Insights into B-cell ontogeny inferred from human immunology.

Due to ontogenetic changes in B-cell developmental lineages, the mature B-cell compartment constitutes by functionally different B-cell subsets that emerged from prenatal, early postnatal or adult precursors. While negative selection processes operate primarily within the framework of B-cell tolerance checkpoints during B-cell development, further differentiation into distinct B-cell subsets is additionally induced by positive selection. In addition to endogenous antigens, contact with microbial antigens is also involved in this selection process, with intestinal commensals having a significant influence on the development of a large layer within the B-cell compartment. The decisive threshold that triggers negative selection seems to be relaxed during fetal B-cell development, thereby allowing recruitment of polyreactive and also autoreactive B-cell clones into the mature naïve B-cell compartment. Almost all of the concepts on B-cell ontogeny are based on observations in laboratory mice that not only differ from humans in their developmental timeline but also in their composition of commensal microorganisms or rather a lack of exposure to these. In this review, we summarize conceptual findings on B-cell ontogeny and particularly describe key insights into the developing human B-cell compartment and immunoglobulin repertoire formation.

Estimates of protection levels against SARS-CoV-2 infection and severe COVID-19 in Germany before the 2022/2023 winter season: the IMMUNEBRIDGE project.

PURPOSE: Despite the need to generate valid and reliable estimates of protection levels against SARS-CoV-2 infection and severe course of COVID-19 for the German population in summer 2022, there was a lack of systematically collected population-based data allowing for the assessment of the protection level in real time. METHODS: In the IMMUNEBRIDGE project, we harmonised data and biosamples for nine population-/hospital-based studies (total number of participants n = 33,637) to provide estimates for protection levels against SARS-CoV-2 infection and severe COVID-19 between June and November 2022. Based on evidence synthesis, we formed a combined endpoint of protection levels based on the number of self-reported infections/vaccinations in combination with nucleocapsid/spike antibody responses ("confirmed exposures"). Four confirmed exposures represented the highest protection level, and no exposure represented the lowest. RESULTS: Most participants were seropositive against the spike antigen; 37% of the participants ≥ 79 years had less than four confirmed exposures (highest level of protection) and 5% less than three. In the subgroup of participants with comorbidities, 46-56% had less than four confirmed exposures. We found major heterogeneity across federal states, with 4-28% of participants having less than three confirmed exposures. CONCLUSION: Using serological analyses, literature synthesis and infection dynamics during the survey period, we observed moderate to high levels of protection against severe COVID-19, whereas the protection against SARS-CoV-2 infection was low across all age groups. We found relevant protection gaps in the oldest age group and amongst individuals with comorbidities, indicating a need for additional protective measures in these groups.

Antimicrobial Peptides (AMPs) and the Microbiome in Preterm Infants: Consequences and Opportunities for Future Therapeutics.

Antimicrobial peptides (AMPs) are crucial components of the innate immune system in various organisms, including humans. Beyond their direct antimicrobial effects, AMPs play essential roles in various physiological processes. They induce angiogenesis, promote wound healing, modulate immune responses, and serve as chemoattractants for immune cells. AMPs regulate the microbiome and combat microbial infections on the skin, lungs, and gastrointestinal tract. Produced in response to microbial signals, AMPs help maintain a balanced microbial community and provide a first line of defense against infection. In preterm infants, alterations in microbiome composition have been linked to various health outcomes, including sepsis, necrotizing enterocolitis, atopic dermatitis, and respiratory infections. Dysbiosis, or an imbalance in the microbiome, can alter AMP profiles and potentially lead to inflammation-mediated diseases such as chronic lung disease and obesity. In the following review, we summarize what is known about the vital role of AMPs as multifunctional peptides in protecting newborn infants against infections and modulating the microbiome and immune response. Understanding their roles in preterm infants and high-risk populations offers the potential for innovative approaches to disease prevention and treatment.

[The Duplicity of Incidents: Cervical Lymphatic Malformation in two Newborns]. / Die Duplizität der Ereignisse: Zervikale lymphatische Malformation bei zwei Neugeborenen.

