Epidemiology of 7375 children and adolescents hospitalized with COVID-19 in Germany, reported via a prospective, nationwide surveillance study in 2020-2022.

By means of a nationwide, prospective, multicenter, observational cohort registry collecting data on 7375 patients with laboratory-confirmed SARS-CoV-2 admitted to children's hospitals in Germany, March 2020-November 2022, our study assessed the clinical features of children and adolescents hospitalized due to SARS-CoV-2, evaluated which of these patients might be at highest risk for severe COVID-19, and identified underlying risk factors. Outcomes tracked included: symptomatic infection, case fatality, sequelae at discharge and severe disease. Among reported cases, median age was one year, with 42% being infants. Half were admitted for reasons other than SARS-CoV-2. In 27%, preexisting comorbidities were present, most frequently obesity, neurological/neuromuscular disorders, premature birth, and respiratory, cardiovascular or gastrointestinal diseases. 3.0% of cases were admitted to ICU, but ICU admission rates varied as different SARS-CoV-2 variants gained prevalence. Main risk factors linked to ICU admission due to COVID-19 were: patient age (> 12 and 1-4 years old), obesity, neurological/neuromuscular diseases, Trisomy 21 or other genetic syndromes, and coinfections at time of hospitalization. With Omicron, the group at highest risk shifted to 1-4-year-olds. For both health care providers and the general public, understanding risk factors for severe disease is critical to informing decisions about risk-reduction measures, including vaccination and masking guidelines.

High burden of acute respiratory tract infections leading to hospitalization at German pediatric hospitals: fall/winter 2022-2023.

PURPOSE: Given reduced immunity levels for seasonally occurring respiratory infections and the experience of an unusually early, severe wave of RSV infections during 2021, a preexisting clinician-led reporting system (CLRS) was updated to prospectively monitor the anticipated high burden of respiratory infections (ARI) in German pediatric hospitals during fall/winter 2022-2023. METHODS: From September 13, 2022 through March 31, 2023, children hospitalized with ARI as a primary diagnosis were monitored via a national CLRS established by the German Society for Pediatric Infectious Diseases (DGPI). Once a week, the CLRS collected overall number of new hospital admissions, ARI-related admissions according to pathogen (SARS-CoV-2, RSV, influenza, and other), plus number of patients admitted to ICU with ARI as a primary diagnosis. RESULTS: With a high participation among children's hospitals across Germany (22.8%), 76 centers submitted 1,053 survey reports. ARI-related hospital admissions showed a steep rise starting in late September 2022 and reached their highpoint in early December 2022 (50.1% of all admissions). In parallel, the average number of newly admitted patients (aNA) with RSV (3.6) peaked, as did those with influenza (2.1) one week later. The average highpoint of ARI patients on ICU (aICU) (2.9) was reached shortly thereafter. Again, RSV (1.6) und influenza (1.2) were predominant pathogens. CONCLUSION: In fall/winter 2022-2023, German hospitals reported a sharp increase in patients with ARIs. While RSV and influenza represented the greatest proportion of ARI, SARS-CoV-2 played a less significant role. Systematic, dynamic collection of ARI data is critical for assessing real burdens on the health care system.

A comparison of pediatric inflammatory multisystem syndrome temporarily-associated with SARS-CoV-2 and Kawasaki disease.

