新生儿脐血Toll样受体变化及其意义

目的观察新生儿脐血单个核细胞（MNC）rrLR4、TLR2mRNA的表达。方法将46例无窒息新生儿及40例窒息新生儿根据胎龄分组,分离脐血MNC,测定其TLR4／2mRNA表达及上清中TNF-α水平。另外将TLR4／2mRNA表达水平与TNF-α水平进行相关分析。结果无窒息新生儿中足月儿TLR4／2mRNA及TNF-O／．水平分别为0．75±0．12、0．63±0．08、2502．6±273．1ng／t,胎龄≥32周但〈37周早产儿分别为0．37±0．04、0．32±0．03、1218．8±145．7ng／t,胎龄〈32周早产儿分别为0．26±0．03、0．20±0．03、811．8±105．2ng／t;窒息新生儿中足月儿TLR4／2mRNA及TNF-α．水平分别为0．58±0．07、0．50±0．06、1946．4±244．2ng／t,胎龄≥32周但〈37周早产儿分别为0．29±0．03、0．26±0．03、970．0±94．3ng／t,胎龄〈32周早产儿分别为0．17±0．02、0．14±0．02、652．6±60．3ng／t;成人TLR4／2mRNA及TNF-α水平分别为2．71±0．75、2．61±0．33、9270．1±1098．3ng／t。早产儿、足月儿TLR4／2mRNA及TNF-α水平均低于成人,胎龄越低,TLR4／2mRNA及TNF-α水平越低。窒息新生儿TLR4／2mRNA及TNF-α的表达水平均低于同胎龄无窒息新生儿（P〈0．01）。TLR4／2mRNA表达水平与TNF-O／．水平呈正相关关系。结论新生儿,特别是早产儿,TLR水平低下,可能是新生儿天然免疫能力低下,容易患败血症等严重感染性疾病的重要原因之一。     

Urinary nitric oxide in newborns with infections

BACKGROUND: Neonatal sepsis is a major problem in newborn nurseries because of the difficulty in early diagnosis and because of the high morbidity and mortality. The objective of the present study was to investigate whether urinary nitric oxide (NO) levels could be useful for the diagnosis of infected newborns. METHODS: Newborns with suspected infection according to previously defined criteria between ages of 1-7 days and 8-30 days were included as the study groups (p) to be compared with age-matched healthy controls (c). Urine NO levels were assayed by Sievers NOA based on chemiluminescence and expressed as corrected for urine creatinine. RESULTS: 20 newborns with suspected infection at 1-7 days of age (group 1p) were compared with 45 healthy age-matched newborns (group 1c). 16 newborns with suspected infection at 8-30 days of age (group 2p) were compared with 15 healthy age-matched newborns (group 2c). The groups were similar with regard to birth weight and gestational age; however, the urinary NO levels in newborns with suspected infection at 1-7 days of age (80.25+/-60.68 micromol/mg creatinine) were higher than in healthy newborns (25.45+/- 19.35 micromol/mg creatinine). Similarly, newborns with suspected infection at 8-30 days of age had higher urinary NO levels (81.78+/- 40.43 micromol/mg creatinine) than age-matched controls (36.99+/-24.58 micromol/mg creatinine; p < 0.05). The sensitivity of urinary NO levels to detect infection was 50% in both age groups, and the specificity was 95% for 1-7 days of age and 93% for 8-30 days of age. Groups 1p and 2p were similar with regard to NO production. Altogether 12 patients had culture-proven sepsis, 11 patients had clinical sepsis, and 13 patients had other infections. The NO levels were similar in patients with culture-proven and clinical sepsis and higher than in patients with other infections. No difference was observed among NO levels of patients with gram-positive and gram-negative sepsis. CONCLUSIONS: Urinary NO levels which are quick and easy to measure are higher in infected newborns as compared with controls, and although the specificity is good, the sensitivity of the test is low, necessitating the use of another marker in addition to NO.     

