Christoph Härtel

Avoidance of mechanical ventilation by surfactant treatment of spontaneously breathing preterm infants (AMV): an open-label, randomised, controlled trial.

BACKGROUND Surfactant is usually given to mechanically ventilated preterm infants via an endotracheal tube to treat respiratory distress syndrome. We tested a new method of surfactant application to spontaneously breathing preterm infants to avoid mechanical ventilation. METHOD In a parallel-group, randomised controlled trial, 220 preterm infants with a gestational age between 26 and 28 weeks and a birthweight less than 1·5 kg were enrolled in 12 German neonatal intensive care units. Infants were independently randomised in a 1:1 ratio with variable block sizes, to standard treatment or intervention, and randomisation was stratified according to centre and multiple birth status. Masking was not possible. Infants were stabilised with continuous positive airway pressure and received rescue intubation if necessary. In the intervention group, infants received surfactant treatment during spontaneous breathing via a thin catheter inserted into the trachea by laryngoscopy if they needed a fraction of inspired oxygen more than 0·30. The primary endpoint was need for any mechanical ventilation, or being not ventilated but having a partial pressure of carbon dioxide more than 65 mm Hg (8·6 kPa) or a fraction of inspired oxygen more than 0·60, or both, for more than 2 h between 25 h and 72 h of age. Analysis was by intention to treat. This study is registered, number ISRCTN05025922. FINDINGS 108 infants were assigned to the intervention group and 112 infants to the standard treatment group. All infants were analysed. On day 2 or 3 after birth, 30 (28%) infants in the intervention group were mechanically ventilated versus 51 (46%) in the standard treatment group (number needed to treat 6, 95% CI 3-20, absolute risk reduction 0·18, 95% CI 0·30-0·05, p=0·008). 36 (33%) infants in the intervention group were mechanically ventilated during their stay in the hospital compared with 82 (73%) in the standard treatment group (number needed to treat: 3, 95% CI 2-4, p<0·0001). The intervention group had significantly fewer median days on mechanical ventilation, (0 days. IQR 0-3 vs 2 days, 0-5) and a lower need for oxygen therapy at 28 days (30 infants [30%] vs 49 infants [45%], p=0·032) compared with the standard treatment group. We recorded no differences between groups for mortality (seven deaths in the intervention group vs five in the standard treatment group) and serious adverse events (21 vs 28). INTERPRETATION The application of surfactant via a thin catheter to spontaneously breathing preterm infants receiving continuous positive airway pressure reduces the need for mechanical ventilation. FUNDING German Ministry of Research and Technology, University of Lübeck, and Chiesi Pharmaceuticals.

Cytokine responses correlate differentially with age in infancy and early childhood

The functional differentiation of immune cells at early age plays a central role in immune physiology, e.g. for the sufficient eradication of pathogens. However, imbalances in effector cell responses may also have an impact in the pathophysiology of childhood diseases such as atopy and autoimmune disorders. As information on immune cell responses in infancy and early childhood is scarce, we conducted an observational, cross‐sectional study in healthy newborns (n = 18), infants and young children (n = 54) aged 1–96 months and adult controls (n = 19) to assess cytokine mRNA and protein expression upon phorbol 12‐myristate 13‐actate/ionomycin stimulation and LPS‐induced IL‐12 expression in monocytes. The intracellular expression of interferon (IFN)‐γ, tumour necrosis factor (TNF)‐α (R = 0·748, P < 0·0001; R = 0·784, P < 0·0001, respectively) and interleukin (IL)‐2 protein expression (R = 0·384, P = 0·008) was demonstrated to increase progressively with age. While a correlation between IL‐4 protein expression and age was noted (R = 0·342, P = 0·007), the levels of IL‐5 and IL‐10 protein expression tended to be regulated on an individual basis during infancy and early childhood. An age correlation was also observed for intracellular IL‐12 expression (R = 0·331, P = 0·009) in monocytes. These findings are valuable for further assessment of normal variations and maturation processes in immune cell responses and for the clinical–therapeutic monitoring of immunological status in various childhood diseases.