The connection between Pediatric Inflammatory Multisystem Syndrome (PIMS) and Kawasaki Disease (KD) is not yet fully understood. Using the same national registry, clinical features and outcome of children hospitalized in Germany, and Innsbruck (Austria) were compared. Reported to the registry were 395 PIMS and 69 KD hospitalized patients. Patient age in PIMS cases was higher than in KD cases (median 7 [IQR 4-11] vs. 3 [IQR 1-4] years). A majority of both PIMS and KD patients were male and without comorbidities. PIMS patients more frequently presented with organ dysfunction, with the gastrointestinal (80%), cardiovascular (74%), and respiratory (52%) systems being most commonly affected. By contrast, KD patients more often displayed dermatological (99% vs. 68%) and mucosal changes (94% vs. 64%), plus cervical lymph node swelling (51% vs. 34%). Intensive care admission (48% vs. 19%), pulmonary support (32% vs. 10%), and use of inotropes/vasodilators (28% vs. 3%) were higher among PIMS cases. No patients died. Upon patient discharge, potentially irreversible sequelae-mainly cardiovascular-were reported (7% PIMS vs. 12% KD). Despite differences in age distribution and disease severity, PIMS and KD cases shared many common clinical and prognostic characteristics. This supports the hypothesis that the two entities represent a syndrome continuum.

Evaluating the Effect of a Neonatal Care Bundle for the Prevention of Intraventricular Hemorrhage in Preterm Infants.

Germinal matrix intraventricular hemorrhage (IVH) remains a severe and common complication in preterm infants. A neonatal care bundle (NCB) was implemented as an in-house guideline at a tertiary neonatal intensive care unit to reduce the incidence of IVH in preterm infants. The NCB was applied either to preterm infants <1250 g birth weight or <30 weeks gestational age or both, and standardized patient positioning, nursing care, and medical procedures within the first week of life. A retrospective cohort study was performed to investigate the effect of the NCB and other known risk factors on the occurrence and severity of IVH. Data from 229 preterm infants were analyzed. The rate of IVH was 26.2% before and 27.1% after implementing the NCB. The NCB was associated neither with reducing the overall rate of IVH (odds ratio (OR) 1.02; 95% confidence interval (CI) 0.57-1.84; p = 0.94) nor with severe IVH (OR 1.0; 95% CI 0.67-1.55; p = 0.92). After adjustment for group differences and other influencing factors, amnion infection syndrome and early intubation were associated with an increased risk for IVH. An NCB focusing on patient positioning, nursing care, and medical interventions had no impact on IVH in preterm infants. Known risk factors for IVH were confirmed.

[Quality of Care for Very Low Birth Weight Infants in Germany - Evaluation of Publicly Available Data from 2014 to 2018]. / Qualität der Versorgung sehr kleiner Frühgeborener in Deutschland ­ Auswertung öffentlich verfügbarer Daten der Perinatalzentren von 2014 bis 2018.

INTRODUCTION: Since 2014 outcome data for the treatment of very low birth weight (VLBW) infants in Germany have been available at www.perinatalzentren.org. This study explores the relationship between volume of VLBW infants and outcome. METHODS: Volumes of VLBW infants for each perinatal centre are available for the 5-year period from 2014 to 2018, and survival and survival without severe morbidity in relation to the national average survival rate is reported. In addition to volume an adjusted volume is specified considering several risk factors. Using regression, the relationship between volume, adjusted volume and survival was investigated. RESULTS: Of 212 perinatal centres 163 (77%) were level 1 centres (highest level in Germany) and 49 (23%) were level 2 centres caring for 9300 (94%; median 51; min 13 max 186) and 538 (6%; 9; 4-28) VLBW infants per year, respectively. No significant correlation between volume and survival and survival w/o severe morbidity was found. Adjusted volumes showed a weak linear correlation to survival w/o severe morbidity (p=0.02, R2=0.03). Non-parametric regression was significant for adjusted volumes of more than 170 (survival) and 100 (survival w/o severe morbidity) VLBW infants per year and centre, respectively. Below these limits volume does not affect variation. CONCLUSION: Linear and non-linear regression between adjusted volumes and survival was only weak and was driven by the very large perinatal centres.

[Preterm Birth Rate at 6 Centres for Perinatal Medicine in Baden-Württemberg - Potential to Reduce Prematurity]. / Frühgeburtenrate in 6 Perinatalzentren in Baden-Württemberg ­ Potential zur Reduktion der Frühgeborenenzahl.