Low levels of apolipoprotein A1 are not contributors to the low lecithin-cholesterol acyl transferase activity in premature newborn infants

Umbilical cord sera were obtained from three groups of newborn infants; group I (n = 8) and group II (n = 12) weighed less than 1500 g and between 1500 and 2500 g, respectively. Group III (n = 16) was full term and weighed more than 2500 g. Lecithin-cholesterol acyl transferase activities, determined as the rates of esterification of [3H]cholesterol, were 0.13 +/- 0.01, 0.17 +/- 0.01, and 0.26 +/- 0.01 (mean +/- SEM) nmol/h/ml for groups I, II, and III, respectively. The adult value (n = 8) was 0.96 +/- 0.01 nmol/h/ml. The respective apolipoprotein A1 (apo-A1) levels were 52 +/- 6, 59 +/- 4, and 67 +/- 4 (mean +/- SEM) mg/dl. Serum level of apo-A1 in adults was 137 +/- 6 mg/dl. Plasma high-density lipoprotein cholesterol levels increased with gestational age. However, in newborn infants, high-density lipoprotein apo-lipoprotein B, total cholesterol, and triglyceride levels, were significantly lower than in adults. These data indicate that serum levels of lecithin-cholesterol acyl transferase activity significantly (p less than 0.01) increase whereas the levels of apo-A1 do not significantly change with the gestational age. Also, in full-term newborns, lecithin-cholesterol acyl transferase activity is only 27%, whereas apo-A1 levels are 49% of adult values. Therefore, lower levels of apo-A1 do not account for the significantly lower activity of lecithin-cholesterol acyl transferase in preterm as compared to full-term newborn infants.     

Extracellular release of bactericidal/permeability-increasing protein in newborn infants

Upon activation, polymorphonuclear leucocytes (PMN) release bactericidal/permeability-increasing protein, (BPI) from their azurophil granules. BPI selectively binds to the lipopolysaccharide (LPS) on gram-negative bacteria and induces their death. This study examined plasma BPI concentration levels in healthy newborns and in newborns with clinical sepsis, and the ability of PMN from preterm and term infants to release BPI. We also studied the release of myeloperoxidase (MPO), and the surface expression of adhesion molecule CD11b on PMN. In infants with clinical sepsis, plasma BPI concentration was higher, 27.8 microg/L [8.6-883; median (range)] (n = 11), than in healthy term infants 8.9 microg/L (3.9-179) (n = 17), and in adults 7.3 microg/L (0.7 -18.4) (n = 15); p = 0.014, Kruskal-Wallis. In preterm infants (n = 8), the ability of PMN to release BPI in vitro after stimulation with PMA was 8.8, in term infants it was 15.9 (n = 29; p > 0.05 vs. preterm infants) and in adults 23.4 ng/10(6) PMN (n = 15; p = 0.024 and p > 0.05 vs. preterm and term infants, respectively). The corresponding values of MPO were 20.0 ng/10(6) (11.3-46.7) in preterms, 19.0 ng/10(6) (2.2-223.7) in terms, and 27.8 ng/10(6) (9.1-80.7) in adults; p = 0.67 between groups. In infants with clinical sepsis, CD11b level was higher, 292 RFU (234-403) than the basal CD11b expression levels in healthy newborn infants, 116 RFU (76-145); P = 0.0001. FMLP-stimulated PMN CD11b expressions in preterm cord blood, 1071 RFU (552-1286) and in term cord blood, 918 (567-1472) were on the same level, but lower than that in adult blood, 1592 (973-1946); p < 0.001, ANOVA. Our findings suggest that in preterm infants the ability to release BPI is lower than in adults and term infants. These findings suggest that premature neonates have an impaired ability to mobilize BPI, possibly contributing to their marked susceptibility to infections with Gram-negative bacteria.     

