Epidemic Microclusters of Blood-Culture Proven Sepsis in Very-Low-Birth Weight Infants: Experience of the German Neonatal Network

INTRODUCTION: We evaluated blood culture-proven sepsis episodes occurring in microclusters in very-low-birth-weight infants born in the German Neonatal Network (GNN) during 2009-2010. METHODS: Thirty-seven centers participated in GNN; 23 centers enrolled ≥50 VLBW infants in the study period. Data quality was approved by on-site monitoring. Microclusters of sepsis were defined as occurrence of at least two blood-culture proven sepsis events in different patients of one center within 3 months with the same bacterial species. For microcluster analysis, we selected sepsis episodes with typically cross-transmitted bacteria of high clinical significance including gram-negative rods and Enterococcus spp. RESULTS: In our cohort, 12/2110 (0.6%) infants were documented with an early-onset sepsis and 235 late-onset sepsis episodes (≥72 h of age) occurred in 203/2110 (9.6%) VLBW infants. In 182/235 (77.4%) late-onset sepsis episodes gram-positive bacteria were documented, while coagulase negative staphylococci were found to be the most predominant pathogens (48.5%, 95%CI: 42.01-55.01). Candida spp. and gram-negative bacilli caused 10/235 (4.3%, 95%CI: 1.68% -6.83%) and 43/235 (18.5%) late-onset sepsis episodes, respectively. Eleven microclusters of blood-culture proven sepsis were detected in 7 hospitals involving a total 26 infants. 16/26 cluster patients suffered from Klebsiella spp. sepsis. The median time interval between the first patient's Klebsiella spp. sepsis and cluster cases was 14.1 days (interquartile range: 1-27 days). First patients in the cluster, their linked cases and sporadic sepsis events did not show significant differences in short term outcome parameters. DISCUSSION: Microclusters of infection are an important phenomenon for late-onset sepsis. Most gram-negative cluster infections occur within 30 days after the first patient was diagnosed and Klebsiella spp. play a major role. It is essential to monitor epidemic microclusters of sepsis in surveillance networks to adapt clinical practice, inform policy and further improve quality of care

Difficidin and bacilysin produced by plant-associated Bacillus amyloliquefaciens are efficient in controlling fire blight disease

Representatives of Bacillus amyloliquefaciens were shown to possess biocontrol activity against fire blight, a serious disease of orchard trees caused by Erwinia amylovora. Genome analysis of B. amyloliquefaciens FZB42 identified gene clusters responsible for synthesis of several polyketide compounds with antibacterial action.We show here that the antibacterial polyketides difficidin and to a minor extent bacillaene act efficiently against E. amylovora. Surprisingly, a mutant strain blocked in the production of difficidin (CH8 Δdfn) inhibited growth of E. amylovora and suppressed fire blight disease nearly in the same range as the wild type. In addition, a sfp mutant (CH3Δsfp) unable to synthesize non-ribosomally lipopeptides and polyketides did still suppress growth of E. amylovora, suggesting that besides action of polyketidesanother antagonistic principle exist. Adouble mutant (RS06ΔsfpΔbac) devoid in polyketide and bacilysin synthesis was unable to suppress growth of E. amylovora indicating that the additional inhibitory effect is due to production of bacilysin, a dipeptide whose synthesis does not depend on Sfp. We propose to use B. amyloliquefaciens strains with enhanced synthesis of difficidin and/or bacilysin for development of biocontrol agents efficient against fire blight disease

Active perinatal care of preterm infants in the German Neonatal Network

Objective To determine if survival rates of preterm infants receiving active perinatal care improve over time. Design The German Neonatal Network is a cohort study of preterm infants with birth weight P75), intermediate (P25-P75) and low (<P25) survival. We compared these survival rates with data in 2014-2016. Main outcome measures Death by any cause before discharge. Results Total survival increased from 85.8% in 2011-2013 to 87.4% in 2014-2016. This increase was due to reduced mortality of NICUs with low survival rates in 2011-2013. Survival increased in these centres from 53% to 64% in the 22-24 weeks strata and from 73% to 84% in the 25-26 weeks strata. Conclusions Our data support previous reports that active perinatal care of very immature infants improves outcomes at the border of viability and survival rates at higher gestational ages. The high total number of surviving infants below 24 weeks of gestation challenges national recommendations exclusively referring to gestational age as the single criterion for providing active care. However, more data are needed before recommendations for parental counselling should be reconsidered

Pathogenic spectrum of blood-culture proven sepsis episodes.

*<p>Estimate: estimated risk for specific pathogen/100 cases of blood-culture proven sepsis.</p

Outcome of patients in microclusters of blood-culture proven sepsis.

<p><b>Legend:</b> IVH intraventricular haemorrhage; Surgery for PDA Patent Ductus arteriosus, NEC necrotizing enterocolitis, FIP focal intestinal perforation, ROP retinopathy of prematurity (kryo- or laser therapy); BPD bronchopulmonary dysplasia; severe complication: IVH grade IV, posthaemorrhagic hydrocephalus with need for VP shunt, periventricular leukomalacia, surgery for NEC/FIP or ROP and BPD;</p><p>p-values were derived from chi-square test if not otherwise indicated (* Mann-Whitney-U test comparing linked cases vs. first patient in cluster.</p

Clinical characteristics of the VLBW cohort stratified to occurrence of late-onset sepsis (LOS).

<p><b>Legend:</b> PPROM Preterm premature rupture of membranes, C/section Caesarean section, SGA small-for-gestational-age (<10th Voigt percentile).</p><p># p-values were derived from chi-square test if not otherwise indicated (* Mann-Whitney-U test).</p