Long-Term Antibody Response to SARS-CoV-2 in Children.

Almost 2 years into the pandemic and with vaccination of children significantly lagging behind adults, long-term pediatric humoral immune responses to SARS-CoV-2 are understudied. The C19.CHILD Hamburg (COVID-19 Child Health Investigation of Latent Disease) Study is a prospective cohort study designed to identify and follow up children and their household contacts infected in the early 2020 first wave of SARS-CoV-2. We screened 6113 children < 18 years by nasopharyngeal swab-PCR in a low-incidence setting after general lockdown, from May 11 to June 30, 2020. A total of 4657 participants underwent antibody testing. Positive tests were followed up by repeated PCR and serological testing of all household contacts over 6 months. In total, the study identified 67 seropositive children (1.44%); the median time after infection at first presentation was 83 days post-symptom onset (PSO). Follow-up of household contacts showed less than 100% seroprevalence in most families, with higher seroprevalence in families with adult index cases compared to pediatric index cases (OR 1.79, P = 0.047). Most importantly, children showed sustained seroconversion up to 9 months PSO, and serum antibody concentrations persistently surpassed adult levels (ratio serum IgG spike children vs. adults 90 days PSO 1.75, P < 0.001; 180 days 1.38, P = 0.01; 270 days 1.54, P = 0.001). In a low-incidence setting, SARS-CoV-2 infection and humoral immune response present distinct patterns in children including higher antibody levels, and lower seroprevalence in families with pediatric index cases. Children show long-term SARS-CoV-2 antibody responses. These findings are relevant to novel variants with increased disease burden in children, as well as for the planning of age-appropriate vaccination strategies.

Phenotypic analysis of the pediatric immune response to SARS-CoV-2 by flow cytometry.

Pediatric SARS-CoV-2 infection is often mild or asymptomatic and the immune responses of children are understudied compared to adults. Here, we present and evaluate the performance of a two-panel (16- and 17 parameter) flow cytometry-based approach for immune phenotypic analysis of cryopreserved PBMC samples from children after SARS-CoV-2 infection. The panels were optimized based on previous SARS-CoV-2 related studies for the pediatric immune system. PBMC samples from seven SARS-CoV-2 seropositive children from early 2020 and five age-matched healthy controls were stained for analysis of T-cells (panel T), B and innate immune cells (panel B). Performance of the panels was evaluated in two parallel approaches, namely classical manual gating of known subpopulations and unbiased clustering using the R-based algorithm PhenoGraph. Using manual gating we clearly identified 14 predefined subpopulations of interest for panel T and 19 populations in panel B in low-volume pediatric samples. PhenoGraph found 18 clusters within the T-cell panel and 21 clusters within the innate and B-cell panel that could be unmistakably annotated. Combining the data of the two panels and analysis approaches, we found expected differentially abundant clusters in SARS-CoV-2 seropositive children compared to healthy controls, underscoring the value of these two panels for the analysis of immune response to SARS-CoV-2. We established a two-panel flow cytometry approach that can be used with limited amounts of cryopreserved pediatric samples. Our workflow allowed for a rapid, comprehensive, and robust pediatric immune phenotyping with comparable performance in manual gating and unbiased clustering. These panels may be adapted for large multi-center cohort studies to investigate the pediatric immune response to emerging virus variants in the ongoing and future pandemics.

Tricuspid valve prolapse as an early predictor for severe phenotype in children with Marfan syndrome.

AIM: In Marfan syndrome, various cardiovascular pathologies, such as aortic dilatation and mitral valve pathologies, already occur in childhood and determine course of the disease. This study aimed to establish additional cardiovascular risk markers for severe Marfan phenotypes. We investigated tricuspid valve prolapse (TVP) and its predictive value for outcome of paediatric Marfan disease. METHODS: In this retrospective, observational cohort study, we identified 130 paediatric Marfan patients (10.7 ± 4.8 years) with FBN1 variants. We divided patients into two groups based on TVP presence and performed a cross-sectional analysis to investigate the association of TVP with other cardiovascular, ocular and systemic pathologies, at first and last visit. A longitudinal analysis was performed with follow-up data. RESULTS: At baseline, patients with TVP had higher incidence of aortic root dilatation (p = 0.013), mitral valve prolapse (p = 0.0001) and systemic manifestations (p = 0.025) than patients without TVP. At follow-up, previous presence of TVP predicted higher probability of aortic root dilatation (p = 0.002), mitral valve prolapse (p = 0.0001) and systemic manifestations (p = 0.002). CONCLUSION: This shows that TVP is linked to both cardiac and extracardiac Marfan manifestations and TVP is an important marker for a disease severity in these children. Therefore, TVP should be assessed routinely using echocardiography in paediatric Marfan patients.