We report on two neonates born the same day, both with an isolated cervical lymphatic malformation. Cervical masses were detected by ultrasound late in the third trimester. Following interdisciplinary case conferences, a caesarean section in the presence of a neonatal team was the chosen delivery mode in both cases. Delivery and transition of the newborns were uneventful. The suspected diagnosis was confirmed by postnatal MRIs, which demonstrated neither associated malformations nor compression of vital structures. Therefore, an expectant approach was chosen for the newborn with the smaller lesion. The other newborn featured a sizeable lymphatic malformation, and due to consecutive head tilt, sclerotherapy was initiated in its second week of life. Our case report outlines the challenges of a rare connatal malformation. Guidelines are often missing. Individual decisions regarding delivery mode, diagnostics and therapy have to be made on an interdisciplinary basis and patients as well as parents need counseling and support over a long period. All the more significant is good, interdisciplinary collaboration between the involved disciplines.

Use and Impact of Pessary, Cerclage, and Progesterone for the Secondary Prevention of Preterm Birth: Data from the German Neonatal Network.

BACKGROUND: To evaluate the use and effect of cervical stitch cerclage, pessary, and progesterone on pregnancy outcome in mothers of very low birth weight infants (VLBWI) born<32 weeks of gestation in the German Neonatal Network (GNN). METHODS: The GNN is a population-based cohort study enrolling VLBWI since 2009. We included 575 neonates from 424 mothers into our analysis, who were born between 2015 and 2019, after prenatal intervention with cerclage, pessary, progesterone or a combination between 20/0 to 25/0 weeks of gestation to prevent preterm birth. Median intervention-to-birth interval was the primary endpoint. RESULTS: 231 of 424 pregnant women had a cerclage only (54.5%), 76 women a pessary only (17.9%), and 27 were prescribed progesterone only (15.3%). The most common combination treatment (>1 intervention group) was cerclage plus progesterone (n=27), followed by cerclage plus pessary (n=13). The median intervention-to-birth interval for the whole cohort was 24 days (IQR 19.0 days). The earlier the intervention was started, the longer the intervention-to-birth interval lasted: When started at 20 weeks, the interval was 34 days in contrast to 11.5 days, when started at 25 weeks. The >1 group was born at a significantly higher median GA with 27.0 weeks (IQR 2.9 weeks) and a higher median birth weight of 980 g (IQR 394 g) accordingly. CONCLUSION: We propose that the earliest possible start of intervention leads to the most efficient pregnancy prolongation.

Ureaplasma-Driven Neonatal Neuroinflammation: Novel Insights from an Ovine Model.

Ureaplasma species (spp.) are considered commensals of the adult genitourinary tract, but have been associated with chorioamnionitis, preterm birth, and invasive infections in neonates, including meningitis. Data on mechanisms involved in Ureaplasma-driven neuroinflammation are scarce. The present study addressed brain inflammatory responses in preterm lambs exposed to Ureaplasma parvum (UP) in utero. 7 days after intra-amniotic injection of UP (n = 10) or saline (n = 11), lambs were surgically delivered at gestational day 128-129. Expression of inflammatory markers was assessed in different brain regions using qRT-PCR and in cerebrospinal fluid (CSF) by multiplex immunoassay. CSF was analyzed for UP presence using ureB-based real-time PCR, and MRI scans documented cerebral white matter area and cortical folding. Cerebral tissue levels of atypical chemokine receptor (ACKR) 3, caspases 1-like, 2, 7, and C-X-C chemokine receptor (CXCR) 4 mRNA, as well as CSF interleukin-8 protein concentrations were significantly increased in UP-exposed lambs. UP presence in CSF was confirmed in one animal. Cortical folding and white matter area did not differ among groups. The present study confirms a role of caspases and the transmembrane receptors ACKR3 and CXCR4 in Ureaplasma-driven neuroinflammation. Enhanced caspase 1-like, 2, and 7 expression may reflect cell death. Increased ACKR3 and CXCR4 expression has been associated with inflammatory central nervous system (CNS) diseases and impaired blood-brain barrier function. According to these data and previous in vitro findings from our group, we speculate that Ureaplasma-induced caspase and receptor responses affect CNS barrier properties and thus facilitate neuroinflammation.

Validation of disease-specific biomarkers for the early detection of bronchopulmonary dysplasia.

