Multicentre randomised trial of invasive and less invasive surfactant delivery methods showed similar spirometry results at 5-9 years of age

AIM

We explored whether subnormal forced expiratory volume within one second (FEV₁ ) at 5-9 years of age was lower in children born preterm who received less invasive surfactant administration (LISA) rather than surfactant via an endotracheal tube.

METHODS

The multicentre, randomised Nonintubated Surfactant Application trial enrolled 211 preterm infants born at 23-26 weeks of gestation from 13 level III neonatal intensive care units from April 2009 to March 2012. They received surfactant via LISA (n=107) or after conventional endotracheal intubation (n=104). The follow-up assessments were carried out by a single team blinded to the group assignments. The main outcome was FEV₁ <80% of predicted values.

RESULTS

Spirometry was successful in 102/121 children. The other children died or were lost to follow up. Median FEV₁ was 93% (interquartile range 80-113%) of predicted values in the LISA group and 86% (interquartile range 77-102%) in the control group (p=0.685). Rates of FEV₁ < 80% were 11/57 (19%) and 15/45 (33 %) respectively, which was an absolute risk reduction of 14% (95% confidence interval -3.1% to 31.2%, p=0.235). There were no differences in other outcome measures.

CONCLUSION

The proportion of children aged 5-9 years with subnormal FEV₁ was not significantly different between the groups.

Gut Dysbiosis With Bacilli Dominance and Accumulation of Fermentation Products Precedes Late-onset Sepsis in Preterm Infants

BACKGROUND

Gut dysbiosis has been suggested as a major risk factor for the development of late-onset sepsis (LOS), a main cause of mortality and morbidity in preterm infants. We aimed to assess specific signatures of the gut microbiome, including metabolic profiles, in preterm infants <34 weeks of gestation preceding LOS.

METHODS

In a single-center cohort, fecal samples from preterm infants were prospectively collected during the period of highest vulnerability for LOS (days 7, 14, and 21 of life). Following 16S rRNA gene profiling, we assessed microbial community function using microbial metabolic network modeling. Data were adjusted for gestational age and use of probiotics.

RESULTS

We studied stool samples from 71 preterm infants with LOS and 164 unaffected controls (no LOS/necrotizing enterocolitis). In most cases, the bacteria isolated in diagnostic blood culture corresponded to the genera in the gut microbiome. LOS cases had a decelerated development of microbial diversity. Before onset of disease, LOS cases had specific gut microbiome signatures with higher abundance of Bacilli (specifically coagulase-negative Staphylococci) and a lack of anaerobic bacteria. In silico modeling of bacterial community metabolism suggested accumulation of the fermentation products ethanol and formic acid in LOS cases before the onset of disease.

CONCLUSIONS

Intestinal dysbiosis preceding LOS is characterized by an accumulation of Bacilli and their fermentation products and a paucity of anaerobic bacteria. Early microbiome and metabolic patterns may become a valuable biomarker to guide individualized prevention strategies of LOS in highly vulnerable populations.

Regulatory T cell frequencies are increased in preterm infants with clinical early-onset sepsis

The predisposition of preterm neonates to invasive infection is, as yet, incompletely understood. Regulatory T cells (Tregs ) are potential candidates for the ontogenetic control of immune activation and tissue damage in preterm infants. It was the aim of our study to characterize lymphocyte subsets and in particular CD4(+) CD25(+) forkhead box protein 3 (FoxP3)(+) Tregs in peripheral blood of well-phenotyped preterm infants (n = 117; 23 + 0 - 36 + 6 weeks of gestational age) in the first 3 days of life in comparison to term infants and adults. We demonstrated a negative correlation of Treg frequencies and gestational age. Tregs were increased in blood samples of preterm infants compared to term infants and adults. Notably, we found an increased Treg frequency in preterm infants with clinical early-onset sepsis while cause of preterm delivery, e.g. chorioamnionitis, did not affect Treg frequencies. Our data suggest that Tregs apparently play an important role in maintaining maternal-fetal tolerance, which turns into an increased sepsis risk after preterm delivery. Functional analyses are needed in order to elucidate whether Tregs have potential as future target for diagnostics and therapeutics.