BACKGROUND: The Federal Joint Committee of Germany defined structural and staff requirements for the care of preterm and term infants as a proxy measure for quality. Neonatal outcome has been evaluated as a quality marker for a long time. While Germany has one of the highest preterm birth rates in Europe, no data exist on centre-specific preterm birth rates. METHODS: Over 2 years, all pregnant women admitted to six centres for perinatal medicine in Baden-Württemberg at a gestational age between 22+0 and 31+6 weeks were eligible (n=2972). The preterm birth rate before 32 wks of gestation was evaluated if at least one of the following secondary inclusion criteria was present within 24 h after admission: 1) premature rupture of membranes, 2) cervical length less than 25 mm, or 3) more than 3 contractions of at least 30-s duration within a 30-min period. Neonatal outcome could be documented for 70.6% of infants. RESULTS: Of the women who met at least one secondary inclusion criterion (n=1325), 21.1% (n=279) delivered 344 preterm infants before 32 weeks. The preterm birth rate was between 16.8 and 27.9% (11.1% difference). A lower preterm birth rate was not associated with a worse neonatal outcome. CONCLUSION: Preterm birth rate should become a quality indicator for perinatal care. A reduction of the preterm birth rate of 5% could help to reduce the number of preterm infants by up to 2,400 per year in Germany (about 25%).

Neurodevelopmental follow-up at five years corrected age of extremely low birth weight infants after postnatal replacement of 17ß-estradiol and progesterone.

CONTEXT: Extremely low birth weight (ELBW) infants are prone to impaired neurodevelopment. OBJECTIVE: The aim was to determine long-term neurodevelopmental outcome in ELBW infants after postnatal 17ß-estradiol (E2) and progesterone (P) replacement. DESIGN: At 5-yr corrected age, ELBW infants were assessed for standardized cognitive and neurological outcome after postnatal randomized E2 and P replacement or placebo administration. SETTING: The follow-up examination was performed in a neuropediatric ambulatory care center. PATIENTS: Sixty-one of 71 surviving infants (86%) were available for follow-up. MAIN OUTCOME MEASURES: Cognitive and neurological outcome was evaluated using the Kaufmann Assessment Battery for Children, the Gross Motor Function Classification Scale, and clinical neurological examination. RESULTS: No significant differences were found between the replacement and placebo groups for the Gross Motor Function Classification Scale, presence of paresis, cerebral palsy, spasticity, and ametropia. However, a significant time-response relationship was found with E2 and P replacement. Every day of treatment reduced the risk for cerebral palsy (P=0.03), spasticity (P=0.01), and ametropia (P=0.01). CONCLUSION: Postnatal E2 and P replacement may have potential in improving neurodevelopmental outcome in ELBW infants. Larger trials are needed to test this new hypothesis.

Combined application of 17beta-estradiol and progesterone enhance vascular endothelial growth factor and surfactant protein expression in cultured embryonic lung cells of mice.

Preterm delivery is associated with disruption of the placental supply with 17beta-estradiol (E2) and progesterone (P). The aim is to evaluate the role of E2 and P on the regulation of key proteins in lung development in embryonic lung cells. Alveolar cell type II (AT-II) and central lung fibroblast cultures were established from mouse embryos. Cells were exposed for 24 hours to E2 and/or P, the estrogen receptor antagonist ICI 182.780 (ICI) and the progesterone receptor antagonist mifepristone (RU 486). The mRNA expression of vascular endothelial growth factor (VEGF) and surfactant protein B and C (SB-B, SB-C) was determined, and protein levels of VEGF were measured. Only the combined treatment with E2 and P increased mRNA expression and VEGF protein in AT-II cells and lung fibroblasts. Combined treatment also promoted SP-B and SP-C expression in AT-II cells. Pretreatment with ICI and RU 486 completely abolished the E2 and P induced effects. E2 and P enhanced expression of VEGF and surfactant proteins in primary embryonic lung cells and may be involved in regulating expression of key molecules for the prenatal lung development and postnatal lung function.