Plasma vasoactive intestinal polypeptide in the newborn infant

Vasoactive intestinal polypeptide (VIP) has been suggested as a possible contributor to the development of gastrointestinal problems. VIP is produced by nerve endings in the intestinal tract and appears to have marked effects on gut motility and its blood flow. Since necrotizing enterocolitis and feeding intolerance are common problems in the newborn, we examined the plasma VIP responses to feeding in healthy preterm and term newborn infants. Plasma VIP levels were measured in 20 full-term newborn infants (gestation of 39.4 +/- 0.9 weeks, mean +/- SD, and weight of 3,351 +/- 477 g) and 38 preterm infants (gestation of 27-35 weeks, weight of 920-2,440 g). In term infants, cord blood samples were obtained from the umbilical artery and vein and then before and after the feed. For preterm infants, blood samples were obtained prior to the introduction of oral feeds during the first week, and then before and after feeding once a week over the next 4 weeks. Feeding ranged from diluted premature formula to special care (24 calories per ounce) for the preterm, and breast milk or regular commercial formula for the term infants. Twenty-one healthy adults, age 25-42 years, were studied for comparison. In the term newborn infants, the plasma VIP levels in the umbilical venous blood were lower, although not statistically significant (p = 0.06), than the umbilical arterial blood (10.78 +/- 5.89 vs. 13.54 +/- 6.71 pmol/L), suggesting placental metabolism of VIP. After birth, there was a significant increase in plasma VIP levels (18.89 +/- 10.07 pmol/L, p = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)     

Serum adiponectin concentrations in newborn infants in early postnatal life

Serum adiponectin levels were investigated in 28 small-for-gestational-age (SGA) and 34 appropriate-for-gestational-age (AGA) term neonates to examine how fetal growth correlates with adiponectin levels. A blood sample for determination of adiponectin was obtained during the first 24 h of life. The levels of serum adiponectin were significantly higher in all newborn infants than in healthy children (28.7 +/- 17.0 versus 9.3 +/- 6.1 microg/mL; p < 0.01). There was a significant difference in adiponectin levels between SGA and AGA infants (23.2 +/- 14.8 versus 33.2 +/- 17.5 microg/mL; p=0.02). For all of the newborn groups, serum adiponectin levels correlated positively with birth weight (r=0.27, p <0.05) and head circumference (r=0.30, p <0.05). There was no relationship between serum adiponectin levels and gestational age, birth length, blood glucose levels, or blood sampling time after birth. There was no gender difference in adiponectin levels in the entire newborn group (30.0 +/- 19.7 versus 28.0 +/- 15.5 microg/mL, in male and female infants). Our results suggest that hyperadiponectinemia and a positive relationship between the serum levels of adiponectin and birth weight in newborns cannot be explained by the low percentage of body fat alone. Lower adiponectin levels in SGA infants than in AGA infants are unlikely to suggest insulin resistance in intrauterine growth-retarded infants in early postnatal life but may be a predisposing factor in the future development of insulin resistance or type 2 diabetes.     

Plasma methionine enkephalin levels in the human newborn at birth

Plasma met-enkephalin immunoreactivity (MET-ENKi) and catecholamine levels were measured in umbilibal cord blood from 46 healthy newborn infants. Clinical data including Apgar scores, birth weight, gestational age, route of delivery, fetal heart tracings and arterial blood gas values were also obtained. Thirty-nine infants were delivered by the vaginal route. All but 1 infant delivered by cesarian section had undergone a trial of labor. Plasma MET-ENKi in the newborn infants was markedly greater than levels found in healthy adult volunteers: 360 +/- 25 versus 25 +/- 2 pg/ml, respectively. MET-ENKi levels were similar in umbilical arterial and umbilical venous blood, and in infants delivered vaginally or by cesarian section.     

Ontogeny of unconjugated estriol in fetal blood and the relation of estriol levels at birth to the development of respiratory distress syndrome