OBJECTIVE: To demonstrate and validate the improvement of current risk stratification for bronchopulmonary dysplasia (BPD) early after birth by plasma protein markers (sialic acid-binding Ig-like lectin 14 (SIGLEC-14), basal cell adhesion molecule (BCAM), angiopoietin-like 3 protein (ANGPTL-3)) in extremely premature infants. METHODS AND RESULTS: Proteome screening in first-week-of-life plasma samples of n = 52 preterm infants <32 weeks gestational age (GA) on two proteomic platforms (SomaLogic®, Olink-Proteomics®) confirmed three biomarkers with significant predictive power: BCAM, SIGLEC-14, and ANGPTL-3. We demonstrate high sensitivity (0.92) and specificity (0.86) under consideration of GA, show the proteins' critical contribution to the predictive power of known clinical risk factors, e.g., birth weight and GA, and predicted the duration of mechanical ventilation, oxygen supplementation, as well as neonatal intensive care stay. We confirmed significant predictive power for BPD cases when switching to a clinically applicable method (enzyme-linked immunosorbent assay) in an independent sample set (n = 25, p < 0.001) and demonstrated disease specificity in different cohorts of neonatal and adult lung disease. CONCLUSION: While successfully addressing typical challenges of clinical biomarker studies, we demonstrated the potential of BCAM, SIGLEC-14, and ANGPTL-3 to inform future clinical decision making in the preterm infant at risk for BPD. TRIAL REGISTRATION: Deutsches Register Klinische Studien (DRKS) No. 00004600; https://www.drks.de . IMPACT: The urgent need for biomarkers that enable early decision making and personalized monitoring strategies in preterm infants with BPD is challenged by targeted marker analyses, cohort size, and disease heterogeneity. We demonstrate the potential of the plasma proteins BCAM, SIGLEC-14, and ANGPTL-3 to identify infants with BPD early after birth while improving the predictive power of clinical variables, confirming the robustness toward proteome assays and proving disease specificity. Our comprehensive analysis enables a phase-III clinical trial that allows full implementation of the biomarkers into clinical routine to enable early risk stratification in preterms with BPD.

SARS-CoV-2 sero-immunity and quality of life in children and adolescents in relation to infections and vaccinations: the IMMUNEBRIDGE KIDS cross-sectional study, 2022.

PURPOSE: The study evaluates the effects on sero-immunity, health status and quality of life of children and adolescents after the upsurge of the Omicron variant in Germany. METHODS: This multicenter cross-sectional study (IMMUNEBRIDGE Kids) was conducted within the German Network University Medicine (NUM) from July to October 2022. SARS-CoV-2- antibodies were measured and data on SARS-CoV-2 infections, vaccinations, health and socioeconomic factors as well as caregiver-reported evaluation on their children's health and psychological status were assessed. RESULTS: 497 children aged 2-17 years were included. Three groups were analyzed: 183 pre-schoolchildren aged 2-4 years, 176 schoolchildren aged 5-11 years and 138 adolescents aged 12-18 years. Positive antibodies against the S- or N-antigen of SARS-CoV-2 were detected in 86.5% of all participants (70.0% [128/183] of pre-schoolchildren, 94.3% of schoolchildren [166/176] and 98.6% of adolescents [136/138]). Among all children, 40.4% (201/497) were vaccinated against COVID-19 (pre-schoolchildren 4.4% [8/183], schoolchildren 44.3% [78/176] and adolescents 83.3% [115/138]). SARS-CoV-2 seroprevalence was lowest in pre-school. Health status and quality of life reported by the parents were very positive at the time of the survey (Summer 2022). CONCLUSION: Age-related differences on SARS-CoV-2 sero-immunity could mainly be explained by differences in vaccination rates based on the official German vaccination recommendations as well as differences in SARS-CoV-2 infection rates in the different age groups. Health status and quality of life of almost all children were very good independent of SARS-CoV-2 infection and/or vaccination. TRIAL REGISTRATION: German Registry for Clinical Trials Identifier Würzburg: DRKS00025546 (registration: 11.09.2021), Bochum: DRKS00022434 (registration:07.08.2020), Dresden: DRKS 00022455 (registration: 23.07.2020).

