%）,差异有统计学意义（P<0.01）。FC水平≤600 μg·g-1的99名婴儿中,FC水平的中位数为172.0（24.5～595.9）μg·g-1,明显高于成人正常水平上限（50 μg·g-1）。不同性别婴儿的FC水平差异无统计学意义（P=0.828）。富裕城市37名FC水平≤600 μg·g-1婴儿的FC水平中位数为138.8 μg·g-1（26.2~557.2 μg·g-1）;贫困农村62名FC水平≤600 μg·g-1婴儿的FC水平中位数为196.4 μg·g-1（24.5~595.9 μg·g-1）,差异有统计学意义（P<0.05）。母乳喂养以及不同辅助食品添加对婴儿的FC水平无显著影响。结论 6月龄婴儿的FC水平显著高于成人。贫困农村6月龄婴儿的FC水平明显高于富裕城市婴儿,该现象是否预示着贫困农村婴儿中存在肠道隐性感染,是否因此而影响婴儿生长发育,值得进一步的研究。     

早产儿生后2周内粪便钙卫蛋白水平检测的临床研究

目的 动态测定早产儿生后2周内粪便钙卫蛋白（fecal calprotectin,FC）水平,分析影响FC分泌的临床因素,探讨其在评价早产儿胃肠功能的价值.方法 2012年5-9月中国医科大学附属盛京医院新生儿科收治的胎龄≤32周或出生体重≤l 200g的早产儿47例,根据生后第7d的喂养情况分成喂养耐受组29例及喂养不耐受组18例.收集生后第1次胎便、第7d及第14 d最后一次粪便（以下依次简称为FC1、FC2和FC3）50-100 mg.用酶联免疫吸附法（ELASA）测定FC水平.结果 47例早产儿FC3水平明显高于FC1和FC2水平（P＜0.05）;FC1与FC2水平差异无统计学意义（P＞0.05）.母亲分娩前有产前感染的早产儿FC1水平明显高于无产前感染者（P＜0.05）.FC2水平与生后抗生素使用时间（d）呈显著负相关（r =-0.325,P＜0.05）.喂养不耐受组FC2水平明显低于喂养耐受组（P＜0.05）.喂养耐受组FC2、喂养不耐受组FC3水平分别与第7d和第14 d的肠道喂养量呈显著正相关（r =0.433,0.479,P＜0.05）.结论 产前感染及生后肠道喂养可促进早产儿胃肠道分泌FC,生后早期FC水平可反映早产儿早期胃肠道喂养情况,可作为评价早产儿生后早期消化道功能的无创性生物学指标.     

Illumina高通量测序技术分析早产儿出生后肠道菌群变化的初步研究

目的 初步探讨NICU早产儿出生后肠道菌群变化特征及其与败血症的关系。方法 以复旦大学附属儿科医院NICU住院的早产儿为研究对象,于出生后第1天采集胎粪,之后于每周龄时或评估败血症时采集粪便样本,直至出院或生后8周。采用Illumina高通量测序技术对粪便样本中所有细菌的16S rRNA-V3区进行DNA测序,应用MG-RAST V3.3.6分析和统计样品序列数目、操作分类单元（OTU）数量,分析肠道菌群物种丰度和分布,并进行聚类分析。结果 3例早产儿共采集生后1、7、14和21 d的12份粪便样本,其中5份样本PCR扩增失败,7份样本(例1生后14、21 d;例2生后7、21 d;例3生后7、14、21 d)DNA测序成功进入分析。3例早产儿平均胎龄为（31.3±0.8）周,平均出生体重为（1 540±144） g。3例均生后应用抗生素,其中例1母亲有产前抗生素暴露史;例2在住院过程中发生全身炎症反应综合征。①7份样本稀疏曲线表明测序深度充分。物种多样性分析显示OTU值为381~608,微生物丰度较高,且与日龄呈正相关,其中例2生后7 d样本肠道菌群多样性最低;②7份样本共检测到18个菌门,均以放线菌门、拟杆菌门、厚壁菌门和变形菌门为优势菌门;变形菌门在例1生后14和21 d样本分别占97.52％和49.11％,放线菌门在例2生后7 d样本占99.46％;③共检测到172个科,其中63科为7份样本共有;相对丰度≥1％的科共检测到10个,例2生后7 d样本棒状杆菌科占97.90％,21 d样本中葡萄球菌科占27.16％;④聚类分析显示,同一研究对象不同时点肠道微生物相似性较高。结论 早产儿产前抗生素暴露及出生后早期抗生素暴露可能会显著降低肠道微生物的多样性,影响正常菌群的定植。发展为败血症的早产儿生后肠道微生物多样性较低,以致病菌占优势的肠道微生物区可能与败血症的发生相关。     