Unconjugated estriol (E3) was quantified in serum of umbilical cord blood of 533 newborn infants, 360 of whom were delivered between 23 and 37 wk of gestation. Serum E3 levels rose (F = 7.71, p less than 0.0001) as a function of gestational age; the mean concentration of E3 at 37.5-42 wk of gestation (105 ng/ml, n = 173) was significantly higher than that in serum of newborns delivered at 23-28 wk of gestation (63 ng/ml, n = 33). Umbilical cord serum levels of E3 were significantly higher among newborns delivered vaginally between 31.5 and 42 wk of gestation than among newborns delivered by cesarean section (p less than 0.005). Although serum E3 levels correlated highly (p less than 0.0001) to newborn weight throughout the entire period of gestation, there was no relationship of newborn weight to umbilical serum E3 levels within a given gestational period. Also, the umbilical serum levels of E3 in male infants were similar to those of female infants at each gestational age. Significant changes in umbilical serum levels of E3 as a function of gestational age were not observed among newborns (n = 90) who developed respiratory distress syndrome (RDS). The mean umbilical serum concentration of E3 in newborns delivered at 34.5-37 wk of gestation who developed RDS were significantly lower (p less than 0.01) than that in similar aged newborns whose lung function was normal.(ABSTRACT TRUNCATED AT 250 WORDS)     

Postnatal IgG levels in very-low-birth-weight infants. Preliminary observations

We studied the gammaglobulin levels (IgG) postnatally, serially, in 42 infants of very low birthweight (mean +/- SD 971 +/- 225 g) with gestational ages ranging from 23 to 31 weeks. Eighteen infants (42.8%) had IgG levels of less than 100 mg/dl by a mean postnatal age of 71.2 +/- 16 days. The lowest level was 22 mg/dl in an infant whose birthweight was 700 g. Sixteen of the 42 infants (mean birthweight 946.8 +/- 260 g) also had cord blood IgG levels determined. The mean cord blood IgG was 413.5 +/- 163 mg/dl. This had dropped to 140.3 +/- 87 mg/dl by 57 days, a drop of 66 percent. As expected, the lowest IgG levels postnatally was a reflection of the degree of prematurity and the length of postnatal age. Such extremely low levels of IgG have not been reported previously.     

Changes in leptin concentration during the early postnatal period: adjustment to extrauterine life?

There are substantial alterations in fuel homeostasis immediately after birth. Leptin is a putative regulator of energy metabolism. Consequently, the aim of this study was to examine whether there are changes in circulating leptin concentrations during the early postnatal period. Umbilical cord mixed blood samples were taken at delivery, and a venous blood sample was obtained at 3 d of age from 38 healthy newborn infants (20 male, 18 female; gestational age 36.3 to 41.9 wk) for analysis of leptin concentration with radioimmunoassay. Cord plasma leptin concentration was 9.7+/-5.2 microg/L (mean+/-SD), with no gender difference between male (8.6+/-4.6 microg/L) and female (10.9+/-5.6 microg/L) infants. In male newborns, cord plasma leptin concentration correlated with arm circumference (r = 0.48, p < 0.05), and in female newborns with body mass index (r = 0.62, p < 0.01), thickness of the s.c. fat (r = 0.54, p < 0.05), and arm circumference (r = 0.72, p < 0.01). By the third postnatal day, plasma leptin decreased similarly in male (to 1.8+/-0.4 microg/L, p < 0.001) and female (to 2.3+/-0.8 microg/L, p < 0.001) infants, when there was a significant gender difference in leptin levels (p = 0.01). At 3 d of age, plasma leptin correlated with weight (r = 0.49, p < 0.05) and arm circumference (r = 0.49, p < 0.05) in female but not in male newborns. In conclusion, 1) circulating leptin already correlates with adiposity at birth in female but not in male newborn infants and 2) leptin decreases markedly in both genders by the third postnatal day, and the gender difference with higher leptin levels in females develops by that time. Thus, the postnatal decrease in plasma leptin concentration may be a physiologically feasible adaptation to profound alterations in fuel homeostasis during the first days of extrauterine life.     

晚期新生儿中性粒细胞减少症的危险因素分析

目的 分析晚期新生儿中性粒细胞减少症(NLN)的危险因素及诊治过程.方法 回顾性收集新生儿重症监护室2019年7月至2020年1月收治的早产儿及危重新生儿的临床资料.新生儿出生第2～4周连续2次血中性粒细胞绝对值(ANC)<1.5×109/L者纳入NLN组(n=46).按照1?:?2比例匹配血ANC一直≥1.5×109...     