Erythrocyte transfusions are associated with retinopathy of prematurity in extremely low gestational age newborns.

AIM: Retinopathy of prematurity (ROP) is a major morbidity in preterm infants causing visual impairment including blindness. Prevention and timely treatment are critical. We investigated the potential role of red blood cell (RBC) transfusions as risk factor for ROP development. METHODS: Retrospective cohort study of data from 68 tertiary level neonatal intensive care units in Germany. Preterm infants born at 22 + 0 to 28 + 6 weeks of gestation between January 2009 and December 2021 were enrolled. RESULTS: We included n = 12 565 infants. Prevalence of any ROP was 49.2% with most infants being diagnosed with stage 1 (21.5%) and 2 disease (17.2%). ROP stage 3 was present in 10.2%, stage 4 in 0.3%, and ROP requiring treatment in 6.6%. Infants with ROP had significantly more frequently a history of RBC transfusions. Adjusting for confounders, RBC transfusions were associated with increased odds of ROP (OR 1.4, p < 0.001), ROP progression (OR 2.1, p < 0.01) and ROP requiring treatment (OR 3.6, p < 0.001). Restrictive transfusion approaches correlated with decreased (OR 0.7, p < 0.001), liberal regimes with increased odds (OR 1.2, p = 0.001). CONCLUSION: The present study confirmed an association of RBC transfusions and ROP. Our findings emphasise the need for anaemia prevention and critical re-evaluation of transfusion practices in preterm infants.

Increased Expression of Anaphylatoxin C5a-Receptor-1 in Neutrophils and Natural Killer Cells of Preterm Infants.

Preterm infants are susceptible to infection and their defense against pathogens relies largely on innate immunity. The role of the complement system for the immunological vulnerability of preterm infants is less understood. Anaphylatoxin C5a and its receptors C5aR1 and -2 are known to be involved in sepsis pathogenesis, with C5aR1 mainly exerting pro-inflammatory effects. Our explorative study aimed to determine age-dependent changes in the expression of C5aR1 and C5aR2 in neonatal immune cell subsets. Via flow cytometry, we analyzed the expression pattern of C5a receptors on immune cells isolated from peripheral blood of preterm infants (n = 32) compared to those of their mothers (n = 25). Term infants and healthy adults served as controls. Preterm infants had a higher intracellular expression of C5aR1 on neutrophils than control individuals. We also found a higher expression of C5aR1 on NK cells, particularly on the cytotoxic CD56dim subset and the CD56- subset. Immune phenotyping of other leukocyte subpopulations revealed no gestational-age-related differences for the expression of and C5aR2. Elevated expression of C5aR1 on neutrophils and NK cells in preterm infants may contribute to the phenomenon of "immunoparalysis" caused by complement activation or to sustained hyper-inflammatory states. Further functional analyses are needed to elucidate the underlying mechanisms.

Imbalanced Inflammatory Responses in Preterm and Term Cord Blood Monocytes and Expansion of the CD14+CD16+ Subset upon Toll-like Receptor Stimulation.

Developmentally regulated features of innate immunity are thought to place preterm and term infants at risk of infection and inflammation-related morbidity. Underlying mechanisms are incompletely understood. Differences in monocyte function including toll-like receptor (TLR) expression and signaling have been discussed. Some studies point to generally impaired TLR signaling, others to differences in individual pathways. In the present study, we assessed mRNA and protein expression of pro- and anti-inflammatory cytokines in preterm and term cord blood (CB) monocytes compared with adult controls stimulated ex vivo with Pam3CSK4, zymosan, polyinosinic:polycytidylic acid, lipopolysaccharide, flagellin, and CpG oligonucleotide, which activate the TLR1/2, TLR2/6, TLR3, TLR4, TLR5, and TLR9 pathways, respectively. In parallel, frequencies of monocyte subsets, stimulus-driven TLR expression, and phosphorylation of TLR-associated signaling molecules were analyzed. Independent of stimulus, pro-inflammatory responses of term CB monocytes equaled adult controls. The same held true for preterm CB monocytes-except for lower IL-1ß levels. In contrast, CB monocytes released lower amounts of anti-inflammatory IL-10 and IL-1ra, resulting in higher ratios of pro-inflammatory to anti-inflammatory cytokines. Phosphorylation of p65, p38, and ERK1/2 correlated with adult controls. However, stimulated CB samples stood out with higher frequencies of intermediate monocytes (CD14+CD16+). Both pro-inflammatory net effect and expansion of the intermediate subset were most pronounced upon stimulation with Pam3CSK4 (TLR1/2), zymosan (TR2/6), and lipopolysaccharide (TLR4). Our data demonstrate robust pro-inflammatory and yet attenuated anti-inflammatory responses in preterm and term CB monocytes, along with imbalanced cytokine ratios. Intermediate monocytes, a subset ascribed pro-inflammatory features, might participate in this inflammatory state.