早产儿血浆血管活性肠肽水平与喂养不耐受的临床研究

目的：观察早产儿生后血浆内血管活性肠肽（VIP）水平的变化趋势,探讨其与早产儿喂养不耐受（FI）的相关性。方法：112例早产儿为研究对象,其中53例为FI组,59例为对照组,应用放射免疫法检测生后1、4、7、14 d的血浆VIP浓度。结果：（1）早产儿FI组生后1、4、7 d空腹血浆中VIP浓度分别为129±46、144±32及166±31 pg/mL,明显低于对照组的195±63、197±31及205±34 pg/mL（P＜0.05）,但随胎龄、日龄、肠内喂养奶量的增加而逐渐升高。生后14 d FI 组的VIP浓度为198±41 pg/mL,对照组为202±48 pg/mL,两组比较差异无统计学意义;（2）早产儿胎龄越小,FI的持续时间越长;（3） FI组早产儿生后1 d VIP水平与FI的持续时间之间存在负相关（r=-0.799,P＜0.05）。结论：血浆VIP水平变化可能与早产儿FI的发生、发展密切相关,早期监测血浆VIP水平有助于及早判断发生FI的可能性。     

非营养性吸吮对早产儿营养胰岛素及生长抑素水平的影响

目的：非营养性吸吮(NNS)对早产儿的有益作用尚存在不同意见，该文探讨了NNS对早产儿营养、血浆胰岛素(INS)及生长抑素(SS)水平的影响。方法：将38例需经鼻胃管喂养的健康早产适于胎龄儿，随机分成NNS和无非营养性吸吮组(N-NNS)两组，用同一种配方乳喂养，并用放射免疫法测定INS、SS水平。结果：NNS组恢复出生体重时间 8.8 ±3.7 d 较N-NNS组11.1±3.0 d缩短，差异有显著性(P<0.05)，1周、2周时体重、身长、头围的变化无差异(均P>0.05)；NNS组肠道营养热能达每日418.4 kJ/kg 的时间为 12.3±5.1 d 较N-NNS组15.7±5.2 d 缩短，差异有显著性(P<0.05)；鼻胃管留置时间NNS组为13±10 d，N-NNS组为17±12 d，差异无显著性(P>0.05)。NNS组胃残留的发生率(16.7%)较N-NNS组(50%)减少(P<0.05)。早产儿喂奶后1，2周INS水平NNS组为 37.1±11.3 μU/ml、50.3±18.4 μU/ml高于N-NNS组29.6±8.8 μU/ml、40±9.9 μU/ml，而SS水平NNS组 454.6±136.4 pg/ml，595.6±172.1 pg/ml 低于N-NNS组 595.3±260.1 pg/ml，727.2±220.8 pg/ml，差异均有显著性意义(均P<0.05)。结论：NNS可促进INS的分泌，抑制SS的分泌，NNS有利于早产儿生后胃肠道的继续发育，加速体格生长，提高经肠道喂养的耐受性。     

