Search

This study aimed to determine whether the protease/protease inhibitor balance and neutrophil activity is of pathophysiological importance in the severity and resolution of respiratory distress syndrome (RDS) and the eventual development of neonatal chronic lung disease (CLD). Ventilated preterm infants with RDS (n = 43) were studied during their first week of life. Tracheobronchial aspirate fluid (TAF) concentrations of neutrophil lipocalin, the elastase- and neutrophil protease-4 (NP4) complex concentrations, and α[sub 1]-antitrypsin (α[sub 1]AT), antichymotrypsin (ACT) and secretory leucocyte protease inhibitor (SLPI) levels were analysed. Free proteolytic and elastolytic activities were also determined. CLD correlated with low α[sub 1]AT (p = 0.02) and ACT (p = 0.02) levels at 3–4 d of age and low SLPI (p = 0.03) at 7–8 d of age. No correlations were found between CLD or severity of RDS (as judged from radiological examination) and neutrophil lipocalin, elastaseand NP4–α[sub 1]AT complexes during the first week of life, with one exception: RDS X-ray severity and the elastase-α[sub 1]AT complex concentration were correlated at 3–4 d of age (p = 0.02). Free proteolytic activity occurred in the TAF of 7/30 infants tested on day 3–4 and free elastolytic activity in 1 patient. During the rest of the first week of life no free elastolytic or proteolytic activities were observed. Caesarean section was correlated with low levels of SLPI on day 3–4 (p = 0.01), NP4 (p = 0.03) and ACT (p = 0.05) on day 5–6. Gestational age was positively correlated with protease inhibitors and their complexes at 3–4 d of age. Conclusion: Free proteolytic or elastolytic activity in the TAF of RDS infants in the first week of life occurred by way of exception. Elastase–/NP4–α[sub 1]AT complex or neutrophil lipocalin levels were not correlated with the development of CLD. The correlation between CLD and low α[sub 1]AT or ACT at 3–4 d and SLPI at 7–8 d of age may be due to either immaturity or complex formation. The severity of RDS as judged from radiological examination was correlated with elastase–α[sub 1]AT complex on day 3–4. The main hypothesis, that TAF protease/protease inhibitor levels or imbalance and leucocyte activity are important factors indicating a high risk of severe RDS and subsequent CLD development, was principally not confirmed. [ABSTRACT FROM AUTHOR]

Maternal chlamydial antibodies were determined in cord sera of 41 infants who developed neonatal chlamydial conjunctivitis and compared with the antibody profile of infants who had been exposed to Chlamydia trachomatis at birth by their isolation positive mothers but in whom conjunctivitis did not develop. No protective effect could be attributed to maternal antibodies transferred to the infants. Paired sera samples were collected from 18 infants with chlamydial conjunctivitis. Chlamydial IgM antibodies were detected in four of these 18 cases at the time diagnosis was established by isolation. An additional eight cases had developed chlamydial IgM at the time the convalescent sera samples were taken, on average on day 40. At that time symptoms had disappeared after systemic treatment had been given. Thus chlamydial IgM antibodies were eventually shown in two thirds of infants with chlamydial conjunctivitis who were all systemically treated and clinically healed. These data suggest a cautious assessment of chlamydial IgM in the diagnosis of chlamydial pneumonia. [ABSTRACT FROM AUTHOR]

Pronounced growth restriction (GR) occurs after very preterm birth. The interaction between IGF-I, nutritional intake, and growth was evaluated prospectively in 64 infants with a mean (SD) GA of 25.7 (1.9) wk. Blood sampling of IGF-I and measurements of weight, length, and head circumference were performed weekly until discharge. Daily calculation of nutritional intake was performed. Standard deviation scores (SDSs) for growth parameters defined two growth phases: GR phase (birth until lowest SDS) and catch-up (CU) phase (lowest SDS until 35 gestational weeks). IGF-I concentrations during the first postnatal weeks were low and increased at 30 wk GA, irrespective of GA at birth, coinciding with initiation of CU growth. Concentrations of IGF-I were positively associated with change in weight SDS during the GR phase, p = 0.001 and CU phase, p = 0.004-0.027. Protein and energy intake were not associated with change in SDS weight during the GR phase as opposed to the CU phase (p < 0.001, respectively). Nutritional intake did not correlate to concentrations of IGF-I before 30 wk GA. IGF-I is associated with growth at an earlier postnatal age than nutrient intake and the effect of nutrition on levels of IGF-I may be restricted to the period of established CU growth.