[Pregnant in the Intensive Care Unit]. / Schwanger auf der Intensivstation.

Although admission to an intensive care unit during pregnancy is rare, pregnant women may become critically ill due to either obstetric or non-obstetric illness. Whilst critical illness due to obstetric reasons during the peripartum period (e.g. peripartum haemorrhage, HELLP-syndrome) is more common, it is also important to know how to care for critically ill pregnant women with non-obstetric illness (e.g. infection, cardiovascular diseases, neurological diseases, trauma). Physiological changes during pregnancy may affect critical care treatment, variation in standard and target values for blood pressure management or artificial ventilation. Pregnancy specific reference values in interpretation of blood chemistry are important issues to consider. The use of different drugs is inevitable in critical care, knowing which drugs are safe to use during the different stages of pregnancy is essential. Caring for mother and unborn child in the ICU is a challenge, open communication, ethical considerations and interdisciplinary as well as multiprofessional collaborations should be key points when caring for critically ill pregnant patients.

Association of ApoE Genotypes and Recovery From Intracerebral Hemorrhage in Very Low Birth Weight Infants.

BACKGROUND AND PURPOSE: Associations of APOE genotypes with intracerebral hemorrhage (ICH) in preterm infants were previously described. In adults, APOE-ε4 genotype has been proposed as susceptibility factor for impaired recovery after cerebral insult. We here aim to determine APOE genotype-specific neurological consequences of neonatal ICH at school age. METHODS: In this multicenter observational cohort study, very low birth weight (<1500 g, <32 weeks gestational age) children were studied for cerebral palsy (CP) after ultrasound diagnosed ICH stratified by APOE genotype. Follow-up examination was done at the age of 5 to 6 years. Study personnel were blinded for perinatal information and complications. Participants were born between January 1, 2009 and December 31, 2013 and enrolled in the German Neonatal Network. Of 8022 infants primarily enrolled, 2467 children were invited for follow-up between January 1, 2014 and December 31, 2019. Univariate analyses and multivariate logistic regression models were used to assess the impact of APOE genotype (APOE-ε2, APOE-ε3, APOE-ε4) on CP after ICH. RESULTS: Two thousand two hundred fifteen children participated at follow-up, including 363 children with ultrasound diagnosed neonatal ICH. In univariate analyses of children with a history of ICH, APOE-ε3 carriers had lower frequencies of CP (n=33/250; 13.2 [95% CI, 9.4%-17.8%]), as compared to APOE-ε2 (n=15/63; 23.8 [14.6%-35.3%], P=0.037) and -ε4 carriers (n=31/107; 29.0 [21.0%-38.0%], P<0.001), respectively. Regression models revealed an association of APOE-ε4 genotype and CP development (odds ratio, 2.77 [1.44-5.32], P=0.002) after ICH. Notably, at low-grade ICH (grade I) APOE-ε4 expression resulted in an increased rate of CP (n=6/39; 15.4 [6.7-29.0]) in comparison to APOE-ε3 (n=2/105; 1.9 [0.4%-6.0%], P=0.002). CONCLUSIONS: APOE-ε4 carriers have an increased risk for long-term motor deficits after ICH. We assume an effect even after low-grade neonatal ICH, but more data are needed to clarify this issue.

Multi-centre 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 1 s (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 multi-centre, 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.

Two Beer(s) or Not Two Beer(s): The eNose as an Instrument to Pacify the World.