新生儿缺氧缺血性脑病血清神经元特异性烯醇酶和肿瘤坏死因子水平的变化

目的：观察新生儿缺氧缺血性脑病(HIE)时血清神经元特异性烯醇酶(NSE)和肿瘤坏死因子(TNF)水平的变化。方法：分别用酶联免疫法和放射免疫法检测15例足月正常新生儿(对照组)及25例足月HIE新生儿(HIE组)在生后24h内、3d和7～10d血清NSE和TNF水平。结果：HIE组在生后24h内、3d和7～ 10d的血清NSE浓度分别为(13.93± 2.71) μg/L ,(12.46±2.36 )μg/L和(8.41± 1.44 )μg/L ,对照组NSE浓度分别为(8.04±1.53)μg/L,(7.92±1.73) μg/L和 (7.56±1.02 )μg/L ;HIE组血清TNF浓度分别为(0 .401±0.183)μg/L ,(0.339±0.126)μg/L和(0.183±0.076) μg/L ,对照组TNF浓度分别为(0 .170± 0.085) μg/L ,(0 .179± 0 .116 ) μg/L和 (0 .16 5± 0 .0 5 2 ) μg/L。HIE组在生后 3d内血清NSE水平和TNF水平均显著高于正常对照组 (P <0 .0 1) ,7～ 10d与正常对照组无显著差异 (P>0.05 )。结论：NSE和TNF参与了新生儿HIE的病理生理过程。     

早产儿视网膜病血清血管内皮生长因子色素上皮衍生因子的检测和临床意义

目的 观察早产儿生后血清血管内皮生长因子（VEGF）和色素上皮衍生因子（PEDF）水平的动态变化，为早期诊断及预测早产儿视网膜病(ROP)提供依据。方法 从2006年6月至2007年1月复旦大学附属儿科医院新生儿病房的早产儿中按入选标准和排除标准确认研究对象。将出生体重≤2 000 g或胎龄≤34周的患儿进行ROP筛查，将发生ROP患儿作为ROP组；选取与ROP组胎龄和出生体重相匹配的早产儿作为ROP对照组。将未发生ROP的早产儿根据胎龄分为<32周，~33+6周和~36+6周3个胎龄组。所有入选早产儿生后第7、14、21、28和35天分别进行采血，分离血清，经ELISA法检测血清VEGF和PEDF的水平。采用SPSS 13.0中混合线性模型 重复数据测量、相关性分析、t检验和单变量方差分析法进行数据分析。结果 入选的早产儿共170例，其中6例在生后14 d内自动出院失访而排除，11例发生ROP。未发生ROP的153例早产儿中，<32周54例，~33+6周48例，~36+6周51例。各胎龄组血清VEGF水平随日龄的增长而下降（r=－0.167，P=0.000），与第7天比较，差异有统计学意义（第14天，P=0.010；第21天，P=0.000），而自21 d起基本保持稳定；血清PEDF水平在生后14 d内变化无统计学意义（P=0.713），14 d后随日龄的增长而升高（r=0.287，P=0.000），与第7天比较，差异有统计学意义（第21天，P=0.008；第28天，P=0.001；第35天，P=0.000）。胎龄对VEGF和PEDF水平的影响较出生体重显著，胎龄越小，生后血清VEGF和PEDF水平越高，在出生体重的协同作用下，胎龄与VEGF和PEDF水平均呈负相关（r=－0.162，P=0.027；r=－0.165，P=0.024）。早产儿生后PEDF/VEGF比值恒定，且随日龄的增长而升高（r=0.237，P=0.000）。ROP组血清VEGF（P=0.000）水平在生后21 d均较ROP对照组低，且随日龄的增长反有上升； PEDF水平随着日龄的增长未能体现上升趋势；PEDF/VEGF比值在生后第7天显著升高（P=0.036），生后35 d内随着日龄的增长反有下降（r=－0.449，P=0.047）。结论 发生ROP的早产儿血清VEGF、PEDF水平以及PEDF/VEGF比值在生后1～3周可有变化趋势的改变，提示若早产儿生后血清VEGF水平较同胎龄者低，且随着日龄的增长反有升高，PEDF水平随着日龄的增长未能升高，PEDF/VEGF比值在第7天显著升高，在生后28 d内随着日龄的增长反有下降，可能预示着ROP的发生。这可能有助于临床医生更早地预测ROP的发生，从而积极采取有效的干预措施预防和减轻ROP的发生。     