Next-generation sequencing of 32 genes associated with hereditary aortopathies and related disorders of connective tissue in a cohort of 199 patients.

PURPOSE: Heritable factors play an important etiologic role in connective tissue disorders (CTD) with vascular involvement, and a genetic diagnosis is getting increasingly important for gene-tailored, personalized patient management. METHODS: We analyzed 32 disease-associated genes by using targeted next-generation sequencing and exome sequencing in a clinically relevant cohort of 199 individuals. We classified and refined sequence variants according to their likelihood for pathogenicity. RESULTS: We identified 1 pathogenic variant (PV; in FBN1 or SMAD3) in 15 patients (7.5%) and ≥1 likely pathogenic variant (LPV; in COL3A1, FBN1, FBN2, LOX, MYH11, SMAD3, TGFBR1, or TGFBR2) in 19 individuals (9.6%), together resulting in 17.1% diagnostic yield. Thirteen PV/LPV were novel. Of PV/LPV-negative patients 47 (23.6%) showed ≥1 variant of uncertain significance (VUS). Twenty-five patients had concomitant variants. In-depth evaluation of reported/calculated variant classes resulted in reclassification of 19.8% of variants. CONCLUSION: Variant classification and refinement are essential for shaping mutational spectra of disease genes, thereby improving clinical sensitivity. Obligate stringent multigene analysis is a powerful tool for identifying genetic causes of clinically related CTDs. Nonetheless, the relatively high rate of PV/LPV/VUS-negative patients underscores the existence of yet unknown disease loci and/or oligogenic/polygenic inheritance.

The Pulmonary Artery in Pediatric Patients with Marfan Syndrome: An Underestimated Aspect of the Disease.

Aortic root dilatation and its complications are known to be the most important and life limiting features in patients with Marfan syndrome (MFS). Since monitoring of patients, preventive medical and surgical treatments are available nowadays, other MFS pathologies are becoming more relevant for the outcome of the disease. Main pulmonary artery (MPA) dilatation is a cardiac finding, which has not been fully investigated in children. Due to the similarities in tissue composition of the aortic and pulmonary root, MPA dilatation may cause complications and require treatment. In addition, it may be a predictor for severe connective tissue involvement. We retrospectively examined 135 pediatric patients with MFS. 8.1% showed MPA dilatation. MPA dilatation was associated with earlier occurrence of aortic dilatation, mitral valve prolapse, and systemic manifestations of MFS compared with patients without MPA dilatation (p < 0.05). The presence of MPA dilatation was also associated with a higher incidence of ectopia lentis (p < 0.05). Medical treatment was started earlier in MPA dilatation patients than in those without (p < 0.05). We conclude that MPA dilatation is a sign of more severe vascular and connective tissue involvement. Regular examination of the pulmonary artery is essential in MFS to avoid complications. As medical treatment of life threatening MFS events has improved, other features of MFS need to be investigated to improve quality of life.

Health-related quality of life is unimpaired in children and adolescents with Marfan syndrome despite its distinctive phenotype.

AIM: Marfan syndrome (MFS) is a progressive, life-threatening genetic disorder of the connective tissue, which causes impaired quality of life (QoL) in adults. This study investigated the quality of life in children and adolescents, taking into account their gender, age and how MFS affected their organs. METHODS: This prospective nonrandomised single-centre study included 46 patients with verified MFS with a mean age of 10.98 years (±3.72). QoL was measured using the self-reported, multidimensional KINDL-R questionnaire and compared with an age-matched control group of 174 children and adolescents. RESULTS: No significant overall reduction of QoL was found. Total QoL scores for patients diagnosed at four to seven years were the same as the control group (77.65 ± 9.37 versus 77.06 ± 11.72), but they were higher for patients aged eight to 16 years (75.15 ± 9.19 versus 70.46 ± 11.35, p = 0.025). No gender-specific differences or impairments in QoL during adolescence were observed (p > 0.05). Analysis of the effect of organ manifestation on QoL showed better or equal QoL scores (p > 0.05), despite distinctive phenotypes such as ectopia lentis. CONCLUSION: QoL was fairly good in paediatric patients with MFS, and there was no impairment during adolescence. Despite the distinctive phenotype, quality of life was unimpaired in younger patients.

TGFß level in healthy and children with Marfan syndrome-effective reduction under sartan therapy.