BACKGROUND: Science prizes that are not meant to be very serious, stand-up evenings, science slams or publications with a scientific twist: science comedy comes in very different forms. But all variants have one thing in common: humour. It can be used to hide the seriousness of life or, in this case, everyday scientific life for a brief moment. Moreover, serious social or ethical questions are also met. The GPP, a group of German, Austrian and Swiss Pediatric Pulmonologists (GPP) is a scientific society with regular annual meetings. Unsystematic observations and preliminary data suggest that beer consumption increased by some of the participants during this event. Recently, electronic nose (eNose) devices have been developed as a technology for disease screening using exhaled-breath analysis. Here we addressed the issue, if the eNose can be used to differentiate between real beer and fake beer. METHODS: In this single-centre experimental study, 12 different "real beer" types and one "fake beer" were analyzed with regard to their emittance of volatile organic compounds (VOCs) with the eNose as an electronic VOC-sensing technology. RESULTS: Every single beer type can be identified by a characteristic VOC-smell print using the eNose. Distinct clusters exist for bottom- and top-fermented ales. Intriguingly, "Sylter Hopfen", which is marketed as a "champagne-beer" and tested as representative of a "fake beer", can be clearly differentiated from all other genuine beer types. CONCLUSION: Our study provides the first objective data of beer flavor. In the long term perspective the eNose might help to overcome the agonizing controversy about beer flavors and, consequently, pacify the World. In the short run, however, our results give support to more targeted and reserved beer consumption during our annual meeting, especially since one specific beer shows a very similar pattern to indoor air. HINTERGRUND UND FRAGESTELLUNG: Sogenannte Stand-up-Abende, Science Slams oder Publikationen wie in der «Christmas-Edition¼ des "British Medical Journals" haben eines gemeinsam: Humor. Humor kann dabei helfen, der Ernsthaftigkeit des Alltags - auch der des Wissenschaftlers - für einen kurzen Moment zu entfliehen. Die wissenschaftliche Gesellschaft Pädiatrische Pneumologie (GPP e. V.) ist eine Gruppe deutscher, österreichischer und schweizer Kinderpneumolog:innen, die sich regelmässig zu ihrer Jahrestagung treffen. Nicht-systematisch erhobene Daten und persönliche Beobachtungen deuten darauf hin, dass der Bierkonsum von einigen der Teilnehmer:innen während dieser Veranstaltung signifikant ansteigt. Vor kurzem wurde mit der «eNose¼ eine sogenannte «elektronische Nase¼ entwickelt, die als Screening-Instrument zur Atemgasanalyse eingesetzt werden kann. Hier haben wir die Frage gestellt, ob die eNose verwendet werden kann, um unterschiedliche Biersorten zu unterscheiden und echte Biere von sogenannten «Fake-Bieren¼ zu diskriminieren. METHODEN: In dieser monozentrischen, experimentellen Studie wurden 12 verschiedene "echte Biersorten" und ein "Fake-Bier" hinsichtlich ihrer Emission flüchtiger organischer Verbindungen (VOCs) mit der eNose als elektronische VOC-Sensortechnologie analysiert. ERGEBNISSE: Jede einzelne Biersorte lässt sich anhand eines charakteristischen, reproduzierbaren VOC-Profils mit der eNose identifizieren. Dabei clustern sogenannte unter- und obergärige Biere mit einem spezifischen Muster. "Sylter Hopfen", das als "Champagner-Bier" vermarktet und als «Fake-Bier¼ getestet wurde, unterscheidet sich in seinem VOC-Profil von allen anderen «echten¼ Biersorten. SCHLUSSFOLGERUNG: Unsere Studie liefert die ersten objektiven Daten zu spezifischen VOC-Mustern von verschiedenen Biersorten. Langfristig könnte die eNose dabei helfen, die emotionale Kontroverse um Bieraromen zu überwinden und damit die Welt zu befrieden. Kurzfristig stützen unsere Ergebnisse die Empfehlung nach einem zurückhaltenden Bierkonsum während unserer Jahrestagung, zumal spezifischen VOC-Mustern einiger Biere ein sehr ähnliches Muster wie Raumluft zeigen.