血小板活化因子及其乙酰水解酶在新生儿感染中的变化及临床意义

目的 检测感染新生儿血浆血小板活化因子（PAF）水平及其乙酰水解酶（PAF-AH）的活性,探讨两者在新生儿感染中的变化及临床意义。方法 以复旦大学附属儿科医院新生儿科病房收治的日龄<30 d的新生儿为研究对象。依据感染部位和程度分为全身感染组、局部感染组及非感染组;依据日龄分为早期新生儿（≤7 d）和晚期新生儿（>7 d）。采集研究对象桡动脉血标本,对全身感染组中合并器官功能衰竭的患儿在感染的第1、3、5和7天增加采集桡动脉血标本。测定血浆PAF水平（μg·L-1）和PAF-AH活性（μmol·L-1·min-1）。分析感染程度、性别、日龄和出生体重对血浆PAF水平和PAF-AH活性的影响,比较不同感染组PAF水平和PAF-AH活性的差异,观察全身感染合并器官功能衰竭患儿血浆PAF水平和PAF-AH活性在病程1～7 d的变化趋势。结果 研究期间共收治247例新生儿,男146例,女101例;平均日龄9.2（1~57 ）d;平均胎龄35.85（27~43）周;平均出生体重2 517（906~4 750 ）g。全身感染组91例,局部感染组63例,非感染组93例。①新生儿血浆PAF水平与感染程度相关（P=0.000）;血浆PAF-AH活性与感染程度及日龄（P均为0.000）相关。②全身感染组血浆PAF水平(9.5±8.1)显著高于局部感染组(5.3±3.2)及非感染组(4.6±3.5)。早期新生儿中,全身感染组血浆PAF-AH活性(5.7±2.7)显著低于局部感染组(7.3±2.9) 和非感染组(7.3±2.5)。晚期新生儿中,全身感染组血浆PAF-AH活性(7.0±2.5)显著低于局部感染组(9.7±2.2) 和非感染组(9.7±2.7)。③全身感染组合并器官功能衰竭的9/12例存活患儿在病程的1~7 d血浆PAF水平呈下降趋势,PAF-AH活性呈上升趋势。3/12例死亡患儿中两者的变化趋势则相反。④全身感染组31/91例确诊败血症患儿中,革兰阴性菌感染者血浆PAF水平（13.1±11.0）显著高于革兰阳性菌感染者（5.4±3.9 ）,PAF-AH活性（4.9±2.1）显著低于革兰阳性菌感染者（7.9±2.4 ）。结论 新生儿严重感染时血浆PAF水平增高,PAF-AH活性降低,两者的变化趋势与预后相关。     

早产儿出生早期粪便钙卫蛋白水平变化及临床意义

目的：探讨早产儿生后早期粪便钙卫蛋白（fecal calprotectin,FC）水平及影响因素,寻找早产儿胃肠道损伤的早期诊断指标。方法：将38例胎龄为29～33周的早产儿按早产原因分为胎膜早破（premature rapture of membrane,PROM）组、自发性早产(spontaneous preterm birth,SPB)组及有医学指征早产(indicated preterm birth,IPB)组,收集出生后第1次胎便及生后第3天最后1次粪便（以下简称为第1次和第2次粪便）,用ELISA法测定FC水平。结果：38例早产儿第1次与第2次FC水平差异无统学计意义（P>0.05）。PROM组第1次FC水平明显高于IPB组（P0.05）。结论：胎膜早破及出生窒息促进早产儿胃肠道分泌FC,生后早期FC水平可反映早产儿早期胃肠道喂养状况,可作为评价早产儿生后早期消化道功能的指标。     