Gender-related effects of prenatal administration of estrogen and progesterone receptor antagonists on VEGF and surfactant-proteins and on alveolarisation in the developing piglet lung.

BACKGROUND: Vascular endothelial growth factor (VEGF) is essential for embryonic lung development and has been shown to be regulated by estradiol (E2) and progesterone (P). AIM: To investigate the effects of prenatal E2 and P withdrawal by specific receptor antagonists on the mRNA expression of VEGF, surfactant proteins (SP-B and SP-C) and on alveolarisation in lung tissue of male and female pig fetuses. METHODS: Fetuses from 10 sows were randomized to receive either both an intramuscular injection of the E2 receptor blocker ICI 182.780 and the P receptor blocker RTI 3021-022 (ICI+RTI, n=5) or a placebo injection (n=5) at 90 days of gestation (DOG, 115=term). After delivery by cesarean section on 114 DOG, tissue of the left lingula of the piglet's lung (28 placebo, 26 ICI+RTI) was obtained to determine the mRNA expression of VEGF, SP-B and SP-C. Lungs from 15 placebo and 14 ICI+RTI group piglets were removed and alveolar counts performed. RESULTS: The ICI+RTI group showed significantly lower SP-C mRNA expression and alveolar counts compared to the placebo group (p=0.04 and 0.03, respectively). Diminished alveolarisation in the ICI+RTI group was mainly due to the reduction of alveolar counts in male piglets (p=0.02). Within the placebo group VEGF and SP-B mRNA expression in male piglets were significantly lower compared to female piglets (p=0.01 and 0.004, respectively). ICI+RTI treatment abolished this gender-related difference. CONCLUSION: Estradiol and P antagonism affected gender-related differences of key proteins for pulmonary function and development and especially in males was associated with diminished alveolarisation.

Impact of 17beta-estradiol on cytokine-mediated apoptotic effects in primary hippocampal and neocortical cell cultures.

Estrogens are developmental regulators of mitochondrial apoptotic pathway in the central nervous system, but little is known about their involvement in cytokine-induced apoptosis. In the present study, we evaluated effects of 17beta-estradiol on pro-inflammatory cytokine- and staurosporine-mediated activation of caspase-3 and LDH-release in primary neuronal/glial cell cultures of mouse hippocampal and neocortical cells at different stages of their development in vitro. Enzyme activities were determined with colorimetric methods 6 h, 14 h, 24 h, and 48 h after exposure to the apoptotic agents. Biochemical data were supported at the cellular level by Hoechst 33342 and MAP-2 stainings, which were carried out 48 h after the treatment. Cytokines (co-treatment with Il-1beta and TNFalpha; 1 ng/ml) increased caspase-3 activity in the hippocampal and neocortical cells up to over 200% of control values, and these effects were mostly observed on 2 and 7 days in vitro (DIV). Moderate, but significant cytokine-mediated increase in LDH-release was demonstrated in both tissues, especially on 7 and 12 DIV. Estradiol (100 nM) inhibited the activation of caspase-3 at early stage of development (2 DIV) in the hippocampal, but not in the neocortical cultures. The cytokine-induced activation of caspase-3 and LDH-release was inhibited by estradiol in estrogen receptor-independent way. These data point to a possible role of estrogens as non-estrogen receptor-related inhibitors of cytokine-activated apoptotic pathway in the developing central nervous system.

Amiloride-sensitive nasal potential difference is not changed by estradiol and progesterone replacement but relates to BPD or death in a randomized trial on preterm infants.

