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Objectives: Early exposure to mother's own milk (MOM) promotes intestinal barrier maturation in preterm infants. We hypothesized (1) donor human milk (DHM) supplementation reduces intestinal permeability (IP) similar to exclusive MOM and (2) early HM exposure and low IP at 7-10 days postnatal age (PNA) are associated with improved growth outcomes., Methods: IP was measured by the standard sugar absorption test (SAT) in infants <33 weeks gestation between 7-10 days PNA. Nutritional and anthropometric data were recorded. Postnatal growth failure (PNGF) was defined as a decrease in weight z-score >1 from birth to discharge to home., Results: Of 158 preterm infants, the mean (SD) gestational age was 29.9(2.3) weeks and birthweight 1388(424) g. Diet prior to SAT was exclusive MOM [N = 55(35%)], DHM ± MOM [N = 52(33%)], or preterm formula±MOM [N = 51(32%)]. The mean Lactulose(La)/Rhamnose(Rh) ratio was lower in the exclusive MOM [0.06(0.07)] and DBM ± MOM [0.05(0.07)] groups compared to the preterm formula±MOM group [0.11(0.11)], p < 0.01). Cumulative intake >150 ml/kg MOM ± DHM, but not preterm formula within 7-10 days PNA was associated with early intestinal barrier maturation. Low IP was not associated with lower risk of PNGF at discharge., Conclusions: Low IP is associated with cumulative intake of MOM alone or supplemented with DHM > 150 ml/kg within 7-10 days PNA., Clinical Trial Registration: Clinicaltrials.gov NCT01756040 ; web link to study on registry: https://clinicaltrials.gov/study/NCT01756040 ., Impact: Key message Early intestinal barrier maturation is associated with cumulative intake of exclusive MOM alone or supplemented with DHM > 150 ml/kg within 7-10 days after birth, but is not associated with lower risk of PNGF at time of discharge. What it adds to existing literature? This observational study is the first study to demonstrate that supplemental DHM promotes intestinal barrier maturation similar to MOM alone. What is the impact? The findings underscore the importance of early introduction of human milk feeds as MOM or MOM supplemented with DHM in sufficient volume to promote early intestinal barrier maturation., (© 2024. The Author(s), under exclusive licence to the International Pediatric Research Foundation, Inc.)

Previous work has shown that Secretory-IgA (SIgA) binding to the intestinal microbiota is variable and may regulate host inflammatory bowel responses. Nevertheless, the impact of the SIgA functional binding to the microbiota remains largely unknown in preterm infants whose immature epithelial barriers make them particularly susceptible to inflammation. Here, we investigated SIgA binding to intestinal microbiota isolated from stools of preterm infants <33 weeks gestation with various levels of intestinal permeability. We found that SIgA binding to intestinal microbiota attenuates inflammatory reactions in preterm infants. We also observed a significant correlation between SIgA affinity to the microbiota and the infant's intestinal barrier maturation. Still, SIgA affinity was not associated with developing host defenses, such as the production of mucus and inflammatory calprotectin protein, but it depended on the microbiota shifts as the intestinal barrier matures. In conclusion, we reported an association between the SIgA functional binding to the microbiota and the maturity of the preterm infant's intestinal barrier, indicating that the pattern of SIgA coating is altered as the intestinal barrier matures., (© The Author(s) 2023. Published by Oxford University Press on behalf of the British Society for Immunology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: To develop predictive models of Ureaplasma spp lower airway tract infection in preterm infants., Methods: A dataset was assembled from five cohorts of infants born <33 weeks gestational age (GA) enrolled over 17 years (1999-2016) with culture and/or PCR-confirmed tracheal aspirate Ureaplasma status in the first week of life (n=415). Seventeen demographic, obstetric and neonatal factors were analysed including admission white blood cell (WBC) counts. Best subset regression was used to develop three risk scores for lower airway Ureaplasma infection: (1) including admission laboratory values, (2) excluding admission laboratory values and (3) using only data known prenatally., Results: GA and rupture of membranes >72 hours were significant predictors in all 3 models. When all variables including admission laboratory values were included in the regression, WBC count was also predictive in the resulting model. When laboratory values were excluded, delivery route was found to be an additional predictive factor. The area under the curve for the receiver operating characteristic indicated high predictive ability of each model to identify infants with lower airway Ureaplasma infection (range 0.73-0.77)., Conclusion: We developed predictive models based on clinical and limited laboratory information available in the perinatal period that can distinguish between low risk (<10%) and high risk (>40%) of lower airway Ureaplasma infection. These may be useful in the design of phase III trials of therapeutic interventions to prevent Ureaplasma -mediated lung disease in preterm infants and in clinical management of at-risk infants., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: The aim of this study was to develop reference renal saturation (rSrO 2 ) curves in premature infants, depict how they differ from cerebral saturation (rScO 2 ) curves, and evaluate the effect of blood pressure on these values using near-infrared spectroscopy (NIRS)., Methods: This is a prospective cohort study of 57 inborn infants <12 h and <30 weeks gestation. rScO 2 , rSrO 2 , fractional tissue oxygen extraction (FTOE), and mean arterial blood pressure (MAP) were continuously monitored every 30 s for 96 h. Quantile regression was used to establish nomograms, and mean saturation values were evaluated for different MAP ranges., Results: Median rSrO 2 at the start of monitoring was ~10% higher than rScO 2 . rSrO 2 showed a significant decline over time while rScO 2 peaked at 26 h. FTOE demonstrated a similar but inverse trend to their saturation counterparts. rScO 2 declined as MAP increased, while rSrO2 showed a peak and decline as MAP increased., Conclusions: We provide rSrO 2 reference curves for the first 4 days of life, which differ in their trajectory from rScO 2 and from what has previously been reported for rSrO 2 in the full-term population. In addition, we observed a peak and decline in renal saturation with increasing MAP, suggesting a renovascular response to blood pressure changes., Impact: This article depicts reference renal saturation curves during the perinatal transition in preterm infants. We show how renal saturation compares to cerebral saturation trends over time. We describe a peak and decline in renal saturation with increasing MAP, suggesting a renovascular response to blood pressure changes., (© 2022. The Author(s), under exclusive licence to the International Pediatric Research Foundation, Inc.)

"Leaky gut," or high intestinal barrier permeability, is common in preterm newborns. The role of the microbiota in this process remains largely uncharacterized. We employed both short- and long-read sequencing of the 16S rRNA gene and metagenomes to characterize the intestinal microbiome of a longitudinal cohort of 113 preterm infants born between 24 0/7 and 32 6/7  weeks of gestation. Enabled by enhanced taxonomic resolution, we found that a significantly increased abundance of Bifidobacterium breve and a diet rich in mother's breastmilk were associated with intestinal barrier maturation during the first week of life. We combined these factors using genome-resolved metagenomics and identified a highly specialized genetic capability of the Bifidobacterium strains to assimilate human milk oligosaccharides and host-derived glycoproteins. Our study proposes mechanistic roles of breastmilk feeding and intestinal microbial colonization in postnatal intestinal barrier maturation; these observations are critical toward advancing therapeutics to prevent and treat hyperpermeable gut-associated conditions, including necrotizing enterocolitis (NEC). IMPORTANCE Despite improvements in neonatal intensive care, necrotizing enterocolitis (NEC) remains a leading cause of morbidity and mortality. "Leaky gut," or intestinal barrier immaturity with elevated intestinal permeability, is the proximate cause of susceptibility to NEC. Early detection and intervention to prevent leaky gut in "at-risk" preterm neonates are critical for decreasing the risk of potentially life-threatening complications like NEC. However, the complex interactions between the developing gut microbial community, nutrition, and intestinal barrier function remain largely uncharacterized. In this study, we reveal the critical role of a sufficient breastmilk feeding volume and the specialized carbohydrate metabolism capability of Bifidobacterium in the coordinated postnatal improvement of the intestinal barrier. Determining the clinical and microbial biomarkers that drive the intestinal developmental disparity will inform early detection and novel therapeutic strategies to promote appropriate intestinal barrier maturation and prevent NEC and other adverse health conditions in preterm infants.