早产儿血清表皮生长因子测定的临床意义

目的：表皮生长因子与胎儿器官发育和功能成熟密切相关,该研究探讨早产儿窒息及早产儿坏死性小肠结肠炎患儿血清中表皮生长因子含量及其临床意义。方法：采用放射免疫方法检测10例足月新生儿和35例早产儿生后血清表皮生长因子浓度。结果：35～37周和28～34周早产儿血清表皮生长因子含量0.617±0.22μg/L,0.540±0.31μg/L明显低于足月新生儿0.723±0.18μg/L,差异有显著性(P<0.01);窒息早产儿与足月儿相比血清表皮生长因子水平降低更为明显0.446±0.24μg/Lvs0.723±0.18μg/L;坏死性小肠结肠炎早产儿与足月儿比较血清表皮生长因子浓度没有明显降低0.771±0.44μg/Lvs0.723±0.18μg/L,差异无显著性。结论：血清表皮生长因子水平与胎龄有关;窒息可使表皮生长因子水平降低。     

不同胎龄及出生体重早产儿血游离肉碱变化特点

目的检测不同胎龄及出生体重早产儿血游离肉碱（FC）浓度,为制定早产儿FC补充治疗方案提供依据。方法选取3 368例早产儿为研究对象。根据胎龄（GA）分为超早产（EPTB,GA<28周）组（n=39）、极早产（VPTB,28≤GA < 32周）组（n=405）、中期早产（MPTB,32≤GA<34周）组（n=507）、晚期早产（LPTB,34≤GA<37周）组（n=2 417）;根据出生体重（BW）分为超低出生体重（ELBW,BW < 1 000 g）组（n=36）、极低出生体重（VLBW,1 000 g≤BW < 1 500 g）组（n=387）、低出生体重组（LBW,1 500 g≤BW < 2 500 g）组（n=1 873）、正常出生体重（NBW,2 500 g≤BW≤4 000 g）组（n=1 072）。于生后72 h~7 d内采血进行FC浓度测定并进行比较。结果 EPTB、VPTB组FC浓度明显高于MPTB、LPTB组（P < 0.05）,MPTB组FC浓度明显高于LPTB组（P < 0.05）;胎龄越小,FC的95%医学参考范围下限越高。ELBW、VLBW组FC浓度明显高于LBW、NBW组（P < 0.05）,LBW组FC浓度明显高于NBW组（P < 0.05）;出生体重越低,FC的95%医学参考范围下限越高。结论极/超早产儿、极/超低出生体重儿血FC浓度明显升高,并且随着胎龄及出生体重的增加呈明显下降的趋势。     

Influence of gestational age and intrauterine growth on leptin concentrations in venous cord blood of human newborns

BACKGROUND: The ob gene product leptin is involved in the regulation of body weight and energy expenditure, suggesting a potential role of leptin in embryonal and fetal development and progression of pregnancy. In term infants, leptin concentrations showed a positive correlation with birth weight. We aimed at comparing leptin cord blood levels in AGA (appropriate for gestational age) to SGA (small for gestational age) preterm and term newborns. PATIENTS AND METHODS: Ninety-seven human newborns, 47 females and 50 males, 33 born at term and 64 born before 36 weeks of gestation, were studied prospectively. Leptin concentrations in venous cord blood were determined using a specific RIA (radioimmunoassay). RESULTS: In term newborns, mean gestational age (GA) was 39 weeks (wk) (+/- 0.7 wk) and mean birth weight (BW) was 3316 g (+/- 473 g); in preterm newborns (n = 64), mean GA was 30 wk (+/- 5.0 wk) and mean BW was 1398 g (+/- 505 g). Mean standard deviation score of birth weight (BW SDS) was calculated as - 0.47. Mean leptin concentrations in term newborns differed significantly from those in preterm newborns (9.21 +/- 2.63 ng/ml vs. 1.58 +/- 0.88 ng/ml; p < 0.0001). In preterm and term infants, leptin concentrations showed a linear correlation with BW (r = 0.46; p < 0.0001) and GA (r = 0.48; p < 0.0001), respectively. Leptin levels were best predicted by an exponential regression model with GA (Leptin = exp(- 4.41 + 0.14 x GA); r = 0.61; p < 0.0001). Using multivariate regression analysis (r = 0.57; p < 0.0001), we found significant influences of GA (p < 0.00001) and BW SDS (p < 0.05) on leptin levels. No difference was observed between leptin values in AGA versus SGA preterm infants. CONCLUSION: These data suggest fetal leptin levels to be primarily determined by GA and additionally modulated by growth restriction in term newborns. We found a dramatic increase at weeks 33 to 35 of gestation and no modulation by BW SDS in very preterm infants.     