Most extremely low birthweight (ELBW; <1,000 g) infants will survive if cared for at a tertiary neonatal intensive care unit, and should be given optimal nutrition for brain development. Human milk confers nutritional and non-nutritional advantages over infant formula, and is started during the first hours of life. In Sweden, most ELBW infants are fed individually with mother's own milk (preferred) and banked milk, with supplementary parenteral nutrition. There is an enormous variation particularly in the fat and protein content of milk between mothers, during the day and the course of lactation. Infrared macronutrient analyses on 24-hour collections of mother's milk are performed once a week allowing for optimal protein and energy intakes. All banked milk is analyzed, and the most protein-rich milk is given to a newborn ELBW infant. After 2 weeks, the milk may be fortified if the protein or energy intakes need to be further increased, and fortification is continued throughout the tube-feeding period. Parenteral nutrition is continued until the enteral intake constitutes 75-80% of the total volume intake. Protein markers, e.g. serum urea and transthyretin, are assessed, and growth is monitored by measurements of weight, crown-heel length and head circumference., (Copyright (c) 2009 S. Karger AG, Basel.)

Overview: Use of a suction-induced epidermal mini-erosion for serial sampling of dermal interstitial fluid (IF) in 16 newborn infants with gestational age ranging from 24 to 42 weeks is reported., Results: The mini-erosion formed reproducibly and electron microscopy showed that the split was located within the epidermis. IF was sampled serially by suctioning during 1-3 days without signs of stress or pain. IF sample volumes (10-50 microl) did not decrease with time. Glucose values in IF and blood were correlated (r(s) = 0.542; p = 0.000). IF glucose was lower than blood glucose on all 3 days. The epidermis regenerated within 4 +/- 0.9 days (mean, SD) after sampling was terminated. There were no complications., Conclusion: Serial transdermal sampling was performed without stress or pain in newborn infants. Systemic and temporal differences between glucose measured in IF and blood were observed., (Copyright (c) 2005 S. Karger AG, Basel.)

Respiratory distress syndrome (RDS) and chronic lung disease of prematurity (CLD) are associated with inflammation of the airways and interstitial tissue of the lung. It is hypothesized that RDS severity and the risk of developing CLD may be correlated with neutrophil gelatinase-associated lipocalin (NGAL), a marker of leucocyte activity, human elastase-alpha1-antitrypsin complex (HEAT) or free and complexed neutrophil protease 4 (NP4), markers of proteolytic enzyme secretion from granulocytes. Thirty-three preterm infants with RDS were enrolled in the study and plasma sampled between 3 and 14 days of life. NGAL, HEAT and NP4 concentrations varied widely in infants with RDS. Significant correlations between subsequent development of CLD and plasma concentrations of HEAT and NP4, respectively, were found on days 3-4 of life, p=0.006 and p=0.02, respectively.

Premature infants receive high dietary zinc and often glucocorticoids as a treatment for chronic lung disease. A piglet model was developed to investigate intestinal zinc transport and distribution of tissue zinc in response to treatment with short-term (5 d) glucocorticoid therapy or a high zinc diet. Piglets (13-15 d old; n = 21) were randomly allocated to: 1) dexamethasone (DEX) therapy (1.5 mg/kg intramuscularly twice a day), 2) high zinc diet (15.3 mmol/kg), or 3) control group (0.3 mmol dietary zinc/kg and saline intramuscularly twice a day). Pig weight, formula intake, urine volume, and blood glucose were monitored. At necropsy, tissue samples were obtained to measure zinc in plasma and zinc and metallothionein in liver and small intestinal mucosa. Velocity of zinc uptake by intestinal brush border membrane vesicles was measured using 65Zn tracer. Maximum uptake rate and Km for zinc uptake by brush border membrane vesicles were significantly greater (p < 0.05) in DEX compared with control and high zinc groups. DEX-treated piglets had a significantly lower (p < 0.05) zinc efflux rate across brush border membrane vesicles compared with that of the control. The high zinc group had a higher liver (p < 0.05) and mucosal (p < 0.05) zinc content and higher liver metallothionein concentration (p < 0.001) compared with the control and DEX groups. Weight gain over 5 d was not different among groups. Daily blood glucose was higher (p < 0.05) in DEX versus control and high zinc groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Concentrations of 11 plasma proteins were measured in 28 healthy, growing, very low birth weight, appropriate-for-gestational-age infants fed varying levels of human milk protein intake (range 1.7 to 3.9 g/kg per day). Significant positive correlations were found between mean protein intake and concentrations of 7 of the plasma proteins studied (transthyretin, retinol-binding protein, and transferrin: P less than .001; vitamin D-binding protein and apolipoprotein B: P less than .01; albumin and apolipoprotein A I: P less than .05). A weak negative correlation with mean protein intake was seen for the plasma level of orosomucoid, whereas no significant correlations were found for the plasma concentrations of fibronectin and alpha 1-antichymotrypsin. Protein intake, not energy intake, constituted the main contribution to the changes in the concentrations of transthyretin, retinol-binding protein, and transferrin. The levels of plasma transthyretin and transferrin were also strongly correlated with weight and length growth of the infants during the study as well as with other indicators of protein nutritional status such as preprandial concentrations of plasma amino acids and serum and urine urea. These data indicate that of the 11 plasma proteins studied, transthyretin, transferrin, and retinol-binding protein are the most suitable to evaluate protein nutritional status in very low birth weight infants.