Increased risk for bronchitis after discharge in non-vaccinated very low birth weight infants

BACKGROUND

In very low birth weight (VLBW) infants, obstructive bronchitis is a frequent cause of hospital re-admission. For VLBW infants, early vaccinations starting at 2 months after birth have been recommended.

OBJECTIVE

To analyze risk factors for bronchitis during the first year after discharge and the effects of in-hospital standard vaccination (hexavalent/pneumococci) and/or RSV immunoprophylaxis with palivizumab.

METHODS

A standardized questionnaire was sent to the parents of VLBW infants 7 month after discharge. The reported episodes of bronchitis were correlated with clinically recorded parameters including risk factors for pulmonary morbidity. The effects of in-hospital vaccination were assessed in a subgroup discharged after day 60.

RESULTS

A sample of 1 967 responses of infants born 2009-2011 was analyzed. Risk factors for bronchitis were male gender and older siblings. 24% of the population had episodes of bronchitis. In the subgroup discharged after day 60, episodes of bronchitis were reported for 31% of infants who were not vaccinated in-hospital. A significant reduction of the bronchitis rate was found in infants who received palivizumab±standard vaccination (17% bronchitis, p=0.003). Interestingly, in-hospital standard vaccination without RSV immunoprophylaxis was protective (20% bronchitis; p=0.037) as well.

CONCLUSIONS

Non-vaccinated male VLBW infants with older siblings are at increased risk for bronchitis during the first year after discharge. Vaccination according to schedule seems to have protective effects, while underlying mechanisms are unknown. The rate of timely vaccination in preterm infants should be increased.

Biophysical activity of animal-derived exogenous surfactants mixed with rifampicin

Exogenous pulmonary surfactant is a potential delivery system for topical medications via the conducting airways. Due to the sensitivity to inactivation of surfactant, mutual interaction with the shipped drug should be evaluated. Little is known about the interactions between surfactant and antimicrobial drugs. The aim of the present study was to evaluate whether biophysical properties of animal-derived surfactants are modified by the bactericidal antibiotic rifampicin. An intracellular activity and a broad antimicrobiotic spectrum toward Gram-negative and Gram-positive bacteria make rifampicin an interesting substance against pulmonary infections. Curosurf® (porcine surfactant from minced lungs) and Survanta® (bovine surfactant extract) were diluted to 2.5-5.0 mg/ml of phospholipids in 0.9 % NaCl and rifampicin (RIF) was added at 1, 5, and 10 % (w/w). Minimum (γ(min)) and maximum (γ(max)) surface tension of a cyclically compressed bubble in the mixture was assessed with a pulsating bubble surfactometer. After 5 min, γ(min) of Survanta at a concentration of 3 mg/ml was significantly increased after addition of 5 and 10 % RIF (both p < 0.001). At 1 % RIF, the γ(min) of Survanta was ≈10 mN/m and this value was not significantly different to that of Survanta alone. The γ(min) of Curosurf at 3 mg/ml was increased with 10 % RIF (p < 0.001), but not with 1 and 5 %. At 5 mg/ml Survanta was inhibited by 10 % RIF (p < 0.05), while γ(min) of Curosurf was low (<5 mN/m) in all mixtures. In conclusion, Curosurf and Survanta interfere with RIF in a concentration-dependent manner. At the appropriate phospholipid concentration, especially porcine-derived surfactant is able to retain good surface activity when mixed with antibiotics.

Pregnancy risk factors for very premature delivery: what role do hypertension, obesity and diabetes play?

PURPOSE

Very premature delivery is a major cause of infant morbidity and mortality. Obesity, diabetes and pregnancy hypertension are known risk factors for pregnancy complications. The study aimed to scrutinize differences of pregnancy complications in a cohort of very premature deliveries compared to a national group.