Serum amyloid A (SAA) protein and high-sensitivity C-reactive protein (hsCRP) in healthy newborn infants and healthy young through elderly adults

AIM: To determine the levels of serum amyloid A (SAA) protein and high-sensitivity C-reactive protein (hsCRP) in different age groups. METHODS: Serum samples from 70 healthy newborn infants, 80 blood donors and 81 healthy elderly individuals were analysed using a nephelometric method. The 231 samples were grouped as follows: 35 umbilical cords, 35 newborns, 48 young adults, 28 middle-aged adults, and 85 elderly adults. RESULTS: Serum levels of both SAA and hsCRP were lower in umbilical cords than in the newborns and young, middle-aged and elderly adults (p<0.0001). The SAA and hsCRP levels were comparable in newborns, and young and middle-age adults, but higher in elderly adults (p<0.0001-0.03). SAA (r2=0.159, p<0.0001) and hsCRP (r2=0.059, p<0.0001) were positively correlated with age and to each other (r2=0.385, p<0.0001). CONCLUSION: Serum levels of SAA and hsCRP in umbilical cord blood are close to the detection limit and lower than in the other age groups investigated. The elderly have generally higher levels than the younger age groups, which require higher decision levels in inflammatory diseases, including infections. In newborns and young and middle-aged adults, the lower decision levels of 10 mg/l for SAA and 5 mg/l for CRP are suggested.     

Plasma protein Z levels in healthy and high-risk newborn infants

AIM: To evaluate plasma protein Z (PZ) levels in healthy and high-risk newborn infants. METHODS: A longitudinal observational study was conducted. Inclusion criteria were: healthy term and preterm newborns normal for gestational age and newborns belonging to one of the following groups: newborns small for gestational age (SGA), newborns affected by respiratory distress syndrome (RDS), newborns from mothers with pre-eclampsia. Newborns with sepsis, congenital malformation or haemorrhagic disorders were excluded. Plasma PZ levels, protein C (PC) concentration, PC activity and protein-induced vitamin K absence levels were measured. RESULTS: 53 newborns were enrolled into the study. PZ and PC antigen levels varied significantly among analysed subgroups on day 1 (p < 0.01): lower levels of these inhibitors were found in RDS newborns (group C), newborns from mothers affected by pre-eclampsia (group D) and SGA newborns (group E) than in healthy term and preterm newborns (groups A and B). CONCLUSION: PZ deficiency occurs in newborns affected by severe RDS, in newborns from pre-eclamptic mothers and in SGA newborns, probably owing to activated coagulation in the first two conditions and to reduced PZ synthesis in the last condition.     

新生儿脐血血脂水平的检测

目的　了解正常足月新生儿脐血血脂水平 ,确定筛查家族性高胆固醇血症患儿的血脂上界。方法　采用全自动生化分析仪 ,分别采用酶法和一步法检测 2 42例正常足月新生儿脐血的总胆固醇 (TC)、甘油三酯 (TG)、低密度脂蛋白胆固醇 (LDL C)、高密度脂蛋白胆固醇 (HDL C)的含量。结果正常足月新生儿脐血TC、TG、LDL C和HDL C分别为 ( 1 69± 0 40 )mmol/L、( 0 2 3± 0 12 )mmol/L、( 0 81± 0 2 1)mmol/L和 ( 0 5 8± 0 16)mmol/L ,除女婴的HDL C值高于男婴外 (P <0 0 5 ) ,其余指标男女差异无显著性 (P >0 0 5 )。结论　筛查家族性高胆固醇血症患儿的脐血血脂上界值推荐为TC≥2 47mmol/L和LDL C≥ 0 89mmol/L。     

Pharmacokinetics of cefoperazone in newborn infants

We studied the disposition of two 100 mg/kg doses of cefoperazone given intravenously 12 hr apart in ten newborn infants. Peak levels were a mean 352 +/- SD 75 and 371 +/- 68 micrograms/ml immediately after the first and second dose, respectively, with corresponding troughs of 60 +/- 10 and 76 +/- 28 mcg/ml 12 hr later. Mean half-life was 6.5 +/- 0.9 hr and decreased with increasing gestational age and birthweight. Steady-state volume of distribution averaged 410 +/- 40 ml/kg and total clearance 0.78 +/- 0.13 ml/min X kg and neither varied with gestational age nor birthweight. No untoward physical or laboratory effects were noted. Additional studies including postnatal age effects on kinetics, efficacy, and cerebrospinal fluid penetrance are necessary prior to widespread use of this potentially valuable antibiotic in newborn infants.     