Immature anti-inflammatory response in neonates

The inflammatory response plays a major role in the induction of several neonatal diseases. We hypothesize that an imbalance between the pro‐ and anti‐inflammatory response is crucial for the previously shown enhanced production of proinflammatory cytokines in term and preterm infants during infection. To test this hypothesis, we compared the capacity to produce the main anti‐inflammatory cytokines IL‐10 and TGF‐β in term infants, preterm infants and adults at different levels of synthesis by quantitative real time reverse‐transcribed PCR, flow cytometry, as well as enzyme‐linked immunoassay. Term and preterm infants showed a profoundly diminished IL‐10 mRNA‐expression and IL‐10 production after stimulation. In addition, the amount of TGF‐β‐positive lymphocytes was significantly less in neonates than adults. Furthermore, there was a considerably lower inhibition of production of IL‐1α, IL‐6, IL‐8 and TNF‐α by the use of recombinant IL‐10 in term and preterm infants compared with adults. These results demonstrate not only a diminished anti‐inflammatory capacity but also a reduced response to anti‐inflammatory stimuli in term and preterm infants. From these data we conclude that neonates display an immature compensatory anti‐inflammatory response syndrome (CARS) which may predispose preterm infants to harmful effects of proinflammatory cytokines resulting in severe organ sequelae during infection.

Ex vivo induction of cytokine mRNA expression in human blood samples.

The interest in the quantitative analysis of cytokine mRNA profiles has increased substantially in recent years. This is based on the potential use of basal cytokine mRNA expression as sensitive markers for in vivo lymphocyte activation in a variety of clinical settings. However, it is less well known to what extent differences in blood collection and preparation techniques may cause ex vivo alteration of quantitative cytokine mRNA levels. We therefore evaluated the effect of blood sampling and the impact of cell separation on interleukin (IL)-2, IL-4, interferon (IFN)-gamma and tumour necrosis factor (TNF)-alpha mRNA expression in an intraindividual study design (n=8). Two different blood sampling procedures were applied. A whole blood sample 1 was collected by constant moderate blood flow into a blood collection tube containing lithium-heparin. Moreover, a second sample from the same donor was collected by a 5-fold acceleration of blood flow. Furthermore, peripheral blood mononuclear cell (PBMC) were isolated from the first whole blood sample by density separation over Ficoll-Hypaque. The quantification of cytokine mRNA expression was performed by real-time PCR in native whole blood/PBMC samples or unstimulated cultures. We found a significant increase of IL-2, IL-4 and TNF-alpha mRNA expression (P=0.018, P=0.028, P=0.018) in whole blood samples collected by rapid sampling. The isolation of PBMC by density gradient separation prompted on upregulation of the mRNA levels of IL-2, IL-4 and TNF-alpha 5-9-fold (P=0.018, P=0.018, P=0.018). In contrast, IFN-gamma mRNA expression was not significantly influenced by differences in blood sample preparation. Our data clearly demonstrate that differences in the blood sampling technique or cell separation should be considered as important factors for non-physiological ex vivo induction of cytokine mRNA expression. The current data emphasize the need for data on the impact of ex vivo variation in order to extract reliable and consistent information, particularly when cytokine mRNA expression data from healthy blood donors are included in clinical studies.

Association Between Azithromycin Therapy and Duration of Bacterial Shedding Among Patients With Shiga Toxin–Producing Enteroaggregative Escherichia coli O104:H4