Postnatal replacement of placental estradiol (E2) and progesterone (P) in preterm infants may improve lung function, possibly mediated through enhanced epithelial Na(+) transport and alveolar fluid clearance. Preterm infants of <29 wk gestational age and <1000 g birth weight requiring mechanical ventilation within 12 h of birth were randomized to receive either 2.5 mg/kg E2 and 22.5 mg/kg P per day (E2/P), or vehicle placebo. Epithelial Na(+) transport was assessed in 29 infants by measuring total nasal potential difference (NPD) and amiloride-sensitive NPD (ASNPD) on postnatal days of life 1, 3, 5, and 7, and mean values of all four measurements were calculated. Bronchopulmonary dysplasia (BPD) was defined as need for supplemental oxygen (goal Sa(O2) 90%) or mechanical ventilation at 36 wk corrected postmenstrual age. Mean ASNPD was -6.5 +/- 2.8 mV in infants receiving E2/P and -6.1 +/- 2.6 mV in infants receiving placebo (not significant). NPD was -10.6 +/- 3.8 mV and -10.7 +/- 3.6 mV, respectively. The ASNPD was significantly higher in infants surviving without BPD (-7.1 +/- 2.5 mV) than in infants developing BPD or not surviving (-5.2 +/- 2.4 mV). In conclusion, ASNPD is not changed by postnatal replacement of E2 and P. Infants at high risk of developing BPD had lower ASNPD values in the immediate postnatal period.

Prenatal estrogen and progesterone deprivation impairs alveolar formation and fluid clearance in newborn piglets.

Exposure to high levels of estradiol (E2) and progesterone (P) derived from the fetoplacentomaternal unit during the last trimester of pregnancy may play a crucial role in prenatal lung development and immediate postnatal alveolar fluid clearance (AFC). To measure prenatal alveolar formation and postnatal amiloride-sensitive AFC after pharmacological deprivation of E2 and P in utero, fetuses from five sows received an intramuscular depot injection of the E2 receptor blocker ICI 182.780 (ICI) and the P receptor blocker RTI 3021-022 (RTI) and fetuses of five other sows received a placebo injection (control group) during a laparotomy at 90 d of gestation (term gestation, 115 d). Piglets were delivered by cesarean section on d 114 of gestation. Of 95 live-born piglets, 35 were mechanically ventilated. The airways of the right lower lobe were isolated by a balloon catheter wedged in the bronchus and 5% albumin in 0.9% NaCl with or without 1 mmol/L amiloride was instilled. Amiloride-sensitive AFC was calculated from the protein concentration changes in fluid recovered after 120 min as the percentage of absorbed fluid. Lungs were removed under standardized conditions to perform alveolar counts. Prenatal treatment with ICI and RTI resulted in a significantly lower amiloride-sensitive AFC (median, 31%; min-max, -4-58) than placebo (74%, 18-231). Median alveolar counts per visual field were significantly lower in piglets that were exposed to ICI and RTI (38, 21-78) compared with placebo (56, 32-113). We conclude that prenatal E2 and P deprivation significantly impaired alveolar formation and amiloride-sensitive AFC.

Effects of a recombinant surfactant protein-C-based surfactant on lung function and the pulmonary surfactant system in a model of meconium aspiration syndrome.