Evaluation of interleukin-6, tumour necrosis factor-α and interleukin-1β for early diagnosis of neonatal sepsis

The objective of this study was to assess the contribution of interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) to an early diagnosis of early-onset neonatal sepsis. A cohort of 117 newborn infants delivered during a 1-y period had IL-6, TNF-alpha and IL-1beta, blood and cerebrospinal fluid (CSF) cultures, leucocyte and platelet count collected on the initial evaluation of possible early-onset sepsis. They were divided into four groups: I, positive blood and/or CSF cultures; II, probably infected with clinical sepsis but negative cultures; III, same as group II but mother received antibiotic antepartum; and IV, newborn infants that did not receive any antibiotic therapy. There were no differences among the four groups with respect to mean gestational ages and birthweights, median Apgar scores, type of delivery, or number of newborn infants with leucocyte count <5000 mm(-3) or >25000 mm(-3), platelet count <100000 mm(-3), immature/total neutrophil ratio >0.2, absolute neutrophil count <1000mm(-3) and median IL-1beta levels. Median IL-6 and TNF-alpha levels were significantly higher in groups with patients with a diagnosis of clinical sepsis than in controls. The optimal cut-off point was 32 pg ml(-1) for IL-6 and 12 pg ml(-1) for TNF-alpha. The combination of both provided a sensitivity of 98.5%. In conclusion, the combination of IL-6 and TNF-alpha is a highly sensitive marker of sepsis in the immediate postnatal period.     

Dosage regimen of arbekacin for methicillin-resistant Staphylococcus aureus infection in newborns and infants

BACKGROUND: Arbekacin (ABK) is an aminoglycoside antibiotic that has a dose-dependent bactericidal action. Because it inhibits the production of toxic shock syndrome toxin-1 (TSST-1) by methicillin-resistant Staphylococcus aureus (MRSA), it has attracted attention as a therapeutic drug for MRSA infection. In this study, the authors investigated the pharmacokinetics of ABK based on therapeutic drug monitoring (TDM), in order to establish an effective dosage regimen with minimal adverse reactions in MRSA infected newborns and infants. METHODS: Arbekacin was administered to nine MRSA infected newborns and infants between October 2000 and March 2002. Following the initial ABK administration, blood was collected and the blood concentration of ABK was measured. The blood concentrations of ABK were analyzed by the two-compartment model or by a model-independent method in order to elucidate the pharmacokinetics of ABK. Pharmacokinetic analysis was performed using WinNonlin Professional V3.1. RESULTS: The mean age at initial ABK administration was 24.0 +/- 26.0 days (postconceptional age: 39.2 +/- 3.9 weeks). The increase in the peak blood concentration of ABK was 2.40 +/- 0.20 microg/mL per mg ABK per kg bodyweight, showing great consistency among cases. The elimination half-life of ABK was 0.22-3.52 h in the alpha phase (T(1/2alpha)) and 2.42-33.44 h in the beta phase (T(1/2beta)), showing great variation among cases. The distribution volume was 0.75 +/- 0.13 L/kg, and systemic clearance was 0.054 +/- 0.012 L/h/kg. ABK alleviated clinical symptoms and inflammations in all cases. CONCLUSION: Nine newborns and infants with MRSA infection and various underlying diseases were successfully treated with TDM-based administration of ABK with no severe adverse reactions.     