METHODS

In a multicenter study performed between January 2009 and December 2010 including 1,577 very low birth weight (VLBW) infants, we compared parental reported pregnancy problems of VLBW infants with a national cohort (KIGGS). We compared reported pregnancy complications to reasons for premature delivery and neonatal outcome within the group of VLBW infants.

RESULTS

While parents of the national cohort reported pregnancy-induced hypertension in 8 %, parents of VLBW infants reported this complication more frequently (27 %). Mothers of the national cohort were significantly younger (1 year), suffered less from obesity, anaemia, diabetes. Regression analysis showed that hypertension (OR = 5.11) and advanced maternal age (OR = 1.03) increased the risk for premature birth. Women with hypertension were likely to experience a clinically indicated premature delivery, had more VLBW infants with a moderate growth restriction, but less multiples and their infants had less intraventricular haemorrhages grade 3 or 4. Otherwise, neonatal outcome was correlated with gestational age but not with the pregnancy complications diabetes, hypertension or obesity.

CONCLUSION

Premature birth seems to be correlated to gestational hypertension and associated problems in about ¼ of VLBW infants. Further studies should focus on preventing and treating gestational hypertension to avoid premature delivery and associated neonatal morbidity.

[Bronchopulmonary dysplasia (BPD)]

Alte vs. neue BPD

Die bronchopulmonale Dysplasie (BPD) wurde vor knapp 50 Jahren zunächst als Folgeerkrankung der Beatmungs-/Sauerstofftherapie bei aus heutiger Sicht relativ reifen Frühgeborenen mit schwerem Atemnotsyndrom beschrieben (sog. alte BPD). Der Einsatz von Surfactant und das Überleben immer kleinerer Frühgeborener führten zum Wandel der chronischen Lungenerkrankung. Die sog. neue BPD ist eine unreifeassoziierte Multisystemerkrankung, die durch einen Stopp bzw. eine Verzögerung/Vereinfachung der Lungenentwicklung in einer sehr frühen Phase charakterisiert ist.

Therapie

Bis heute kommt bei BPD eine überwiegend symptomatische Therapie zum Einsatz. Wachstumsfaktoren und auch Stammzellen wurden in Tierversuchen erfolgreich eingesetzt.

Outcome

Langzeitauswirkungen der BPD sind in Bezug auf die Lungenfunktion, das Wachstum, das Herz-Kreislauf-System sowie die statomotorische und kognitive Entwicklung bis in das Erwachsenenalter hinein zu erwarten.

Major Contributors to Hospital Mortality in Very-Low-Birth-Weight Infants: Data of the Birth Year 2010 Cohort of the German Neonatal Network

The German Neonatal Network (GNN) is a prospective cohort study with the focus on long term development of very-low-birth-weight infants. It was the aim of this study to determine detailed information on causes of mortality in the GNN birth cohort 2010.

Major contributors to hospital mortality were recorded by the attending neonatologists for the cohort of very-low-birth-weight (VLBW) infants born in centres of the German Neonatal Network (GNN) in 2010. The data quality was approved by on-site monitoring.

2 221 VLBW infants were born in GNN centres in 2010, and death occurred in 221 infants. Male infants carried a higher risk than females (58.8% males among non-survivors vs. 51.7% among survivors, p=0.047). In 11 infants, the major contributor to death was not determined by the attending neonatologist. In 25 infants born at the limit of viability, comfort palliative care was primarily initiated and 14 infants had lethal malformations. The majority of non-survivors suffered from inflammatory diseases including sepsis- or necrotizing enterocolitis (NEC)-associated death (n=56). Respiratory pathology was a major contributor to death in 65 infants including 11 infants who died from pulmonary haemorrhage.

Potentially preventable complications of preterm birth such as sepsis, NEC and pulmonary haemorrhage predominate the major contributors to mortality in the GNN 2010 cohort. In order to decrease the rate of these associated deaths, future trials should focus on prophylaxis and therapy optimization strategies for these outcomes.