Coagulation and fibrinolytic systems in the ill preterm newborn

Aim: The activation pattern of the clotting and fibrinolytic systems in 63 preterm infants (GA 31, 6 ± 2.3 weeks) was studied. Methods: The infants were divided into four groups: (i) IRDS, (ii) asphyxia at birth, (iii) sepsis, and (iv) mild infection. A control group was composed of preterm infants without any apparent disease (GA 32 ± 1.8 weeks). Results: During IRDS we found a systemic activation of both coagulation and fibrinolysis at birth which was represented by lower levels of ATIII (27.7 ± 8.8%) and significantly greater levels of TAT (37.9 ± 31.9 ng/ml), D-dimers (1242.7 ± 206.9 ng/ml), tPA Ag (10.9 ± 5.3 ng/ml) and PAI Ag (59.9 ± 16.7 ng/ml) than in the control group. In the asphyxiated newborns there were no significant differences from the controls. During their seventh day of life, a significant reduction of all the analysed parameters (TAT, D-dimers, tPA, PAI) and a significant increase in ATIII were seen in the newborns with IRDS, while no significant modification was observed in the newborns with asphyxia at birth. When the newborns with sepsis were compared with those with mild infection, their TAT and PAI values proved to be significantly higher for the first tests (21.7 ± 18.8 vs 9.2 ± 6.9 μgA and 53.6 ± 14.4 vs 37.7 ± 10.2 ng/ml respectively). During the second tests, 7 days later, only TAT (16.7 ± 14.7 vs 6.3 ± 4 jtg/1) levels remained high while D-dimers (1094.2 ± 400.6 vs 646 ± 200 ng/ml) and tPA (11.3 ± 8 vs 4.9 ± 2 ng/ml) were significantly higher in the septic group of newborns than those with mild infection. Conclusions: These data indicate that there is an activation of the clotting and fibrinolytic systems both in the initial phase of IRDS as well as during sepsis.     

极低出生体质量儿胎粪钙卫蛋白水平及影响因素分析

目的 了解极低出生体质量儿胎粪钙卫蛋白(FC)水平及其影响因素.方法 收集2018年6月—2019年5月住院的极低出生体质量儿出生后第1次胎粪,采用免疫荧光法定量检测胎粪钙卫蛋白水平,并收集患儿一般资料及母孕期资料.结果 共纳入87例极低出生体质量儿,男45例、女42例,中位胎龄30.3周(29.1～31.1周),中位...     

早产儿早期血脂代谢特点及与新生儿呼吸窘迫综合征关系探讨

目的：了解早产儿早期血脂代谢特点及其与新生儿呼吸窘迫综合征（RDS）的关系。方法：将100例适于胎龄早产儿按胎龄或出生体重分组,并以40例足月适于胎龄儿作为对照组,于出生后12 h内静脉采血,测定血浆总胆固醇（TC）、甘油三脂（TG）,低密度脂蛋白胆固醇（LDL-C）及高密度脂蛋白胆固醇（HDL-C）水平;另外,分别根据胎龄及出生体重进一步比较发生RDS与未发生RDS早产儿的血脂水平。结果：随胎龄及体重增加,TG水平呈递增趋势,28~30周组及31~33周组早产儿血浆TG水平均明显低于34~36周早产儿及足月儿（P<0.01）;出生体重≤1499 g组及1500~2499 g组早产儿血浆TG水平均明显低于出生体重≥2500 g早产儿及足月儿（P<0.05）,且出生体重≤1499 g组与1500~2499 g组早产儿之间TG水平差异亦有统计学意义（P<0.01）;而各组新生儿HDL-C、LDL-C及TC水平差异无统计学意义。RDS与非RDS早产儿血浆TC、LDL-C及HDL-C水平差异亦无统计学意义;但在胎龄28~30周组,RDS早产儿的TG水平比非RDS早产儿明显降低（P<0.05）;体重≤1499 g RDS早产儿TG水平低于非RDS早产儿（P<0.05）。结论：早产儿血脂水平与胎龄及体重相关,低TG水平可能是胎龄28~30周及体重≤1499 g早产儿出现RDS的原因之一。     