CONTEXT An outbreak of Shiga toxin-producing enteroaggregative Escherichia coli (STEC O104:H4) infection with a high incidence of hemolytic uremic syndrome (HUS) occurred in Germany in May 2011. Antibiotic treatment of STEC infection is discouraged because it might increase the risk of HUS development. However, antibiotic therapy is widely used to treat enteroaggregative E coli infection. In the German outbreak, a substantial number of patients received prophylactic azithromycin treatment as part of a therapeutic regimen with the C5 antibody eculizumab. OBJECTIVE To analyze the duration of bacterial shedding in patients with STEC infection who did and did not receive oral azithromycin therapy. DESIGN, SETTING, AND PATIENTS At a single center in Lübeck, Germany, 65 patients with STEC infection, including patients with HUS as well as STEC-infected outpatients without manifestation of HUS, were investigated between May 15 and July 26, 2011, and were monitored for a mean of 39.3 days after onset of clinical symptoms. MAIN OUTCOME MEASURE Carriage of STEC after azithromycin therapy. RESULTS Twenty-two patients received oral azithromycin and 43 patients did not receive antibiotic treatment. Among antibiotic-treated patients, long-term STEC carriage (>28 days) was observed in 1 of 22 patients (4.5%; 95% CI, 0%-13.3%) compared with 35 of 43 patients (81.4%; 95% CI, 69.8%-93.0%) who were not treated with antibiotics (P < .001). All 22 patients receiving azithromycin treatment had at least 3 STEC-negative stool specimens after the completion of treatment, and no recurrence of STEC was observed in these patients. As proof of principle, 15 patients who initially were not treated with antibiotics and were long-term STEC carriers were treated with oral azithromycin given for 3 days and subsequently had negative stool specimens. CONCLUSION Treatment with azithromycin was associated with a lower frequency of long-term STEC O104:H4 carriage.

Mutations of Genes Involved in the Innate Immune System as Predictors of Sepsis in Very Low Birth Weight Infants

Mutations of genes involved in the innate immune system have been reported to be associated with an increased sepsis rate in adults. We determined the −159T mutation of the CD14 gene, the 896G mutation of the toll-like receptor 4 gene, the 3020insC mutation of the NOD2 gene (NOD2-3020insC), the IL-6 174G/C promoter polymorphism (IL6-174G/C), and the mannose-binding lectin genotype and their association to the subsequent development of neonatal sepsis in a large cohort of very low birth weight (VLBW) infants. Fifty (14%) of 356 VLBW infants developed blood culture–proven sepsis during their stay in the hospital. VLBW infants carrying the NOD2-3020insC allele (n =15) and the IL6-174G allele (n =121) had a significantly higher rate of blood culture–proven sepsis (33% and 19.8%, respectively) than VLBW infants without these genotypes (p = 0.046 and 0.035, respectively). In a multivariate logistic regression analysis, gestational age less than 28 wk (odds ratio, 3.2; 95% confidence interval, 1.7–6.0; p < 0.001) and the homozygous IL6-174G allele (odds ratio, 1.9; 95% confidence interval, 1.0–3.9; p = 0.039) were predictive for the development of sepsis, whereas the NOD2-3020insC allele was only of borderline significance (odds ratio, 3.2; 95% confidence interval, 1.0–10.4; p = 0.052). VLBW infants with repeated episodes of sepsis had higher frequencies of the NOD2-3020insC and IL6-174G allele. The increased sepsis rate of homozygous IL6-174G carriers was especially related to an increase in Gram-positive infections, and was not observed in VLBW infants who received prophylaxis with teicoplanin (frequency of Gram-positive sepsis in homozygous IL6-174G carriers without prophylaxis 16.5%versus 2.4% in homozygous IL6-174G carriers with prophylaxis; p = 0.033).

An Outbreak of Shiga Toxin–Producing Escherichia coli O104:H4 Hemolytic Uremic Syndrome in Germany: Presentation and Short-term Outcome in Children

BACKGROUND In May and June 2011 the largest known outbreak of hemolytic uremic syndrome (HUS) occurred in northern Germany. Because, quite unusually, a large number of adults was affected and the causative Escherichia coli strain, serotype O104:H4, showed an atypical virulence factor pattern, it was speculated that this outbreak was associated with an aggressive course and an unfavorable prognosis also in children. METHODS Retrospective analysis of medical records of 90 children and comparison to previous outbreak and sporadic case series. RESULTS Median age was unusually high (11.5 years) compared with that in historical series. Only 1 patient (1.1%) died in the acute phase. Most patients (67/90 [74%]) received supportive care only. Renal replacement therapy was required in 64 of 90 (71%) of the children. Neurological complications, mainly seizures and altered mental stage, were present in 23 of 90 (26%) patients. Ten patients received plasmapheresis, 6 eculizumab, and 7 a combination of both. After a median follow-up of 4 months, renal function normalized in 85 of 90 (94%) patients, whereas 3 patients had chronic kidney disease stage 3 or 4, and 1 patient (1.1%) still requires dialysis. Complete neurological recovery occurred in 18 of 23 patients. Mild to moderate and major residual neurological changes were present in 3 patients and 1 patient, respectively, although all patients were still improving. CONCLUSIONS E. coli O104:H4 caused the largest HUS outbreak in children reported in detail to date and most patients received supportive treatment only. Initial morbidity, as well as short-term outcome, due to this pathogen, is comparable to previous pediatric series of Shiga toxin-producing E. coli HUS.