[Postpartum hemorrhage : Interdisciplinary consideration in the context of patient blood management]. / Postpartale Hämorrhagie : Interdisziplinäre Betrachtung im Kontext des Patient Blood Management.

Postpartum hemorrhage (PPH) nowadays still represents a severe complication of both a vaginal delivery and a cesarean section. In German-speaking areas a new definition of the term has recently become established and the nomenclature with respect to the severe form of PPH was dropped. The handling of misoprostol as a uterotonic during treatment of PPH is also new, which is available in Germany only as a medical direct import. For adequate diagnostics and targeted treatment interdisciplinary and standardized algorithms should be established and the specialist disciplines involved should be sensitized to this problem. In addition to an adequate hemostasis, a developing coagulopathy must be recognized at an early stage and treated with targeted coagulation management. Through implementation concepts, particularly the second pillar (minimization of blood loss) and the third pillar (rational use of blood transfusions) of patient blood management, various aspects for improvement of treatment of a PPH can be identified.

[Patient blood management in the preparation for birth, obstetrics and postpartum period]. / Patient Blood Management in der Geburtsvorbereitung, Geburtshilfe und postpartalen Phase.

The implementation of patient blood management (PBM) is increasingly becoming standard in operative medicine. Recently, interest has also been shown for the vulnerable collective of pregnant women and neonates. As the information regarding anesthesiological procedures for pregnant women and the peripartum period including an informed consent process should be carried out long before childbirth, this provides a good possibility in this connection to incorporate PBM. An anesthesiological risk estimation as well as the diagnostic workup and treatment of potential anemia should be carried out during the pregnancy. Furthermore, loss of blood in anticipation of bleeding complications should be reduced by interdisciplinary preventive measures and an individually coordinated postpartum care should be organized. This results in an early diagnosis of anemia or iron deficiency with subsequent treatment also postpartum, analogous to the prepartum period.

S100A8 and S100A9 Are Important for Postnatal Development of Gut Microbiota and Immune System in Mice and Infants.

BACKGROUND & AIMS: After birth, the immune system matures via interactions with microbes in the gut. The S100 calcium binding proteins S100A8 and S100A9, and their extracellular complex form, S100A8-A9, are found in high amounts in human breast milk. We studied levels of S100A8-A9 in fecal samples (also called fecal calprotectin) from newborns and during infancy, and their effects on development of the intestinal microbiota and mucosal immune system. METHODS: We collected stool samples (n = 517) from full-term (n = 72) and preterm infants (n = 49) at different timepoints over the first year of life (days 1, 3, 10, 30, 90, 180, and 360). We measured levels of S100A8-A9 by enzyme-linked immunosorbent assay and analyzed fecal microbiomes by 16S sRNA gene sequencing. We also obtained small and large intestine biopsies from 8 adults and 10 newborn infants without inflammatory bowel diseases (controls) and 8 infants with necrotizing enterocolitis and measured levels of S100A8 by immunofluorescence microscopy. Children were followed for 2.5 years and anthropometric data and medical information on infections were collected. We performed studies with newborn C57BL/6J wild-type and S100a9-/- mice (which also lack S100A8). Some mice were fed or given intraperitoneal injections of S100A8 or subcutaneous injections of Staphylococcus aureus. Blood and intestine, mesenterial and celiac lymph nodes were collected; cells and cytokines were measured by flow cytometry and studied in cell culture assays. Colon contents from mice were analyzed by culture-based microbiology assays. RESULTS: Loss of S100A8 and S100A9 in mice altered the phenotypes of colonic lamina propria macrophages, compared with wild-type mice. Intestinal tissues from neonatal S100-knockout mice had reduced levels of CX3CR1 protein, and Il10 and Tgfb1 mRNAs, compared with wild-type mice, and fewer T-regulatory cells. S100-knockout mice weighed 21% more than wild-type mice at age 8 weeks and a higher proportion developed fatal sepsis during the neonatal period. S100-knockout mice had alterations in their fecal microbiomes, with higher abundance of Enterobacteriaceae. Feeding mice S100 at birth prevented the expansion of Enterobacteriaceae, increased numbers of T-regulatory cells and levels of CX3CR1 protein and Il10 mRNA in intestine tissues, and reduced body weight and death from neonatal sepsis. Fecal samples from term infants, but not preterm infants, had significantly higher levels of S100A8-A9 during the first 3 months of life than fecal samples from adults; levels decreased to adult levels after weaning. Fecal samples from infants born by cesarean delivery had lower levels of S100A8-A9 than from infants born by vaginal delivery. S100 proteins were expressed by lamina propria macrophages in intestinal tissues from infants, at higher levels than in intestinal tissues from adults. High fecal levels of S100 proteins, from 30 days to 1 year of age, were associated with higher abundance of Actinobacteria and Bifidobacteriaceae, and lower abundance of Gammaproteobacteria-particularly opportunistic Enterobacteriaceae. A low level of S100 proteins in infants' fecal samples associated with development of sepsis and obesity by age 2 years. CONCLUSION: S100A8 and S100A9 regulate development of the intestinal microbiota and immune system in neonates. Nutritional supplementation with these proteins might aide in development of preterm infants and prevent microbiota-associated disorders in later years.