Preprandial plasma and urine amino acid concentrations were measured in 28 growing, very low birth weight, appropriate-for-gestational-age infants randomly assigned to either protein-unenriched (n = 14) or human milk protein-enriched (n = 14) human milk. The two groups of infants had similar birth weights (900 to 1500 g) and gestational ages (26 to 32 weeks). The study was initiated at a mean age of 19 days when the infants tolerated full feeding volumes and lasted for a mean time of 28 days. Mean protein intake values were 2.1 +/- 0.3 and 3.6 +/- 0.3 g/kg per day (mean +/- SD) and weight gain values were 26.6 +/- 7.4 and 35.1 +/- 3.6 g/day in the protein-unenriched and the protein-enriched groups of infants, respectively. Human milk protein enrichment resulted in significantly increased concentrations of all plasma amino acids except serine, taurine, and histidine. Most urine amino acid concentrations correlated with protein intake and with the plasma concentrations, suggesting that the effects of protein quality and quantity can be evaluated by measuring urinary amino acid concentrations alone, thereby making such studies less invasive. Infants fed protein-unenriched human milk had growth rates below the estimated intrauterine rate as well as low plasma and urine amino acid concentrations, indicating suboptimal protein intake levels. When the plasma concentrations of the essential amino acids in the protein-enriched infants from the present study were compared with concentrations found in the literature in fetal and umbilical cord plasma, both were found to be much higher.(ABSTRACT TRUNCATED AT 250 WORDS)

Plasma samples obtained at birth from 70 very low birth weight (VLBW) infants (gestational age 24 to 34 weeks) and from 20 term infants were analysed for concentrations of 12 different proteins. The plasma concentrations of albumin, transthyretin (TTR), retinol-binding protein (RBP), vitamin D-binding protein, apolipoprotein A I, fibronectin, orosomucoid and alpha 1-antichymotrypsin were significantly lower in the VLBW infants than in the term infants, whereas the values of alpha-fetoprotein (AFP) were significantly higher in the VLBW infants. No differences were found between the two groups for apolipoprotein A II, apolipoprotein B and transferrin. Birth asphyxia and sex had no influence on the measured plasma protein concentrations. The plasma concentrations of apolipoprotein A I and A II were significantly lower in small-for-gestational age (SGA), VLBW infants compared with appropriate-for-gestational age (AGA), VLBW infants. Possible acute inflammation (defined as raised concentrations of orosomucoid or alpha 1-antichymotrypsin) was associated with significantly higher values of vitamin D-binding protein in both VLBW and term infants, suggesting that this protein may act as an acute phase protein in newborn infants.

Urea concentrations in serum and urine were measured in 28 growing, very low birth weight, appropriate-for-gestational age infants fed varying human milk protein intakes (range 1.7 to 3.9 g/kg/day). We found a high correlation between serum urea values at the end of the study and mean protein intake (rs = 0.85, p less than 0.001) and between urinary urea concentrations in eight-hour urine collections and protein intake (rs = 0.81, p less than 0.001). All serum and urine urea values were below 1.6 and 18 mmol/l, respectively, at protein intakes less than 3 g/kg/day. Higher protein intakes caused higher serum and urinary urea concentrations. We also found a strong correlation between the individual serum and urinary urea values at the end of the study (rs = 0.90, p less than 0.001). The presented data are consistent with the growth data previously reported and indicate that inadequate or excessive protein intakes can be detected by measurement of urea concentrations in serum and/or urine. If urine urea samples alone can be used for estimating optimal protein intake, painful blood sampling procedures could be obviated.