Asthma is a common and ubiquitous chronic respiratory disease that is associated with airway inflammation and hyperreactivity resulting in airway obstruction. It is now accepted that asthma is controlled by a combination of host genetics and environment in a rather complex fashion; however, the link between sensing of the environment and development and exacerbation of allergic lung inflammation is unclear. Human populations expressing cosegregating D299G and T399I polymorphisms in the TLR4 gene are associated with a decreased risk for asthma in adults along with hyporesponsiveness to inhaled LPS, the TLR4 ligand. However, these data do not account for other human genetic or environmental factors. Using a novel mouse strain that expresses homologous human TLR4 polymorphisms (TLR4-single nucleotide polymorphism [SNP]), we directly tested the effect of these TLR4 polymorphisms on in vivo responses to allergens using two models of induction. We report that intact TLR4 is required for allergic inflammation when using the OVA and LPS model of induction, as cellular and pathological benchmarks were diminished in both TLR4-SNP and TLR4-deficent mice. However, in the more clinically relevant model using house dust mite extract for induction, responses were enhanced in the TLR4-SNP mice, as evidenced by greater levels of eosinophilic inflammation, Th2 cytokine production, and house dust mite-specific IgG1 production compared with wild-type mice; however, mucus production and airway hyperreactivity were not affected. These results suggest that the TLR4 polymorphic variants (genes) interact differently with the allergic stimulation (environment)., (Copyright © 2022 by The American Association of Immunologists, Inc.)

Intestinal barrier immaturity, or "leaky gut", is the proximate cause of susceptibility to necrotizing enterocolitis in preterm neonates. Exacerbated intestinal immune responses, gut microbiota dysbiosis, and heightened barrier injury are considered primary triggers of aberrant intestinal maturation in early life. Inordinate host immunity contributes to this process, but the precise elements remain largely uncharacterized, leaving a significant knowledge gap in the biological underpinnings of gut maturation. In this study, we investigated the fecal cytokine profile and gut microbiota in a cohort of 40 early preterm infants <33-weeks-gestation to identify immune markers of intestinal barrier maturation. Three distinct microbiota types were demonstrated to be differentially associated with intestinal permeability (IP), maternal breast milk feeding, and immunological profiles. The Staphylococcus epidermidis- and Enterobacteriaceae-predominant microbiota types were associated with an elevated IP, reduced breast milk feeding, and less defined fecal cytokine profile. On the other hand, a lower IP was associated with increased levels of fecal IL-1α/β and a microbiota type that included a wide array of anaerobes with expanded fermentative capacity. Our study demonstrated the critical role of both immunological and microbiological factors in the early development of intestinal barrier that collectively shape the intestinal microenvironment influencing gut homeostasis and postnatal intestinal maturation in early preterm newborns., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Lemme-Dumit, Song, Lwin, Hernandez-Chavez, Sundararajan, Viscardi, Ravel, Pasetti and Ma.)

Objective: This study aimed to determine the impact of neonatal intensive care unit (NICU) design and environmental factors on neonatal sound exposures. We hypothesized that monitoring with a smartphone application would identify modifiable environmental factors in different NICU design formats., Study Design: Minimum, maximum, and peak decibel (dB) recordings were obtained using the Decibel X phone app, and the presence of noise sources was recorded in each patient space at three NICUs over a 6-month period (December 2017 to May 2018). Data were analyzed by Student's t -test and ANOVA with Bonferroni correction. Data were collected at the University of Maryland Medical Center single family room (SFR) level IV and St. Agnes Healthcare hybrid pod/single family room level III NICU, Baltimore, MD and at Prince George's Hospital Center open-pod design Level III NICU, Cheverly, MD., Results: All recordings in the three NICUs exceeded the American Academy of Pediatrics (AAP) recommended <45 dB level. The maximum and peak dB were highest in the open pod format level III NICU. Conversations/music alone and combined with other factors contributed to increased sound exposure. Sound exposure varied by day/night shift, with higher day exposures at the level III hybrid and open pod NICUs and higher night exposures at the level IV SFR NICU., Conclusion: Although sound exposure varied by NICU design, all recordings exceeded the AAP recommendation due, in part, to potentially modifiable environmental factors. A smartphone application may be useful for auditing NICU sound exposure in quality improvements efforts to minimize environmental sound exposure., Key Points: · Smartphone application was used to assess NICU sound exposure.. · All cases of sound exposure exceed recommendations.. · A smartphone application was used to identify modifiable factors.., Competing Interests: None declared., (Thieme. All rights reserved.)

Background: To assess the potential impact of azithromycin treatment in the first week following birth on 2-year outcomes in preterm infants with and without Ureaplasma respiratory colonization who participated in a double-blind, placebo-controlled randomized controlled trial., Methods: Respiratory morbidity was assessed at NICU discharge and at 6, 12, and 22-26 months corrected age using pulmonary questionnaires. Comprehensive neurodevelopmental assessments were completed between 22 and 26 months corrected age. The primary and secondary composite outcomes were death or severe respiratory morbidity and death or moderate-severe neurodevelopmental impairment, respectively, at 22-26 months corrected age., Results: One hundred and twenty-one randomized participants (azithromycin, N = 60; placebo, N = 61) were included in the intent-to-treat analysis. There were no significant differences in death or serious respiratory morbidity (34.8 vs 30.4%, p = 0.67) or death or moderate-severe neurodevelopmental impairment (47 vs 33%, p = 0.11) between the azithromycin and placebo groups. Among all trial participants, tracheal aspirate Ureaplasma-positive infants experienced a higher frequency of death or serious respiratory morbidity at 22-26 months corrected age (58%) than tracheal aspirate Ureaplasma-negative infants (34%) or non-intubated infants (21%) (p = 0.028)., Conclusions: We did not observe strong evidence of a difference in long-term pulmonary and neurodevelopment outcomes in preterm infants treated with azithromycin in the first week of life compared to placebo., Impact: No strong evidence of a difference in long-term pulmonary and neurodevelopment outcomes was identified at 22-26 months corrected age in infants treated with azithromycin in the first week of life compared to placebo. The RCT is the first study of 2-year pulmonary and neurodevelopmental outcomes of azithromycin treatment in ELGANs. Provides evidence that ELGANs with lower respiratory tract Ureaplasma have the most frequent serious respiratory morbidity in the first 2 years of life, suggesting that a Phase III trial of azithromycin to prevent BPD targeting this population is warranted., (© 2021. The Author(s).)

Introduction: Neonatal intensive care unit (NICU) provider point-of-care ultrasound (POCUS) procedural competency for umbilical line placement confirmation has not been defined, and the necessary training to achieve competency has not been previously studied. This study's objective was to test the hypothesis that a simulation-enhanced curriculum will improve NICU providers' POCUS competency to confirm umbilical line placement., Methods: Neonatal intensive care unit providers without prior ultrasound experience were randomized to a curriculum with or without simulation-based training. Competency for catheter detection, tip localization, and scan interpretation on patients was determined using learning curve-cumulative summation, a specific statistical tool designed to indicate when a predefined level of performance is reached. Differences in success rates were analyzed by χ2 test., Results: Two thirds (22/33) of participants completed 10 scans. Three (simulation) and 1 (control) attained catheter detection competency (P = 0.28). The simulation group was more successful for catheter detection (81% vs. 69%, P = 0.04) and scan interpretation (61% vs. 48%, P = 0.04). Success did not differ by umbilical vessel location, provider role, or duration of NICU experience., Conclusions: A simulation-enhanced POCUS curriculum improved catheter detection rate and scan interpretation, but there was no difference in procedural competency between groups on ultrasound scans performed on patients with umbilical catheters. We speculate that more than 10 scans may be needed for NICU providers to obtain POCUS competency., Competing Interests: The authors declare no conflict of interest., (Copyright © 2020 Society for Simulation in Healthcare.)

Objective: Evaluate the association between carbon dioxide (pCO 2 ), cerebral blood flow (CBF), and cerebral autoregulation (CA) in preterm infants., Study Design: Cerebral saturations (rScO 2, surrogate for CBF using NIRS) and mean arterial blood pressure (MAP) monitored for 96 h in infants <29 weeks gestation. Relationship between rScO 2 , the rScO 2 -MAP correlation (CA analysis) and pCO 2 category assessed by mixed effects modeling., Results: Median pCO 2 differed by postnatal day (p < 0.0001)-pCO 2 increased between day 1 and 2, and low variability seen on day 4. A 5% increase in rScO 2 was noted when pCO 2 was >55 mmHg on each postnatal day (p < 0.001). No association observed between the overall rScO 2 -MAP correlation and pCO 2 . On day 1 only, the correlation coefficient decreased from 0.26 to -0.09 as pCO 2 category increased (p = 0.02)., Conclusions: CBF increased above a pCO 2 threshold of 55 mmHg, but overall, no association between pCO 2 and CA was noted.