Cord blood levels of cytokines as predictors of early neonatal sepsis

AIM: To investigate whether cord blood levels of C-reactive protein, interleukin-1beta, interleukin-6, interleukin-8, tumour necrosis factor-alpha and the soluble receptor of interleukin-2, are useful markers in the diagnosis of early neonatal sepsis. DESIGN: Umbilical cord blood samples were obtained at birth from 261 neonates, but 5 of these newborns were excluded from the study. Group I included 10 newborns that developed early neonatal sepsis with a positive blood culture; Group II included 11 newborns with non-infectious perinatal diseases; Group III, which served as the control group, included 10 randomly selected patients, matched for gestational age, among the 235 healthy newborn babies. RESULTS: There were no differences among the three study groups in levels of C-reactive protein. interleukin-1beta, tumour necrosis factor-alpha and the soluble receptor of interleukin-2. Interleukin-6 was significantly elevated in Group I (360.4+/-157.8 pg/ml) and Group II (158.8+/-122.3 pg/ml), when compared with Group III (8.6+/-3.12 pg/ml) (p < 0.01), whereas interleukin-8 was significantly elevated in Group I (389.3+/-115.9 pg/ml) compared with Groups II (30.2+/-5.1 pg/ml) (p < 0.05) and III (33.9+/-8.6 pg/ml) (p < 0.05). A cut-off of 100.8 pg/ml for interleukin-6 obtained by the ROC (receiver operating characteristic) method gave a sensitivity of 50% and a specificity of 87%, and a cut-off of 111.7 pg/ml for interleukin-8 showed a sensitivity of 78% and a specificity of 91%. CONCLUSION: While cord blood levels of interleukin-6 appear to be related to pathological conditions in the perinatal period (infectious and non-infectious), interleukin-8 seems to be a good predictor of early bacterial neonatal infection.     

Serum leptin levels in twins and singleton newborns

BACKGROUND AND OBJECTIVE: Leptin is produced by the human placenta besides adipose tissue and is suggested to be related to fetal growth. In order to find out whether multiple pregnancy is a factor affecting serum leptin levels, we compared neonatal serum leptin concentrations of twins and singleton newborns who were all appropriate for gestational age (AGA). INFANTS AND METHODS: Thirty newborns were studied. Group 1 consisted of 15 infants from twin pregnancies and group 2 (control group) consisted of 15 infants from singleton pregnancies. Serum samples were taken at 24 hours following delivery and leptin concentrations were measured. RESULTS: There were no significant differences in birth weight, gestational age and male/female ratio between infants of twin and single gestations. However, serum leptin concentrations of twins (mean +/- SEM: 1.13 +/- 0.35 ng/ml) were significantly lower than of the singleton infants (4.27 +/- 0.63 ng/ml) (p < 0.001). CONCLUSION: Twin pregnancy might be a factor affecting serum leptin concentrations in newborn infants.     

Pharmacokinetics and dosing of arbekacin in preterm and term newborn infants

BACKGROUND: The objective of the present study was to determine pharmacokinetic variables and to characterize a new initial dosing regimen of arbekacin (ABK) for preterm and term newborn infants. PATIENTS AND METHODS: Subjects were 40 infants treated with ABK in a tertiary care neonatal unit over a period of 18 months. At birth, the infants were 23 5/7-40 0/7 weeks and weighed 530-3428 g. Serum ABK concentration was measured at two points in a course of treatment. Data were analyzed by a one-compartment model to obtain volume of distribution (Vd) and clearance (CL) of ABK. These variables were correlated with the patients' demographic and laboratory data. The new initial dosing regimen was determined based on these data. RESULTS: Sixty pairs of blood samples were taken from the infants. They were divided into three groups: preterm early (PE), gestational age (GA) < 37 weeks and postnatal age (PNA) < 28 days; preterm late (PL), GA < 37 weeks and PNA >or= 28 days; and term (T), GA >or= 37 weeks and PNA < 28 days. The Vd was 0.50 +/- 0.02, 0.48 +/- 0.04, and 0.43 +/- 0.03 L/kg, and CL was 0.59 +/- 0.04, 1.12 +/- 0.10, and 0.78 +/- 0.09 mL/min per kg (mean +/- SEM) in PE, PL, and T, respectively. The new dosing regimen is 5 mg/kg every 48 h, 5 mg/kg every 24 h, and 4 mg/kg every 24 h for PE, PL, and T, respectively. CONCLUSIONS: With the new dosing regimen, more infants achieved serum ABK levels within the optimal range than the conventional one.