Galectin-3 in cord blood of term and preterm infants

In recent years galectin-3 has gained attention as a signalling molecule, mainly in inflammatory diseases. Data on galectin-3 expression in neonates, however, are limited, and expression of this lectin in cord blood has not yet been reported. The aim of this study was to determine galectin-3 levels in cord blood of term and preterm neonates as well as galectin-3 levels in cord blood of term neonates after stimulation with the prevalent pathogen Streptococcus agalactiae. Cord blood samples were incubated for 24 h and galectin-3 levels were assessed by enzyme-linked immunosorbent assay. There is a positive correlation between gestational age and galectin-3 levels in cord blood. Expression of galectin-3 is significantly higher in cord blood of small-for-gestational-age infants compared to appropriate-for-gestational-age infants. Stimulation with an invasive but not with a colonizing strain of S. agalactiae induced expression of galectin-3. Galectin-3 is expressed constitutively in cord blood of neonates and seems to play a role in the innate immunity of this population.

Surfactant without intubation in preterm infants with respiratory distress: first multi-center data

BACKGROUND

Recently in a report of a single center a method has been described to apply surfactant via a thin endotracheal catheter to very low birth weight infants spontaneously breathing with nasal continuous positive airway pressure. We now analyzed available multicenter data.

PATIENTS AND METHODS

In a multicenter study investigating genetic risk factors, clinical and outcome data and data of antenatal and postnatal treatment of infants with a birth weight below 1,500 g were prospectively recorded. The measures of infants treated with the new method of surfactant application were compared to those of infants who received standard care. The analysis was restricted to infants with a gestational age below 31 weeks (n=1,541).

RESULTS

319 infants were treated with the new method and 1,222 with standard care. The need for mechanical ventilation during the first 72 h (29% vs. 53%, p<0.001), the rate of bronchopulmonary dysplasia defined as oxygen at 36 weeks of postmenstrual age (10.9 % vs. 17.5%, p=0.004) and the rate of death or bronchopulmonary dysplasia were significantly lower in the treatment group than in the standard care group. Surfactant, theophyllin, caffeine and doxapram were significantly more often and analgetics, catecholamines and dexamethasone were significantly less frequently used in the treatment group.

CONCLUSIONS

A new method of surfactant application was associated with a lower prevalence of mechanical ventilation and better pulmonary outcome. A prospective controlled trial is required to determine whether this approach is superior to standard care.

Polymorphisms in the Renin-Angiotensin system and outcome of very-low-birthweight infants

BACKGROUND

The insertion/deletion polymorphism of the angiotensin-converting enzyme (ACE-ins/del) and the angiotensin II type 1 receptor 1166A/C polymorphism (ATR1166A/C) were reported to be associated with several unfavorable outcome parameters in preterm infants like bronchopulmonary dysplasia, persistent ductus arteriosus and impaired insulin sensitivity.

OBJECTIVE

To confirm the above-mentioned associations in a large cohort of very-low-birthweight (VLBW) infants.

METHOD

Clinical data of VLBW infants were prospectively recorded. The ACE-ins/del polymorphism and the ATR1166A/C polymorphism were determined by polymerase chain reaction in 1,209 and 1,168 infants, respectively.

RESULTS

There was no significant association between ACE-ins/del or ATR1166A/C genotype and outcome parameters (death, intraventricular hemorrhage, sepsis, bronchopulmonary dysplasia, ventilation, supplemental oxygen at discharge, postnatal treatment with insulin, surgery for intestinal perforation/necrotizing enterocolitis/retinopathy of prematurity/persistent ductus arteriosus.

CONCLUSION

Both known functional polymorphisms of the renin-angiotensin system do not seem to be associated with the outcome of VLBW infants.

Outcome of extremely premature infants at early school age: health-related quality of life and neurosensory, cognitive, and behavioral outcomes in a population-based sample in northern Germany

PURPOSE

The study aimed at collecting regional data to support and establish evidence-based decision-making.