Objective: To test whether azithromycin eradicates Ureaplasma from the respiratory tract in preterm infants., Design: Prospective, phase IIb randomised, double-blind, placebo-controlled trial., Setting: Seven level III-IV US, academic, neonatal intensive care units (NICUs)., Patients: Infants 24 0 -28 6 weeks' gestation (stratified 24 0 -26 6 ; 27 0 -28 6 weeks) randomly assigned within 4 days following birth from July 2013 to August 2016., Interventions: Intravenous azithromycin 20 mg/kg or an equal volume of D5W (placebo) every 24 hours for 3 days., Main Outcome Measures: The primary efficacy outcome was Ureaplasma -free survival. Secondary outcomes were all-cause mortality, Ureaplasma clearance, physiological bronchopulmonary dysplasia (BPD) at 36 weeks' postmenstrual age, comorbidities of prematurity and duration of respiratory support., Results: One hundred and twenty-one randomised participants (azithromycin: n=60; placebo: n=61) were included in the intent-to-treat analysis (mean gestational age 26.2±1.4 weeks). Forty-four of 121 participants (36%) were Ureaplasma positive (azithromycin: n=19; placebo: n=25). Ureaplasma -free survival was 55/60 (92% (95% CI 82% to 97%)) for azithromycin compared with 37/61 (61% (95% CI 48% to 73%)) for placebo. Mortality was similar comparing the two treatment groups (5/60 (8%) vs 6/61 (10%)). Azithromycin effectively eradicated Ureaplasma in all azithromycin-assigned colonised infants, but 21/25 (84%) Ureaplasma -colonised participants receiving placebo were culture positive at one or more follow-up timepoints. Most of the neonatal mortality and morbidity was concentrated in 21 infants with lower respiratory tract Ureaplasma colonisation. In a subgroup analysis, physiological BPD-free survival was 5/10 (50%) (95% CI 19% to 81%) among azithromycin-assigned infants with lower respiratory tract Ureaplasma colonisation versus 2/11 (18%) (95% CI 2% to 52%) in placebo-treated infants., Conclusion: A 3-day azithromycin regimen effectively eradicated respiratory tract Ureaplasma colonisation in this study., Trial Registration Number: NCT01778634., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: To test the hypothesis that impaired cerebral autoregulation (ICA) increases the susceptibility of premature infants to adverse outcomes, we determined the relationship of ICA and cerebral reactivity (CR) measured in the first 96 hours of life to the outcome of grade 3 or 4 intraventricular haemorrhage (IVH) and/or death within 1 month., Setting: Single-centre level IV neonatal intensive care unit., Patients: Neonates 24-29 weeks' gestation less than 12 hours old with invasive blood pressure monitoring., Design: Cerebral saturations and mean arterial blood pressure were recorded every 30 s for 96 hours. For each 10 min epoch, the correlation coefficient (r) was calculated for mean arterial blood pressure versus cerebral saturations. The epoch was considered to have ICA if r>0.5 and CR if r<0., Results: Sixty-one subjects were included. During the first 96 hours, ICA occurred 17.6% and CR occurred 41% of recorded time. In those without adverse outcomes, ICA decreased and CR increased by postnatal day (p<0.05). Adjusted for birth weight and gestational age, those with IVH and those who died spent more time with ICA and less time with CR (p<0.05) over the entire recording period. Those with IVH had 1.5-fold increase in time with ICA on day 2 (p=0.021), and decrease in time with CR on day 3 (p=0.036). Compared with survivors, non-survivors spent more time with ICA on days 3 and 4 (p<0.005), and less with CR on day 3 (p=0.032)., Conclusion: ICA and CR vary by postnatal day and these patterns are associated with adverse outcomes., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: To determine the relationships of red blood cell (RBC) transfusion and enteral feeding to changes in intestinal permeability (IP) measured by the relative intestinal uptake of lactulose (La) and rhamnose (Rh) in preterm infants <33 wk gestation., Design/methods: Infants 240-326wk gestation received La/Rh solution enterally on study days 1, 8 and 15.Urinary La/Rh ratio was measured by HPLC. Hematocrit preceding transfusion, total RBC transfusion volume, volume/kg, and feeding status during each study interval (birth-d1; d1-d8, and d8-d15) were determined., Results: Of the seventeen (40.5%) subjects who received≥1 transfusion during the study period, 12 (70.6%) infants were <28 wk gestation and 5 (29.4%) infants were≥28 wk gestation, p < 0.0001. Lower pre-transfusion hematocrit was observed in intervals preceding high IP (La/Rh > 0.05) than in intervals preceding low IP (La/Rh≤0.05) measurements (33 vs 35.8, p = 0.1051). RBC transfusions occurred more frequently in intervals preceding high IP than in intervals preceding low IP (26.8%; vs 8.3%, p = 0.0275) with 5-fold higher total RBC volume and volume/kg in intervals preceding any time point with high IP. RBC transfusion during an interval was associated with a three-fold increased risk of high IP (aOR 2.7; 95% C.I 0.564-12.814; p = 0.2143). Exclusive breast milk exposure and post-menstrual age reduced the risk for high IP following RBC transfusion., Conclusions: Both RBC transfusion number and volume was associated with subsequent high IP measurements in preterm infants <33 weeks gestation and potentially may contribute to impairment of the preterm intestinal barrier.

Intestinal barrier immaturity, or "leaky gut," is the proximate cause of susceptibility to necrotizing enterocolitis in preterm neonates. However, the impact of intestinal microbiota development on intestinal mucosal barrier maturation has not been evaluated in this population. In this study, we investigated a longitudinally sampled cohort of 38 preterm infants < 33 weeks gestation monitored for intestinal permeability (IP) and fecal microbiota during the first 2 weeks of life. Rapid decrease in IP indicating intestinal barrier function maturation correlated with significant increase in community diversity. In particular, members of the Clostridiales and Bifidobacterium were highly transcriptionally active, and progressively increasing abundance in Clostridiales was significantly associated with decreased intestinal permeability. Further, neonatal factors previously identified to promote intestinal barrier maturation, including early exclusive breastmilk feeding and shorter duration antibiotic exposure, associate with the early colonization of the intestinal microbiota by members of the Clostridiales, which altogether are associated with improved intestinal barrier function in preterm infants.

Objective: To test the hypothesis that feeding and antibiotic exposures affect intestinal barrier maturation in preterm infants, we serially measured intestinal permeability (IP) biomarkers in infants <33 weeks gestation (gestational age [GA]) during the first 2 weeks of life., Study Design: Eligible infants <33 weeks GA were enrolled within 4 days of birth in a prospective study of IP biomarkers (NCT01756040). Study participants received the nonmetabolized sugars lactulose/rhamnose enterally on study days 1, 8, and 15 and lactulose/rhamnose were measured in urine by high-performance liquid chromatography. Serum zonulin and fecal alpha-1-anti-trypsin, 2 other IP markers, were measured by semiquantitative Western blot and ELISA, respectively., Results: In a cohort of 43 subjects, the lactulose/rhamnose ratio was increased on day 1 and decreased over 2 weeks, but remained higher in infants born at ≤28 weeks of gestation compared with IP in infants born at >28 weeks of gestation. Exclusive breastmilk feeding was associated with more rapid maturation in intestinal barrier function. A cluster analysis of 35 subjects who had urine samples from all time points revealed 3 IP patterns (cluster 1, normal maturation: n = 20 [57%]); cluster 2, decreased IP during the first week and subsequent substantial increase: n = 5 [14%]); and cluster 3, delayed maturation: n = 10 [29%]). There were trends toward more prolonged antibiotic exposure (P = .092) and delayed initiation of feeding ≥4 days (P = .064) in infants with abnormal IP patterns., Conclusions: Intestinal barrier maturation in preterm infants is GA and postnatal age dependent, and is influenced by feeding with a maturational effect of breastmilk feeding and possibly by antibiotic exposures., Trial Registration: ClinicalTrials.gov: NCT01756040., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Preterm infants often require some form of respiratory support with supplemental oxygen and are monitored by continuous pulse oximetry (SpO2 ). The study objective was to determine whether the histogram distribution of SpO2 over a 24-h period will predict readiness for weaning respiratory support in preterm infants. We hypothesize that infants with ≥15% of time spent with SpO2 <86% before transitioning from CPAP or high-flow nasal cannula (HFNC) to low-flow nasal cannula, oxyhood, or room air are more likely to fail transitioning., Methods: The SpO2 histograms were downloaded daily for 31 infants, 24-32 weeks gestational age, before transition from CPAP or HFNC to low-flow nasal cannula, oxyhood, or room air. The SpO2 histogram downloads were continued for each infant for 1 week after transition or when the infant reached 36 weeks postmenstrual age or when SpO2 monitoring was discontinued. Failure was defined as an increase in respiratory support within 72 h of transitioning. We compared the percentage of time for each SpO2 quintile for the 24-h periods before and immediately following CPAP/HFNC transitioning between groups., Results: Twenty-four subjects transitioned successfully, but 7 subjects failed. Two of 7 subjects (28.6%) who failed transition experienced SpO2 <86% ≥15% of the time pretransition compared with none in the success group (P = .045). The failure group experienced SpO2 <86% 10.7 ± 11.9% of time pre-wean compared with 3.3 ± 4.7% of time in the success group (P = .02). In contrast, infants who were successfully weaned tended to experience a greater percentage of time with SpO2 >95% compared with the failure group, both pre-wean (54.3 ± 36.1% vs. 33 ± 27.7%, P = .16) and post-wean (52 ± 35.4% vs. 27.4 ± 27.7%, P = .10)., Conclusions: These data suggest that pulse oximetry histograms may be useful in assessing CPAP/HFNC support transition readiness., (Copyright © 2016 by Daedalus Enterprises.)