OBJECTIVE: Meconium aspiration syndrome (MAS) remains a relevant cause of neonatal respiratory failure and is characterized by severe impairment of pulmonary gas exchange, surfactant inactivation, and pronounced inflammatory changes. Surfactant administration has been shown as an effective treatment strategy in MAS. The present study aimed at investigating the impact of a recombinant surfactant protein (SP)-C-based surfactant on pulmonary gas exchange and lung function in this model of neonatal lung injury. Furthermore, SP-B and -C were determined on the transcriptional and protein level. DESIGN: Laboratory experiment. SETTING: University laboratory. SUBJECTS: Twenty three newborn piglets (median age 6 days, weight 1900-2500 g). INTERVENTIONS: Piglets were intubated and mechanically ventilated and then received 20% sterile meconium (5 mL/kg) for induction of lung injury. After 30 mins, animals were randomized for control (n = 7, MAS controls), recombinant SP-C surfactant (n = 8), or natural surfactant (n = 8). Surfactant preparations were administered as an intratracheal bolus (75 mg/kg), and animals were ventilated for another 330 mins. Nonventilated newborn piglets at term (n = 28; median weight 1484 g, range 720-1990 g) served as a healthy reference group (healthy controls). MEASUREMENTS AND MAIN RESULTS: Lung function variables, arterial blood gas samples, and lung tissues were obtained. Expression of SP-B and -C messenger RNA was quantified in left lung lobe tissue using real-time polymerase chain reaction. Protein concentrations were determined by enzyme-linked immunosorbent assay. Scanning electron microscopy and transmission electron microscopy were performed in tissue samples of the right lung lobe. Compared with healthy controls, SP-B messenger RNA expression was significantly increased in MAS (p < .02), whereas SP-C messenger RNA expression was found to be significantly reduced (p < .001). SP concentrations, however, were not significantly different. Although a significant improvement of gas exchange and lung function was observed after surfactant administration in both groups, surfactant messenger RNA expression and protein concentrations were not significantly altered. Scanning and transmission electron microscopy showed severe pulmonary ultrastructural changes after meconium aspiration improving after surfactant treatment. CONCLUSIONS: Impairment of lung function in MAS, associated with marked changes in SP messenger RNA expression, can be sufficiently treated using recombinant SP-C-based or natural surfactant. Despite improved lung function and gas exchange as well as pulmonary ultrastructure after treatment, pulmonary SP messenger RNA expression and concentrations remained significantly affected, giving important insight into the time course following surfactant treatment in MAS.

Effect of NMDA on staurosporine-induced activation of caspase-3 and LDH release in mouse neocortical and hippocampal cells.

To achieve a better understanding of developmentally regulated NMDA- and staurosporine-induced apoptotic processes, we investigated the concerted action of these agents on caspase-3 activity and LDH release in neocortical and hippocampal cell cultures at different stages in vitro (DIV). Hoechst 33342 and MAP-2 stainings were additionally employed to visualize apoptotic changes and cell damage. The vulnerability of neocortical cells to NMDA was more prominent at later culture stages, whereas hippocampal neurons were more susceptible to NMDA treatment at earlier stages. A persistent activation of caspase-3 by staurosporine was found at all experimental stages. Despite of certain differences in susceptibility to NMDA and staurosporine, both tissues responded to regulatory action of NMDA towards staurosporine-activated caspase-3 in a similar way. Combined treatment with NMDA and staurosporine resulted in a substantial increase in caspase-3 activity in neocortical and hippocampal neurons on 2 DIV. Additive effects were also observed in neocortical cultures on 12 DIV. In contrast, NMDA substantially inhibited staurosporine-induced caspase-3 activity on 7 DIV in neocortical and hippocampal cultures. Additionally, pro-apoptotic effects of 17beta-estradiol were attenuated by NMDA on 7 DIV. Changes in vulnerability to NMDA- and staurosporine-mediated activation of caspase-3 were not strictly related to LDH release. Our data revealed that NMDA can both enhance and inhibit the staurosporine-induced neuronal cell apoptosis. The pro-apoptotic effect of NMDA was exhibited at early and late culture stages, whereas the anti-apoptotic effect was transient occurring on 7 DIV only.

Ontogenetic expression of estrogen and progesterone receptors in the mouse lung.

In the mammalian lung, estrogen and progesterone seem to be import for the morphological and functional maturation. Despite this, only sparse information is available on the onset and ontogenic expression of estrogen receptors (ER) and progesterone receptors (PR) in the perinatal lung. The expression patterns of the two known nuclear isoforms ER-alpha and ER-beta and the PR were analyzed in the pre- and postnatal lungs of BALB/c mice. Steroid receptor mRNA expression of all three receptors were highest in the prenatal lung and declined thereafter to significantly lower levels in the postnatal and adult lung. The ontogenetic pattern of ER and PR expression supports the view that both gonadal steroids are pivotal for prenatal lung maturation and development.