222 consecutive fetuses found by ultrasound to be in breech presentation in the 33rd gestational week were followed with repeated examinations in weeks 35 and 38. Ninety-one of these fetuses persisted in breech presentation until delivery, while cephalic version occurred in 131. The frequency of hip joint instability was 21% in the breech delivered group and 1.5% in the vertex delivered group. The position of the fetal legs was established at each ultrasound examination. The intrauterine fetal attitude was classified as extended when the fetuses had extended knees and maximally flexed hips at all ultrasound examinations. This occurred in 30 breech delivered fetuses, 47% of which developed hip joint instability. Only 8% of the breech born infants with flexed legs in utero developed hip joint instability. It is concluded that instability of the hip joint is a consequence of the intrauterine attitude, rather than of the breech delivery per se.

Of 858 pregnant women studied in matched rectal, urethral and urine cultured specimens, 186 (22%) were found to be colonized by group B streptococci (GBS). GBS were detected significantly more often in rectal specimens (159) than in urethral specimens (108) or in urine specimens (64). This is supporting evidence for the gastrointestinal tract as the main habitat of GBS. Of 1786 women whose urine was sampled at delivery, GBS were isolated from 128 (7%), in 22 of whom (1% of the total) GBS were present in quantities greater than or equal to 10(4) colony forming units (cfu)/ml urine. Neonates born to women with greater than or equal to 10(4) cfu GBS/ml urine were apparently at greater risk for neonatal infection, as they were more commonly and more heavily colonized than were the newborns of women with lower quantities of GBS in urine, or if positive urethral or rectal specimens were considered. The incidence of preterm delivery or obstetric infection was not higher among women in whom GBS were isolated in specimens from any of the 3 sites; foetal distress was more common among their children, but not neonatal respiratory or infectious diseases of which the incidence was low and difficult to assess statistically.

To analyse the incidence of fetal growth retardation and its impact on perinatal mortality and neonatal morbidity, pregnancies complicated by intra-uterine growth retardation (IUGR) were compared with matched non-IUGR pregnancies. The IUGR group included all infants born in the city of Malmö during the study period and having a birthweight of 2 standard deviations or more below the mean birthweight for gestational age. The gestational age of all pregnancies was assessed with ultrasound in the first half of pregnancy. The IUGR fetuses were more vulnerable during delivery, and emergency cesarean section due to imminent fetal asphyxia was performed more frequently, but Apgar scores were similar in both groups. The frequency of respiratory disorders was lower in the IUGR group than in the non-IUGR group when corticosteroid-treated pregnancies were excluded. The IUGR group required slightly longer care on the neonatal ward than the non-IUGR group, but not more intervention. The IUGR group as a whole had an unexpectedly low neonatal complication rate, such complications as did occur being related to preterm birth rather than to growth retardation.

The outcome of breech delivery was evaluated by a neonatal neurological score and a follow-up examination at 18 months of age. The subjects were 132 children identified by ultrasound to be in breech presentation in the 33rd gestational week. 62 were born in breech presentation, while 70 turned to vertex presentation. During the early neonatal period, a neurological score was obtained based on the results of 29 items concerning posture, muscle tone, reflexes and reactions. Although there was no difference, in neurological score or in general development when the entire breech and vertex groups were compared, the SGA (small-for-gestational age) infants and the infants with low Apgar scores of the breech group had the poorest neurological scores. The contribution of certain maternal and fetal factors to postnatal condition was evaluated by a multiple linear regression analysis. Within the breech group, relationships were found between the neurological score and the variables intrauterine growth, fetal sex, and low Apgar score. A major part (66%) of the variation in neurological score was explained by the combination of these variables. These factors should therefore be taken into consideration when deciding on the mode of delivery in breech presentation.

225 fetuses with ultrasonically determined gestational age were shown by ultrasound to be in breech presentation in the 33rd gestational week. The biparietal diameter (BPD) and the mean of two perpendicular abdominal diameters (AD) were measured ultrasonically in gestational weeks 33, 35, and 38. Based on these measurements, fetal weight was estimated and compared with weight, length, and head circumference at birth and at 18 months of age. 42% of the fetuses were born in breech presentation (breech group) and 58% in vertex presentation (vertex group). The mean birth weight corrected for gestational age was 4.9% lower in the breech group than in the vertex group, which corresponds to the lower intra-uterine values of BPD and AD found in the breech group. The weight differences at birth still persisted at 18 months of age. There were no differences between the groups regarding head circumference or length, either at birth or at 18 months of age.