Objective: The objective of this study was to characterise the effects of antenatal inflammatory factors and maternal therapies on neonatal hearing screen outcomes in very low birthweight infants., Methods: We conducted a retrospective study of a cohort of infants <33 weeks' gestational age and <1501 g birth weight prospectively enrolled between 1999 and 2003 for whom placental pathology, cord blood interleukin (IL) 6, IL-1ß, tumour necrosis factor-α and neonatal hearing screen results were available., Results: Of 289 infants with documented hearing screen results, 244 (84%) passed and 45 (16%) failed the hearing screen (unilateral, N=25 (56%); bilateral, N=20 (44%)). In the final logistic model, the fetal inflammatory response syndrome defined as the presence of fetal vasculitis and/or cord serum IL-6>18.2 pg/mL was the factor with greatest risk for hearing screen failure (OR 3.62, 95% CI 1.38 to 9.5). A patent ductus arteriosus treated with indomethacin significantly increased the risk (OR 3.3, 95% CI 1.3 to 8.26), while combined maternal steroid and magnesium sulfate exposure (0.37, 95% CI 0.11 to 0.81) reduced the risk for hearing screen failure., Conclusions: Intrauterine infection with a fetal inflammatory response is a risk factor for neonatal hearing loss while maternal therapies significantly reduced the risk of neonatal hearing loss in very low birthweight infants., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

Respiratory tract colonization with the genital mycoplasma species Ureaplasma parvum and Ureaplasma urealyticum in preterm infants is a significant risk factor for bronchopulmonary dysplasia (BPD). Recent studies of the ureaplasmal genome, animal infection models, and human infants have provided a better understanding of specific virulence factors, pathogen-host interactions, and variability in genetic susceptibility that contribute to chronic infection, inflammation, and altered lung development. This review provides an update on the current evidence supporting a causal role of ureaplasma infection in BPD pathogenesis. The current status of antibiotic trials to prevent BPD in Ureaplasma-infected preterm infants is also reviewed., (Copyright © 2015 Elsevier Inc. All rights reserved.)

The study objectives were to refine the population pharmacokinetics (PK) model, determine microbial clearance, and assess short-term pulmonary outcomes of multiple-dose azithromycin treatment in preterm infants at risk for Ureaplasma respiratory colonization. Fifteen subjects (7 of whom were Ureaplasma positive) received intravenous azithromycin at 20 mg/kg of body weight every 24 h for 3 doses. Azithromycin concentrations were determined in plasma samples obtained up to 168 h post-first dose by using a validated liquid chromatography-tandem mass spectrometry method. Respiratory samples were obtained predose and at three time points post-last dose for Ureaplasma culture, PCR, antibiotic susceptibility testing, and cytokine concentration determinations. Pharmacokinetic data from these 15 subjects as well as 25 additional subjects (who received either a single 10-mg/kg dose [n = 12] or a single 20-mg/kg dose [n = 13]) were analyzed by using a nonlinear mixed-effect population modeling (NONMEM) approach. Pulmonary outcomes were assessed at 36 weeks post-menstrual age and 6 months adjusted age. A 2-compartment model with all PK parameters allometrically scaled on body weight best described the azithromycin pharmacokinetics in preterm neonates. The population pharmacokinetics parameter estimates for clearance, central volume of distribution, intercompartmental clearance, and peripheral volume of distribution were 0.15 liters/h · kg(0.75), 1.88 liters · kg, 1.79 liters/h · kg(0.75), and 13 liters · kg, respectively. The estimated area under the concentration-time curve over 24 h (AUC24)/MIC90 value was ∼ 4 h. All posttreatment cultures were negative, and there were no drug-related adverse events. One Ureaplasma-positive infant died at 4 months of age, but no survivors were hospitalized for respiratory etiologies during the first 6 months (adjusted age). Thus, a 3-day course of 20 mg/kg/day intravenous azithromycin shows preliminary efficacy in eradicating Ureaplasma spp. from the preterm respiratory tract., (Copyright © 2015, American Society for Microbiology. All Rights Reserved.)

Neonatal hypoglycaemia can lead to devastating consequences. Thus, constant, accurate and safe glucose monitoring is imperative in neonatal care. However, point-of-care (POC) devices for glucose testing currently used for neonates were originally designed for adults and do not address issues specific to neonates. This review will address currently available monitoring options and describe new methodologies for non-invasive glucose monitoring in newborns.

The genital mycoplasma species, Ureaplasma parvum and Ureaplasma urealyticum are the most common organisms isolated from infected amniotic fluid and placentas, and they contribute to adverse pregnancy outcomes including preterm birth and neonatal morbidities. In our institution, almost half of the preterm infants of less than 32 weeks gestation are Ureaplasma-positive in one or more compartment (respiratory, blood and/or cerebrospinal fluid), indicating that these organisms are the most common pathogens affecting this population. This review will focus on the compelling epidemiological and experimental evidence linking perinatal Ureaplasma species exposure to important morbidities of prematurity, such as bronchopulmonary dysplasia, intraventricular haemorrhage and necrotising enterocolitis.

Background: Ureaplasma spp. respiratory tract colonization is a risk factor for bronchopulmonary dysplasia (BPD) in preterm infants, but differences in host susceptibility have not been elucidated. We hypothesized that variants in genes regulating the innate immune response are associated with altered risk for Ureaplasma spp. respiratory colonization and BPD in preterm infants., Methods: Twenty-four tag single nucleotide polymorphisms (SNPs) from Toll-like receptor (TLR)1, TLR2, TLR4 and TLR6 were assayed in 298 infants <33 weeks gestation who had serial respiratory cultures for Ureaplasma spp. and were evaluated for BPD., Results: The majority of subjects (N = 205 [70%]) were African-American. One hundred ten (37%) were Ureaplasma positive. Four SNPs in TLR2 and TLR6 were significantly associated with Ureaplasma respiratory tract colonization. Single SNPs in TLR2, TLR4 and TLR6 were associated with BPD. TLR6 SNP rs5743827 was associated with both a decreased risk for Ureaplasma respiratory tract colonization and decreased risk for BPD (odds ratio: 0.54 [0.34-0.86] and odds ratio: 0.54 [0.31-0.95], respectively). There was a significant additive interaction between Ureaplasma colonization and genotype at TLR6 SNP rs5743827 (Padditive = 0.023), with an attributable proportion due to interaction of 0.542., Conclusions: Polymorphisms in host defense genes may alter susceptibility to Ureaplasma infection and severity of the inflammatory response contributing to BPD. These observations implicate host genetic susceptibility as a major factor in BPD pathogenesis in Ureaplasma-infected preterms.