Aminoglycosides were associated with higher rates of surgical patent ductus arteriosus closure in preterm infants.

AIM: In animal studies, aminoglycosides induced ductus arteriosus relaxation in a dose-dependent fashion. We tested the hypothesis that antibiotic treatment of preterm infants with aminoglycosides is associated with higher rates of surgical patent ductus arteriosus (PDA) closure. METHODS: Preterm infants (birthweight <1000 grams or gestational age <29 weeks) enrolled in 62 German neonatal intensive care units (NICUs) were analysed. NICUs were stratified according to the use of aminoglycosides as first-line antibiotics. RESULTS: Baseline data were not different when NICUs using aminoglycosides (n = 9965 infants) were compared to NICUs using other antibiotics (n = 1948 infants). Rates of surgical PDA closure were 5.9% for NICUs using aminoglycosides; 6.2% for units using gentamicin; and 5.0% for NICUs using tobramycin compared to 4.1% in NICUs using other antibiotics (P < .001, P < .001 and P = .140, respectively, Fisher's exact test). Indomethacin and ibuprofen use was more common in NICUs using aminoglycosides (41% vs 33%, P < .001, Fisher's exact test). Gentamicin trough levels were higher in NICUs with surgical closure rates above the mean (median 2.0 µg/mL, inter-quartile range 0.8-4.0 µg/mL vs 1.2 µg/mL, IQR 0.8-1.7, P < .001, Mann-Whitney U test). CONCLUSION: First-line antibiotic treatment of preterm infants with aminoglycosides was associated with higher rates of surgical PDA closure.

Vancomycin-induced ototoxicity in very-low-birthweight infants.

BACKGROUND: Vancomycin is an extensively used anti-infective drug in neonatal ICUs. However, exposure-toxicity relationships have not been clearly defined. OBJECTIVES: To evaluate the risk profile for hearing deficits in vancomycin-exposed very-low-birthweight infants (VLBWI). METHODS: In a large cohort study of the German Neonatal Network (GNN; n = 16 967 VLBWI) we assessed the association of vancomycin treatment and pathological hearing tests at discharge and at 5 year follow-up. We performed audits on vancomycin exposure, drug levels, dose adjustments and exposure to other ototoxic drugs in a subgroup of 1042 vancomycin-treated VLBWI. RESULTS: In the GNN cohort, 28% (n = 4739) were exposed to IV vancomycin therapy. In multivariable logistic regression analysis, vancomycin exposure proved to be independently associated with pathological hearing test at discharge (OR 1.18, 95% CI 1.03-1.34, P = 0.016). Among vancomycin-treated infants, a cumulative vancomycin dose above the upper quartile (>314 mg/kg bodyweight) was associated with pathological hearing test at discharge (OR 2.1, 95% CI 1.21-3.64, P = 0.009), whereas a vancomycin cumulative dose below the upper quartile was associated with a reduced risk of pathological tone audiometry results at 5 years of age (OR 0.29, 95% CI 0.1-0.8, P = 0.02, n = 147). CONCLUSIONS: Vancomycin exposure in VLBWI is associated with an increased, dose-dependent risk of pathological hearing test results at discharge and at 5 years of age. Prospective studies on long-term hearing impairment are needed.