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.

Levetiracetam in children with refractory epilepsy: A multicenter open label study in Germany

PURPOSE To evaluate the efficacy and tolerability of Levetiracetam (LEV) in a large pediatric cohort with drug-resistant epilepsy from a prospective multicenter observational study. METHODS We report the results of a multicenter observational survey of a cohort of 285 pediatric patients (mean: 9.9 years, range: 0; 6-17; 11) with refractory generalized and focal epilepsy who received Levetiracetam as an add-on open label treatment trial. The average duration of epilepsy was 6.0 years and the patients were treated with a mean of 7.0 antiepileptic drugs (AED) before LEV was introduced. RESULTS No serious persistent adverse events were reported. Reversible colitis and an apnoea syndrome in a child with phosphorylase-A-kinase-deficiency were noted. Mild to moderate side effects were reported in 128 patients (44.9%), consisting most frequently of somnolence (23.9%), general behavioral changes (15.4%), aggression (10.5%) and sleep disturbances (3.2%). In 209 patients, efficacy was analyzed over a treatment period of at least 12 weeks compared to a baseline of 2 weeks. Thirteen patients (6.2%) became seizure free, 39 (18.7%) responded with a seizure reduction of more than 50% following introduction of LEV. No response to LEV was reported in 65.1% (n=136). A decrease of initial treatment effect was seen in 37 patients (17.8%) while in 6.7% the seizure frequency doubled to the baseline (n=14). In seven patients (3.3%), the effect of LEV on seizure frequency could not be evaluated. A positive psychotropic effect was observed in 18 patients (8.6%). Mental retardation was associated with poor response and associated with more side effects and earlier discontinuation of LEV therapy. CONCLUSION LEV is a well-tolerated new AED that may effectively improve seizure control as an add-on drug in resistant epilepsy in childhood with good tolerability. However, neurologically handicapped children appear at increased risk for reversible neurocognitive side effects and have a poorer treatment response.

Genetic Polymorphisms of Hemostasis Genes and Primary Outcome of Very Low Birth Weight Infants

BACKGROUND. Recent investigations have reported an influence of thrombophilic mutations and antithrombotic risk factors with development of intraventricular hemorrhage. It was our objective for this study to investigate the impact of genetic polymorphisms of hemostasis genes on the primary outcome measures of sepsis, bronchopulmonary dysplasia, intraventricular hemorrhage, and periventricular leukomalacia in a large cohort of very low birth weight infants. METHODS. There were 586 very low birth weight infants enrolled prospectively in a multicenter trial between September 2003 and July 2005, and an additional 595 very low birth weight infants, who had been recruited in a previous prospective trial, were studied. DNA samples were taken by buccal swab, and genotypes of factor V Leiden mutation, prothrombin G20210A mutation, the factor VII-323 del/ins polymorphism, and the factor XIII-Val34Leu polymorphisms were determined by polymerase chain reaction and restriction enzyme digestion. RESULTS. In contrast to data published previously, the frequency of intraventricular hemorrhage or periventricular leukomalacia was not significantly influenced by any of the genetic variants tested. Carriers of the factor XIII-Val34Leu polymorphism, however, had a higher sepsis rate and a longer period of hospital care compared with noncarriers. The factor VII-323 del/ins polymorphism was found to be a potential protective factor against bronchopulmonary dysplasia. CONCLUSIONS. We could not confirm previously reported associations of hemostasis gene variants and development of intraventricular hemorrhage in very low birth weight infants. To better understand gene-disease associations in very low birth weight infants, the prospective development of large-scale cohorts with well-defined phenotypes and corresponding DNA samples is essential.