Ureaplasma respiratory tract colonization is associated with bronchopulmonary dysplasia (BPD) in preterm infants. Previously, we demonstrated that a single intravenous (i.v.) dose of azithromycin (10 mg/kg of body weight) is safe but inadequate to eradicate Ureaplasma spp. in preterm infants. We performed a nonrandomized, single-arm open-label study of the pharmacokinetics (PK) and safety of intravenous 20-mg/kg single-dose azithromycin in 13 mechanically ventilated neonates with a gestational age between 24 weeks 0 days and 28 weeks 6 days. Pharmacokinetic data from 25 neonates (12 dosed with 10 mg/kg i.v. and 13 dosed with 20 mg/kg i.v.) were analyzed using a population modeling approach. Using a two-compartment model with allometric scaling of parameters on body weight (WT), the population PK parameter estimates were as follows: clearance, 0.21 liter/h × WT(kg)(0.75) [WT(kg)(0.75) indicates that clearance was allometrically scaled on body weight (in kilograms) with a fixed exponent of 0.75]; intercompartmental clearance, 2.1 liters/h × WT(kg)(0.75); central volume of distribution (V), 1.97 liters × WT (kg); and peripheral V, 17.9 liters × WT (kg). There was no evidence of departure from dose proportionality in azithromycin exposure over the tested dose range. The calculated area under the concentration-time curve over 24 h in the steady state divided by the MIC90 (AUC24/MIC90) for the single dose of azithromycin (20 mg/kg) was 7.5 h. Simulations suggest that 20 mg/kg for 3 days will maintain azithromycin concentrations of >MIC50 of 1 μg/ml for this group of Ureaplasma isolates for ≥ 96 h after the first dose. Azithromycin was well tolerated with no drug-related adverse events. One of seven (14%) Ureaplasma-positive subjects and three of six (50%) Ureaplasma-negative subjects developed physiologic BPD. Ureaplasma was eradicated in all treated Ureaplasma-positive subjects. Simulations suggest that a multiple-dose regimen may be efficacious for microbial clearance, but the effect on BPD remains to be determined.

Background: Ureaplasma respiratory tract colonization is a risk factor for bronchopulmonary dysplasia (BPD) in preterm infants, but whether Ureaplasma isolates from colonized infants can form biofilms is unknown. We hypothesized that Ureaplasma isolates vary in capacity to form biofilms that contribute to their antibiotic resistance and ability to evade host immune responses. Study objectives were to (1) determine the ability of Ureaplasma isolates from preterm neonates to form biofilms in vitro; (2) compare the susceptibility of the sessile and planktonic organisms to azithromycin (AZI) and erythromycin; and (3) determine the relationship of biofilm-forming capacity in Ureaplasma isolates and the risk for BPD., Methods: Forty-three clinical isolates from preterm neonates and 5 American Tissue Culture Collection strains were characterized for their capacity to form biofilms in vitro, and antibiotic susceptibility was performed on each isolate prebiofilm and postbiofilm formation., Results: Forty-one (95%) clinical and 4 of 5 (80%) American Tissue Culture Collection isolates formed biofilms. All isolates were more susceptible to AZI (minimum inhibitory concentration, MIC50 2 µg/mL) than erythromycin (MIC50 4 µg/mL), and biofilm formation did not significantly affect antibiotic susceptibility for the 2 tested antibiotics. The MIC50 and minimum biofilm inhibitory concentrations (MBIC50) for Ureaplasma urealyticum clinical isolates for AZI were higher than for MIC50 and MBIC50 for Ureaplasma parvum isolates. There were no differences in MIC or MBICs among isolates from BPD infants and non-BPD infants., Conclusions: Capacity to form biofilms is common among Ureaplasma spp. isolates, but biofilm formation did not impact MICs for AZI or erythromycin.

Background: Our motivation for this study was to develop a noninvasive glucose sensor for low birth weight neonates. We hypothesized that the underdeveloped skin of neonates will allow for the diffusion of glucose to the surface where it can be sampled noninvasively. On further study, we found that measurable amounts of glucose can also be collected on the skin of adults., Method: Cellulose acetate dialysis membrane was used as surrogate for preterm neonatal skin. Glucose on the surface was collected by saline-moistened swabs and analyzed with glucose-binding protein (GBP). The saline-moistened swab was also tested in the neonatal intensive care unit. Saline was directly applied on adult skin and collected for analysis with two methods: GBP and high-performance anion-exchange chromatography (HPAEC)., Results: The amount of glucose on the membrane surface was found (1) to accumulate with time but gradually level off, (2) to be proportional to the swab dwell time, and (3) the concentration of the glucose solution on the opposite side of the membrane. The swab, however, failed to absorb glucose on neonatal skin. On direct application of saline onto adult skin, we were able to measure by HPAEC and GBP the amount of glucose collected on the surface. Blood glucose appears to track transdermal glucose levels., Conclusions: We were able to measure trace amounts of glucose on the skin surface that appear to follow blood glucose levels. The present results show modest correlation with blood glucose. Nonetheless, this method may present a noninvasive alternative to tracking glucose trends., (© 2013 Diabetes Technology Society.)

Mycoplasma and Ureaplasma species are well-known human pathogens responsible for a broad array of inflammatory conditions involving the respiratory and urogenital tracts of neonates, children, and adults. Greater attention is being given to these organisms in diagnostic microbiology, largely as a result of improved methods for their laboratory detection, made possible by powerful molecular-based techniques that can be used for primary detection in clinical specimens. For slow-growing species, such as Mycoplasma pneumoniae and Mycoplasma genitalium, molecular-based detection is the only practical means for rapid microbiological diagnosis. Most molecular-based methods used for detection and characterization of conventional bacteria have been applied to these organisms. A complete genome sequence is available for one or more strains of all of the important human pathogens in the Mycoplasma and Ureaplasma genera. Information gained from genome analyses and improvements in efficiency of DNA sequencing are expected to significantly advance the field of molecular detection and genotyping during the next few years. This review provides a summary and critical review of methods suitable for detection and characterization of mycoplasmas and ureaplasmas of humans, with emphasis on molecular genotypic techniques., (Copyright © 2012 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.)

Bronchopulmonary dysplasia (BPD) remains the major morbidity of extreme preterm birth. The incidence of BPD has remained stable despite recent efforts to reduce postnatal exposures to volutrauma and hyperoxia. This review will focus on recent clinical and experimental insights that provide support for the concept that the 'new BPD' is the result of inflammation-mediated injury and altered lung development during a window of vulnerability in genetically susceptible infants that is modified by maternal and postnatal exposures., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Introduction: The genetic contribution to the development of bronchopulmonary dysplasia (BPD) in prematurely born infants is substantial, but information related to the specific genes involved is lacking., Results: Genotype analysis revealed, after multiple comparisons correction, two significant single-nucleotide polymorphism (SNPs), rs3771150 (IL-18RAP) and rs3771171 (IL-18R1), in African Americans (AAs) with BPD (vs. AAs without BPD; q < 0.05). No associations with Caucasian (CA) BPD, AA or CA respiratory distress syndrome (RDS), or prematurity in either AAs or CAs were identified with these SNPs. Respective frequencies were 0.098 and 0.093 in infants without BPD and 0.38 for each SNP in infants with BPD. In the replication set (82 cases; 102 controls), the P values were 0.012 for rs3771150 and 0.07 for rs3771171. Combining P values using Fisher's method, overall P values were 8.31 × 10(-7) for rs3771150 and 6.33 × 10(-6) for rs3771171., Discussion: We conclude that IL-18RAP and IL-18R1 SNPs identify AA infants at risk for BPD. These genes may contribute to AA BPD pathogenesis via inflammatory-mediated processes and require further study., Methods: We conducted a case-control SNP association study of candidate genes (n = 601) or 6,324 SNPs in 1,091 prematurely born infants with gestational age <35 weeks, with or without neonatal lung disease including BPD. BPD was defined as a need for oxygen at 28 days.

Objective: To determine whether neonatal intensive care unit (NICU) admission hypothermia is associated with an intrauterine inflammatory response., Methods: We analyzed a cohort of 309 very low birthweight infants to determine relationships between admission hypothermia, chorioamnionitis, and serum and cerebrospinal fluid (CSF) interleukin (IL)-1β, IL-6, and tumor necrosis factor-α., Results: Admission hypothermia <36°C occurred in 72% of patients <26 weeks and 44% of patients ≥26 weeks gestational age. NICU admission hypothermia was not associated with histologic chorioamnionitis or with elevated serum cytokine concentrations. CSF IL-6 concentrations ≥6.3 pg/mL were associated with admission hypothermia in infants <26 weeks' gestation. Clinical chorioamnionitis was associated with a lower risk of admission hypothermia, while cesarean section delivery was associated with increased risk., Conclusions: NICU admission hypothermia is common among preterm infants and is not associated with the fetal inflammatory response syndrome. Hypothermia is less common in the setting of clinical chorioamnionitis and more common in cesarean section deliveries, identifying two groups in whom extra attention to appropriate thermoregulation is warranted.