METHODS

We investigated a cohort of 154 preterm infants with gestational age <27+0 weeks born between 1997 and 1999 in a defined region of Northern Germany regarding neurosensory and cognitive outcomes, overall disability status, behavioral problems, and health-related quality of life at the age of seven to nine years (mean: eight years, SD seven months).

RESULTS

92 (60%) infants survived, 75 of these 92 (82%) were followed-up. Rates of disability were high: only 27 (36%) showed 'no dysfunction' of neurosensory status, 33 (44%) 'mild dysfunction', 5 (7%) 'moderate dysfunction' and 10 (13%) 'severe dysfunction', including 8 (11%) with non-ambulatory cerebral palsy. 19 (26%) were mentally retarded. Parents reported behavioral problems in 21 (28%), health-related quality of life was lower in preterm infants compared to a representative normal sample. In multivariate analyses IVH III-IV/PVL was an independent risk factor for adverse outcomes. Behavior problems were predicted by low IQ and lower educational level of the mother.

CONCLUSIONS

Overall our results confirm high levels of mortality and morbidity in extremely immature infants. Regional data should include mortality, morbidity and health-related quality of life to adequately inform parents about the prognosis.

[Asthma in children - is it different?]

Asthma is the most commonly observed chronic disease in childhood and the incidence has been increasing in industrialized countries over the last decades. Airway obstruction due to increased sensitivity of the small airways, mucus production and chronic inflammation are key features in the pathophysiology of asthma. Environmental and genetic factors predispose for the disease, which is clinically characterized by sudden occurrence of episodes of expiratory airway obstruction (wheezing). In the majority of preschool infants such obstructive episodes are triggered by viral infections (especially during the winter season) and do not necessarily predispose for asthma later in adulthood. Patient and family history (e.g. atopy), good clinical examination and differential diagnosis (e.g. exclusion of cystic fibrosis) are of prime importance as the role of lung function measurements is limited as the disease frequently occurs before the age of 5 years. Information about asthma is important for children, parents and caregivers. Acute and chronic medication should control asthma symptoms and allow the affected child to lead a normal life including physical exercise.

Characterisation of the host inflammatory response to Staphylococcus epidermidis in neonatal whole blood

BACKGROUND

Coagulase-negative staphylococci (CoNS) are the most prevalent pathogens causing late-onset sepsis, and gestational age is the most important risk factor for these infections.

OBJECTIVE

To characterise innate immune responses to S epidermidis by assessment of whole blood in vitro cytokine production in a large group of preterm and term infants.

RESULTS

The S epidermidis-induced in vitro production of proinflammatory cytokines such as intracytoplasmic interleukin (IL) 6 and tumour necrosis factor alpha in cord blood samples was found to be dependent on gestational age (R = 0.279, 95% CI 0.10 to 0.44, p = 0.002; R = 0.251, 95% CI 0.07 to 0.41, p = 0.005, respectively; n = 121). In contrast, the production of anti-inflammatory cytokines such as IL10 and transforming growth factor beta was not associated with gestational age. When different stimulation strategies were compared, a strong correlation was noted for cytokine responses after lipopolysaccharide and S epidermidis exposure--that is, IL6 (R = 0.431, 95% CI 0.29 to 0.55, p<0.001, n = 161) and IL10 (R = 0.332, 95% CI 0.18 to 0.47, p<0.001, n = 161). In addition, a lower IL6 production was found in supernatants of whole blood cultures infected with a clinically isolated IcaABD-positive (biofilm production) strain compared with a control IcaABD-negative ATCC strain (p = 0.009).

CONCLUSIONS

These in vitro data suggest that proinflammatory responses to S epidermidis are dependent on gestational age in preterm infants, whereas the counteracting anti-inflammatory response to S epidermidis may not be directly related to gestational age. Individual host factors may have a role as well as bacterial determinants, such as biofilm production. Further studies are encouraged to investigate the different aspects of innate immune responses to CoNS in vivo.