Anti-oxidant enzymes and related elements in term and preterm newborns

Background:  Although oxidative stress-related diseases mostly affect neonates with extremely low birthweight, healthy preterm newborns might also be at risk of oxidative damages. The aim of the present study was to verify this possibility.
Methods:  Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG), erythrocyte glutathione peroxidase (GSHPx) and superoxide dismutase (SOD), plasma and erythrocyte concentrations of selenium, zinc and copper were measured until 100 days of life in 30 preterm infants with mean ± SD birthweight and gestational age of 1605 ± 122 g and 34.5 ± 0.5 weeks. The control group included 30 term infants with birthweight 3123 158 g and gestational age 39.6 0.7 weeks.
Results:  Throughout the study period urinary 8-OHdG, taken as a marker of oxidative stress, was significantly higher in the preterm than in the term group. Up until 20 days of life, GSHPx activity was significantly lower in the preterm than in the term infants but this was not associated with any apparent selenium deficiency. Conversely, up until 100 days, preterm infants had significantly reduced SOD levels that appeared to reflect a shortage of the elements needed for this enzyme's activity, notably copper, the plasma concentrations of which were constantly and significantly below the control values.
Conclusion:  The nutritional status of the elements related to the anti-oxidant enzymes, especially zinc and copper, should be carefully assessed in preterm infants, even if their birthweight is not extremely low.     

Lack of correlation between fecal elastase-1 levels and fecal nitrogen excretion in preterm infants

We measured fecal elastase-1 (FE1) levels in 34 preterm newborns (15 small-for-gestational-age and 19 appropriate-for-gestational-age) during the first 2 months of life and evaluated whether they were correlated with nitrogen loss in stools. FE1 increased over time, and values were similar in both groups of newborns. Fecal nitrogen was significantly higher in small-for-gestational-age infants. There was no correlation between FE1 levels and fecal nitrogen excretion. Pancreatic proteolytic function was efficient at an early stage in enterally fed preterm newborns. Despite the similar FE1 values, fecal nitrogen loss was significantly higher in small-for-gestational-age preterm infants than in appropriate-for-gestational-age preterm infants.     

Serum pro-hepcidin levels in term and preterm newborns with sepsis

Background:  An iron regulatory peptide hormone, hepcidin, is also part of the innate immune system and is strongly induced during infections and inflammation. The aim of the present study was to determine serum levels of the 60 aa pro-hormone form of hepcidin (pro-hepcidin) in full-term and preterm newborns with sepsis and to determine the possible relationships between pro-hepcidin levels and serum iron and complete blood count parameters.
Methods:  Fifteen preterm newborns with sepsis, 17 healthy preterm, six full-term newborns with sepsis and 16 healthy full-term newborns were included the study. Blood samples were collected from patients with sepsis at the time of clinical diagnosis. Each blood sample was analyzed for complete blood count, serum iron and ferritin concentrations, iron-binding capacity, and pro-hepcidin level.
Results:  The mean serum pro-hepcidin level (mean ± SD) in preterm neonates with sepsis and in healthy preterm newborns was 565.4 ± 519.5 ng/mL and 279.8 ± 227.6 ng/mL, respectively ( P <  0.05). The mean serum pro-hepcidin level in full-term newborns with sepsis and in healthy full-term neonates was 981.4 ± 415.4 ng/mL and 482 ± 371.9 ng/mL, respectively ( P <  0.05). Although the mean serum ferritin levels in the two groups with sepsis were higher when compared with the healthy groups, the difference was not statistically significant in full-term newborns. No statistically significant correlations were found between serum pro-hepcidin levels and any other parameters in each group.
Conclusions:  Serum pro-hepcidin levels were higher in newborns with sepsis (either premature or full-term) than they were in healthy newborns at the time of clinical diagnosis.