Immunization with Ft-LPS provokes an antigen-specific, B-1a cell-derived antibody response that protects WT mice against an otherwise lethal challenge with Ft LVS. However, this same regimen offers limited protection to TLR2(-/-) mice, despite production of WT levels of anti-Ft-LPS antibodies. As Ft-LPS exhibits no TLR2 agonist activity, and macrophage-induced cytokine production in response to Ft LVS is overwhelmingly TLR2-dependent, we hypothesized that treatment of TLR2(-/-) mice with an alternative, MyD88-dependent TLR agonist would compensate for reduced recognition of Ft LVS in TLR2(-/-) mice and thereby, restore Ft-LPS-mediated protection. Administration of the nontoxic TLR4 agonist, synthetic Escherichia coli MPL, at the time of Ft-LPS immunization or Ft LVS challenge, fully protected TLR2(-/-) mice, whereas treatment of WT or TLR2(-/-) mice with MPL alone conferred partial protection. The TLR5 agonist, flagellin, also synergized with Ft-LPS to protect TLR2(-/-) mice from lethal Ft LVS challenge. In contrast to Ft LVS, Ft-LPS pretreatment failed to protect mice against i.n. challenge with Ft Schu S4, whereas MPL, administered in the absence or presence of Ft-LPS, conferred significant, albeit partial, protection. MPL treatment of macrophages increased the uptake of Ft LVS and decreased intracellular bacterial survival while shifting the macrophage-differentiation phenotype from "alternatively activated" to "classically activated". Collectively, our data suggest that optimal, Ft-LPS-mediated protection against Ft LVS infection requires two discrete events, i.e., production of Ft-LPS-specific antibody, as well as TLR-mediated macrophage activation, to fully control Francisella infection.

Ureaplasma spp. respiratory tract colonization is a significant risk factor for bronchopulmonary dysplasia (BPD), a chronic lung disorder in preterm infants. As an initial step preparatory to future clinical trials to evaluate the clinical efficacy of azithromycin to prevent BPD, the authors characterized the pharmacokinetics, safety, and biological effects of a single intravenous dose of azithromycin (10 mg/kg) in preterm neonates (n = 12) 24 to 28 weeks gestation at risk for Ureaplasma infection and BPD. A 2-compartment structural model with the clearance and volume of peripheral compartment (V2) allometrically scaled on body weight (WT) best described the pharmacokinetics of azithromycin in preterm neonates. The estimated parameters were clearance [0.18 L/h × WT(kg)(0.75)], intercompartmental clearance [1.0 L/h], volume of distribution of central compartment [0.93 L], and V2 [14.2 L × WT(kg)]. There were no serious adverse events attributed to azithromycin. A single dose of azithromycin did not suppress inflammatory cytokines or myeloperoxidase activity in tracheal aspirates. These results demonstrated the safety of azithromycin and developed a pharmacokinetic model that is useful for future simulation-based clinical trials for eradicating Ureaplasma and preventing BPD in preterm neonates.

Objective: Ureaplasma respiratory tract colonization is associated with bronchopulmonary dysplasia (BPD) in preterm infants. Whether the 4 Ureaplasma parvum and 10 Ureaplasma urealyticum serovars differ in virulence is unknown. This study was conducted to determine the distribution of Ureaplasma serovars in respiratory secretions of a prospective cohort of preterm infants and to assess whether any of the serovars are associated with BPD., Methods: Serial endotracheal and/or nasopharyngeal aspirates were obtained for Ureaplasma culture and PCR from 136 infants of gestational age <33 weeks. All positive samples were speciated and serovars were determined by real-time PCR., Results: A total of 51 (37.5%) infants were Ureaplasma-positive one or more times during the first month of life. Respiratory colonization was inversely related to gestational age. Sixty-five percent of infants <26 weeks compared with 31% infants ≥ 26 weeks were culture or PCR positive. U. parvum was more common (N = 32, 63%) than U. urealyticum (N = 17, 33%); both species were present in 2 samples. Serovars 3 and 6 alone and in combination accounted for 96% U. parvum isolates. U. urealyticum isolates were commonly a mixture of multiple serovars, with serovar 11 alone or combined with other serovars (10/17, 59%) being the most common serovar. No individual species or serovars or serovar mixtures were associated with moderate-to-severe BPD., Conclusions: U. parvum serovars 3 and 6 and U. urealyticum serovar 11 were the most common serovars detected in respiratory samples from a prospective cohort of preterm infants.

The study objective was to determine whether Ureaplasma respiratory tract colonization of preterm infants <33 wk gestation is associated with an increased risk for necrotizing enterocolitis (NEC). One or more tracheal or nasopharyngeal aspirates for Ureaplasma culture and PCR were obtained during the first week of life from 368 infants <33 wk gestation enrolled from 1999 to 2003 or from 2007 to 2009. NEC Bell stage ≥ 2 was confirmed by radiological criteria, and pathology, if available. Cord serum samples were analyzed for IL-6 and IL-1β concentrations, and placentas were reviewed for histological chorioamnionitis in the first cohort. NEC was confirmed in 29 of 368 (7.9%) of the combined cohorts. The incidence of NEC was 2.2-fold higher in Ureaplasma-positive (12.3%) than Ureaplasma-negative (5.5%) infants <33 wk (OR, 2.43; 95% CI, 1.13-5.2; p = 0.023) and 3.3-fold higher in Ureaplasma-positive (14.6%) than Ureaplasma-negative (4.4%) infants ≤ 28 wk (OR, 3.67; 95% CI, 1.36-9.93; p = 0.01). Age of onset, hematologic parameters at onset, and NEC severity were similar between Ureaplasma-positive and negative infants. Cord serum IL-6 and IL-1β concentrations were significantly higher in Ureaplasma-positive than in Ureaplasma-negative NEC-affected infants. Ureaplasma may be a factor in NEC pathogenesis in preterm infants by contributing to intestinal mucosal injury and/or altering systemic or local immune responses.

Background: Persistent respiratory tract colonization with Ureaplasma spp. in preterm infants is a significant risk factor for the development of the chronic lung disorder, bronchopulmonary dysplasia (BPD). Surfactant protein-A (SP-A), a lung collectin critical for bacterial clearance and regulating inflammation, is deficient in the preterm lung. In an experimental Ureaplasma-pneumonia model, infected SP-A deficient mice exhibited delayed bacterial clearance and an exaggerated inflammatory response compared to infected wild-type mice. The objective was to analyze the role of SP-A in Ureaplasma clearance in vitro., Subjects and Methods: We analyzed SP-A binding to Ureaplasma isolates and SP-A-mediated ureaplasmal phagocytosis and killing by cultured RAW 264.7 macrophages., Results: Calcium-dependent SP-A binding was similar among Ureaplasma isolates tested. Pre-incubation of RAW 264.7 cells with SP-A (10-50 μg/ml) enhanced phagocytosis of fluorescein-isothiocyanate (FITC)-labeled Ureaplasma. Surfactant protein-A also increased ureaplasmacidal activity of RAW 264.7 cells by 2.1-fold over 4 h. Pre-incubation of RAW 264.7 cells with 10 μg/ml SP-A reduced lipopolysaccharide (LPS) (100 ng/ml) and Ureaplasma (10(6) color changing units/ml)-stimulated release of tumor necrosis factor-α (TNF-α) by 46% and 43%, respectively, but did not affect transforming growth factor β(1) (TGFβ(1)) release., Conclusions: These in vitro data confirm that SP-A is important in host defense to perinatally-acquired Ureaplasma infection.

There is accumulating epidemiologic and experimental evidence that intrauterine or postnatal infection with Ureaplasma species is a significant risk factor for adverse pregnancy outcomes and complications of extreme preterm birth such as bronchopulmonary dysplasia and intraventricular hemorrhage. In a cohort of very low birth weight infants, Ureaplasma spp were detected by culture or polymerase chain reaction in respiratory secretions, blood, or cerebrospinal fluid of almost half of the subjects, suggesting that this organism is the most common pathogen affecting this population. This review summarizes the evidence supporting the hypothesis that Ureaplasma-mediated inflammation in different compartments (intrauterine, lung, blood, or brain) during a common developmental window of vulnerability contributes to preterm labor and lung and brain injury. Appropriate methods for detecting these fastidious organisms and potential strategies to prevent or ameliorate the effects of Ureaplasma infection are discussed.

Ureaplasma respiratory tract colonization stimulates prolonged, dysregulated inflammation in the lungs of preterm infants, contributing to bronchopulmonary dysplasia (BPD) pathogenesis. Surfactant protein-A (SP-A), a lung collectin critical for bacterial clearance and regulating inflammation, is deficient in the preterm lung. To analyze the role of SP-A in modulating Ureaplasma-mediated lung inflammation, SP-A deficient (SP-A-/-) and WT mice were inoculated intratracheally with a mouse-adapted U. parvum isolate and indices of inflammation were sequentially assessed up to 28 d postinoculation. Compared with infected WT and noninfected controls, Ureaplasma-infected SP-A-/- mice exhibited an exaggerated inflammatory response evidenced by rapid influx of neutrophils and macrophages into the lung, and higher bronchoalveolar lavage TNF-alpha, mouse analogue of human growth-related protein alpha (KC), and monocyte chemotactic factor (MCP-1) concentrations. However, nitrite generation in response to Ureaplasma infection was blunted at 24 h and Ureaplasma clearance was delayed in SP-A-/- mice compared with WT mice. Coadministration of human SP-A with the Ureaplasma inoculum to SP-A-/- mice reduced the inflammatory response, but did not improve the bacterial clearance rate. SP-A deficiency may contribute to the prolonged inflammatory response in the Ureaplasma-infected preterm lung, but other factors may contribute to the impaired Ureaplasma clearance.

The contribution of Ureaplasma respiratory tract colonization to the pathogenesis of bronchopulmonary dysplasia in preterm infants has been debated for over 20 y. We review the current understanding of the role of inflammation in altered developmental signaling in the preterm lung and the evidence from human studies and experimental models that Ureaplasma-mediated inflammation produces the BPD phenotype. We propose that Ureaplasma infection initiated in utero and augmented postnatally by exposure to volutrauma and oxygen elicits a sustained, dysregulated inflammatory response in the immature lung that impairs alveolarization, and stimulates myofibroblast proliferation and excessive collagen and elastin deposition. Potential strategies to prevent or ameliorate the effects of Ureaplasma infection in utero and in the preterm lung are discussed.

Objectives: To evaluate the relationship between fetal Doppler parameters, biophysical profile score (BPP) and neurodevelopmental delay at 2 years of corrected age in infants who had been growth-restricted in utero., Methods: This was a prospective observational study including 113 pregnancies complicated by intrauterine growth restriction (IUGR) (abdominal circumference<5th percentile and elevated umbilical artery (UA) pulsatility index). The relationships of UA, middle cerebral artery and ductus venosus (DV) Doppler features, BPP, birth acidemia (artery pH<7.0+/or base deficit>12), gestational age at delivery, birth weight and neonatal morbidity (i.e. bronchopulmonary dysplasia, >Grade 2 intraventricular hemorrhage, or necrotizing enterocolitis) with a 2-year neurodevelopmental delay were evaluated. Best Beginnings Developmental Screen, Bayley Scale of Infant Development II (BSID) and Clinical Adaptive/Clinical Linguistic Auditory Milestone Stage were used. BSID<70, cerebral palsy, abnormal tone, hearing loss and/or blindness defined neurodevelopmental delay., Results: Seventy-two of the 113 pregnancies completed assessment; there were 10 stillbirths, 19 neonatal deaths, three infant deaths and nine pregnancies with no follow-up. Twenty fetuses (27.8%) had UA reversed end-diastolic velocity (REDV), 34 (47.2%) abnormal DV Doppler features and 31 (43.1%) an abnormal BPP. Median gestational age at delivery and birth weight were 30.4 weeks and 933 g, respectively. Twelve infants had acidemia and 28 neonatal morbidity. There were 38 (52.8%) infants with neurodevelopmental delay, including 37 (51.4%) with abnormal tone, 20 (27.8%) with speech delay, 23 (31.9%) with an abnormal neurological examination, eight (11.1%) with a hearing deficit and six (8.3%) with cerebral palsy. Gestational age at delivery was associated with cerebral palsy (r2=0.52, P<0.0001; 92% sensitivity and 83% specificity for delivery at <27 weeks). UA-REDV was associated with global delay (r2=0.31, P=0.006) and birth weight with neurodevelopmental delay (r2=0.54, P<0.0001; 82% sensitivity and 64% specificity for BW<922 g)., Conclusions: Although UA-REDV is an independent contributor to poor neurodevelopment in IUGR no such effect could be demonstrated for abnormal venous Doppler findings or BPP. Gestational age and birth weight remain the predominant factors for poor neurodevelopment in growth-restricted infants., (Copyright (c) 2008 ISUOG.)

Objective: As Ureaplasmas may be pathogens in preterm infants, this study was conducted to determine the incidence of invasive disease with Ureaplasma parvum and Ureaplasma urealyticum and the relationship with adverse outcomes in a prospective cohort of very low birth weight (VLBW) infants., Study Design: DNA was extracted from the cord or venous blood and cerebrospinal fluid (CSF) samples obtained from 313 VLBW infants. PCR was performed using primers for the mba gene to detect all 14 serovars and then repeated for all positive samples using species-specific primers., Result: Ureaplasma species were detected in serum and/or CSF samples from 74 of 313 (23.6%) infants. U. parvum was the predominant species (70%). Presence of Ureaplasma was significantly associated with elevated interleukin-1beta in cord blood (odds ratio (OR) 2.6, 1.05 to 6.45, P=0.039). Ureaplasma serum-positive infants had a 2.3-fold increased risk of intraventicular hemorrhage > or =grade 3 (OR 2.50; 1.06 to 5.89, P=0.036)., Conclusion: Invasive Ureaplasma occurs commonly in VLBW infants and may increase the risk for severe intraventricular hemorrhage.

Chronic inflammation and fibrosis are hallmarks of lung pathology of newborn Ureaplasma infection. We hypothesized that antenatally acquired Ureaplasma stimulates a chronic inflammatory, profibrotic immune response that contributes to lung injury, altered developmental signaling, and fibrosis. Lung specimens from 125-d gestation baboon newborns ventilated for 14 d that were either infected antenatally with Ureaplasma serovar 1 or noninfected, and 125-d and 140-d gestational controls were obtained from the Baboon BPD Resource Center (San Antonio, TX). Trichrome stain to assess fibrosis and immunohistochemistry for alpha-smooth muscle actin (alpha-SMA) and transforming growth factor beta1 (TGFbeta1) were performed. Lung homogenates were analyzed by enzyme-linked immunosorbent assay (ELISA) for cytokines [tumor necrosis factor alpha (TNFalpha), interleukin (IL)-1beta, TGFbeta1, oncostatin M (OSM), IL-10, and interferon gamma (IFNgamma)] and the chemokine MCP-1 and by Western blot for Smad2, Smad3, and Smad7. Compared with noninfected ventilated and gestational controls, Ureaplasma-infected lungs demonstrated more extensive fibrosis, increased alpha-SMA and TGFbeta1 immunostaining, and higher concentrations of active TGFbeta1, IL-1beta, and OSM, but no difference in IL-10 levels. There was a trend toward higher Smad2/Smad7 and Smad3/Smad7 ratios in Ureaplasma lung homogenates, consistent with up-regulation of TGFbeta1 signaling. Collectively, these data suggest that a prolonged proinflammatory response initiated by intrauterine Ureaplasma infection contributes to early fibrosis and altered developmental signaling in the immature lung.

While moderate hypothermia is protective against ischemic cardiac and brain injury, it is associated with much higher mortality in patients with sepsis. We previously showed that in vitro exposure to moderate hypothermia (32 degrees C) delays the induction and prolongs the duration of TNF-alpha and IL-1beta secretion by lipopolysaccharide (LPS)-stimulated human mononuclear phagocytes. In the present study, we extended these observations by showing that moderate hypothermia exerts effects on TNF-alpha and IL-1beta generation in the human THP-1 monocyte cell line that are similar to those that we previously found in primary cultured monocytes; that hypothermia causes comparable changes in cytokine generation stimulated by zymosan, toxic shock syndrome toxin-1, and LPS; and that hypothermia causes similar changes in TNF-alpha and IL-1beta mRNA accumulation. TNF-alpha mRNA half-life, determined after transcriptional arrest with actinomycin D, was not significantly prolonged by lowering incubation temperature from 37 to 32 degrees C, suggesting that hypothermia modifies TNF-alpha gene transcription. This finding was further supported by reporter gene studies showing a threefold increase in activity of the human TNF-alpha promoter at 32 vs. 37 degrees C. Electrophoretic mobility shift assay revealed that hypothermia prolonged NF-kappaBeta activation, identifying a potential role for this transcription factor in mediating the effects of hypothermia on TNF-alpha and IL-1beta production. Delayed reexpression of the inhibitor IkappaBalpha, shown by Northern blotting and immunoblotting, may account in part for the prolonged NF-kappaBeta activation at 32 degrees C. Augmentation of NF-kappaBeta-dependent gene expression during prolonged exposure to hypothermia may be a common mechanism leading to increased lethality in sepsis, late-onset systemic inflammatory response syndrome after accidental hypothermia, and neuroprotection after ischemia.

Recent evidence strongly implicates the inflammatory response to intrauterine infection in the pathogenesis of neonatal brain and lung injury. We hypothesized that lung and brain injury in preterm infants occurs during a common developmental window of vulnerability as the result of an inflammatory response in different compartments. To determine whether inflammatory markers in these compartments are associated with bronchopulmonary dysplasia (BPD) or cranial ultrasound (CUS) abnormalities in infants <33 wk gestation age (GA) and <1501 g birth weight, we analyzed placental pathology and serum and cerebrospinal fluid (CSF) IL-6, IL-1beta, and tumor necrosis factor-alpha (TNF-alpha) concentrations in 276 infants. Logistic regressions were performed stratified by GA. Histologic chorioamnionitis was significantly associated with BPD in infants /=17 pg/mL was associated with an abnormal CUS in infants >28 wk GA (OR 3.36, p = 0.023) but not /=6.5 pg/mL and TNF-alpha >/=3 pg/mL were associated with abnormal CUS in infants /=28 wk GA. These data suggest that in infants

Febrile-range hyperthermia (FRH) improves survival in experimental infections by accelerating pathogen clearance, but may also increase collateral tissue injury. We hypothesized that FRH would worsen the outcome of inflammation stimulated by a non-replicating agonist and tested this hypothesis in a murine model of pulmonary oxygen toxicity. Using a conscious, temperature-controlled mouse model, we showed that maintaining a core temperature at FRH (39 degrees C to 40 degrees C) rather than at euthermic levels (36.5 degrees C to 37 degrees C) during hyperoxia exposure accelerated lethal pulmonary vascular endothelial injury, reduced the inspired oxygen threshold for lethality, induced expression of granulocyte-colony stimulating factor, and expanded the circulating neutrophil pool. In these same mice, FRH augmented pulmonary expression of the ELR(+) CXC chemokines, KC and LPS-induced CXC chemokine, enhanced recruitment of neutrophils, and changed the histological pattern of lung injury to a neutrophilic interstitial pneumonitis. Immunoblockade of CXC receptor-2 abrogated neutrophil recruitment, reduced pulmonary vascular injury, and delayed death. These combined data demonstrate that FRH may enlist distinct mediators and effector cells to profoundly shift the host response to a defined injurious stimulus, in part by augmenting delivery of neutrophils to sites of inflammation, such as may occur in infections. In certain conditions, such as in the hyperoxic lung, this process may be deleterious.

Ureaplasma urealyticum respiratory tract colonization in preterm infants has been associated with a high incidence of pneumonia and the development of bronchopulmonary dysplasia. However, study of this human pathogen has been hampered by the absence of animal models. We have developed the first juvenile mouse model of Ureaplasma pneumonia and characterized the histopathology during the month following inoculation. C3H/HeN mice were inoculated intratracheally with a mouse-adapted clinical Ureaplasma isolate (biovar 2) or sham inoculated with 10B broth. Culture of lung homogenates and PCR of DNA from bronchoalveolar lavage fluid (BAL) confirmed the presence of Ureaplasma in 100% of inoculated animals at 1 day, 60% at 2 days, 50% at 3 days, and 25% at 7 and 14 days. Ureaplasma was undetectable 28 days postinoculation. There were marked changes in BAL and interstitial-cell composition with increased number of polymorphonuclear leukocytes 1 to 2 days and 14 days postinoculation and macrophages at 2 and 14 days postinoculation. The Ureaplasma infection caused a persistent focal loss of airway ciliated epithelium and a mild increase in interstitial cellularity. There were no differences in BAL protein concentration during the first 28 days, suggesting that pulmonary vascular endothelial barrier integrity remained intact. Comparison of BAL cytokine and chemokine concentrations revealed low levels of tumor necrosis factor alpha (TNF-alpha) at 3 days and monocyte chemoattractant protein 1 at 7 days in Ureaplasma-infected mice but a trend toward increased TNF-alpha at 14 days and increased granulocyte-macrophage colony-stimulating factor and interleukin-10 at 28 days. These data suggest that Ureaplasma alone may cause limited inflammation and minimal tissue injury in the early phase of infection but may promote a mild chronic inflammatory response in the later phase of infection (days 14 to 28), similar to the process that occurs in human newborns.

Context: Placentas are routinely examined by surgical pathologists, but peer review of placental diagnosis is rarely performed., Objective: To determine the frequency of discrepant placental diagnosis between general surgical pathologists and a pediatric pathologist., Design: One hundred fourteen placentas from infants with intrauterine growth restriction (IUGR) and 170 placentas from infants appropriate for gestational age (AGA) were reviewed for 10 lesion types using standardized criteria. The review diagnosis was compared with original reports., Results: The review identified 333 lesions, 168 in the IUGR group and 165 in AGA group. Discrepant diagnosis occurred in 137 lesions (41.1%). There was no significant difference in the frequency of discrepant diagnosis between the IUGR (44.7%) and AGA groups (37.6%) (P >.05). Most discrepancies (92.7%) were due to underdiagnosis (identified on review but not mentioned in original diagnosis), but a few (7.3%) were due to misdiagnosis (mentioned in original report but disagreed on review). The common underdiagnoses with their corresponding rates were as follows: hemorrhagic endovasculitis (84.6%), fetal thrombotic vasculopathy (75%), massive perivillous fibrin deposition (68.4%), maternal floor infarction (66.7%), retroplacental hemorrhage (60.6%), intervillous thrombus (57.1%), decidual angiopathy (33.3%), placental infarction (25.4%), acute chorioamnionitis (22.7%), and chronic villitis (21.7%). Misdiagnosis was found in 10 cases: 5 cases of infarction (review diagnosis was perivillous fibrin deposits in 4, intervillous thrombus in 1), 3 cases of acute chorioamnionitis, and 2 cases of decidual angiopathy. Among the 8 general surgical pathologists involved, the frequency of discrepant diagnosis ranged from 31.5% to 58.6% (P >.05). The intraobserver discrepancy rate for the reviewer was 4.8%, significantly lower than the discrepancy rate for the 8 general surgical pathologists., Conclusion: It is common for general surgical pathologists not to recognize placental lesions, which may have clinical significance. Awareness of this deficiency, standardization of diagnostic criteria, and increased knowledge in placental pathology may improve the quality of diagnosis in this area.

Objective: To evaluate relationships between neonatal intraventricular hemorrhage and altered brain blood flow in preterm growth-restricted fetuses., Methods: One hundred and thirteen growth-restricted fetuses (birth weight < 10th centile and umbilical artery pulsatility index > two standard deviations above gestational age mean) which delivered prematurely (< 34.0 weeks) were studied. Three expressions of altered brain blood flow were defined: 'brain sparing'= middle cerebral artery pulsatility index > two standard deviations below the gestational age mean, 'centralization' = ratio of middle cerebral artery/umbilical artery pulsatility indices (cerebroplacental ratio) > two standard deviations below the gestational age mean, and 'redistribution' = absent or reversed umbilical artery end-diastolic velocity. Intraventricular hemorrhage was graded after Papile (I-IV) by cranial ultrasound performed within 7 days of delivery., Results: Sixty-seven (59.3%) fetuses had brain sparing, 84 (74.3%) had centralization and 51 (45.1%) had redistribution. Fifteen (13.3%) neonates had intraventricular hemorrhage and were more likely to have a biophysical profile < 6, earlier delivery for fetal indications, lower cord artery pH, HCO3, hemoglobin, and platelets, a 10-min Apgar score < 7 and high perinatal mortality (5/15; 33.3%). No associations between intraventricular hemorrhage and brain sparing or centralization were identified. However, neonates with intraventricular hemorrhage had significantly higher umbilical artery pulsatility index deviations from the gestational age mean and a relative risk of 4.9-fold for intraventricular hemorrhage with redistribution (95% confidence interval, 1.5-16.3; P < 0.005). Multiple logistic regression revealed significant associations between intraventricular hemorrhage and a low 10-min Apgar score (r = 0.30, P < 0.005) and low hemoglobin (r = 0.28), gestational age at delivery (r = 0.25) and birth-weight centiles (r = 0.23) (P < 0.05). No Doppler parameter was identified as an independent contributor to intraventricular hemorrhage., Conclusion: While loss of umbilical artery end-diastolic velocity early in gestation significantly increases the risk for neonatal intraventricular hemorrhage, prematurity and difficult transition to extrauterine life remain the most important determinants of intraventricular hemorrhage.