Introduction: Transforming growth factor ß (TGFß) metabolism plays an important role in the pathogenesis of Marfan syndrome (MFS). Accordingly, drug therapy uses TGFß receptor blockade to slow down the cardiovascular manifestations, above all aortic root dilatation. Angiotensin II type 1 receptor blockers (ARBs) have been shown to reduce TGFß levels in adults. Data on childhood are lacking and are now being investigated in the TiGer For Kids study presented here. Methods: We examined 125 children without chronic disease and 31 pediatric Marfan patients with a proven FBN1 variant with regard to TGFß levels. In addition, we measured TGFß levels during the initiation of ARB therapy in pediatric Marfan patients. Results: In children without chronic disease, TGFß levels were found to decrease from childhood to adolescence (p < 0.0125). We could not measure a relevantly increased TGFß level in pediatric Marfan patients. However, we showed a significant suppression of the TGFß level after treatment with ARBs (p < 0.0125) and a renewed increase shortly before the next dose. Discussion: The TGFß level in childhood changes in an age-dependent manner and decreases with age. The TGFß level drops significantly after taking ARBs. Based on our experience and data, a TGFß receptor blockade in childhood seems reasonable. So far, TGFß level cannot be used as an MFS screening biomarker.

Patient experiences of interprofessional collaboration and intersectoral communication in rare disease healthcare in Germany - a mixed-methods study.

BACKGROUND: Rare diseases are often complex, chronic and many of them life-shortening. In Germany, healthcare for rare diseases is organized in expert centers for rare diseases. Most patients additionally have regional general practicioners and specialists for basic medical care. Thus, collaboration and information exchange between sectors is highly relevant. Our study focuses on the patient and caregiver perspective on intersectoral and interdisciplinary care between local healthcare professionals (HCPs) and centers for rare diseases in Germany. The aims were (1) to investigate patients' and caregivers' general experience of healthcare, (2) to analyse patients' and caregivers' perception of collaboration and cooperation between local healthcare professionals and expert centers for rare diseases and (3) to investigate patients' and caregivers' satisfaction with healthcare in the expert centers for rare diseases. RESULTS: In total 299 individuals of whom 176 were patients and 123 were caregivers to pediatric patients participated in a survey using a questionnaire comprising several instruments and constructs. Fifty participants were additionally interviewed using a semistructured guideline. Most patients reported to receive written information about their care, have a contact person for medical issues and experienced interdisciplinary exchange within the centers for rare diseases. Patients and caregivers in our sample were mainly satisfied with the healthcare in the centers for rare diseases. The qualitative interviews showed a rather mixed picture including experiences of uncoordinated care, low engagement and communication difficulties between professionals of different sectors. Patients reported several factors that influenced the organization and quality of healthcare e.g. engagement and health literacy in patients or engagement of HCPs. CONCLUSIONS: Our findings indicate the high relevance of transferring affected patients to specialized care as fast as possible to provide best medical treatment and increase patient satisfaction. Intersectoral collaboration should exceed written information exchange and should unburden patients of being and feeling responsible for communication between sectors and specialists. Results indicate a lack of inclusion of psychosocial aspects in routine care, which suggests opportunities for necessary improvements.

The Kid-Short Marfan Score (Kid-SMS) - an easy executable risk score for suspected paediatric patients with Marfan syndrome.

AIM: Due to age-dependent manifestations, diagnosis of Marfan syndrome (MFS) in children and adolescents is sophisticated. Although revised Ghent criteria is a major step forward, its utility in children is still restricted due to expensive and technically advanced diagnostics. As early diagnosis submits long-term benefits concerning prognosis, the need of an appropriate diagnostic tool for risk stratification of suspected paediatric patients with Marfan is justified. METHODS AND RESULTS: Sixty paediatric patients with Marfan were subject to a standardized diagnostic programme. All clinical symptoms of the revised Ghent nosology were analysed concerning age at first clinical manifestation, prevalence and likelihood ratio for MFS. Symptoms with early onset, high prevalence and high positive likelihood ratio were identified and combined for a risk score called Kid-Short Marfan Score (Kid-SMS). Three risk categories for suspicion of Marfan syndrome were developed. Finally, the Kid-SMS was operated in 130 paediatric patients with suspected MFS. Kid-SMS identified significantly more suspected patients with Marfan compared with Ghent nosology, revised Ghent and genetics alone without oversensitivity. CONCLUSION: Whereas diagnosis of MFS in childhood is sophisticated, Kid-SMS is a useful tool for risk stratification of suspected paediatric patients with Marfan by easy executable diagnostics, especially for paediatricians and paediatric cardiologists.

Impact of age and gender on cardiac pathology in children and adolescents with Marfan syndrome.

Cardiac pathologies are the major aspect in the treatment strategies for Marfan syndrome (MFS). In this progressive disease, less is known about manifestations and progression of cardiovascular symptoms in children. To define a certain decision regarding therapeutic options, knowledge concerning the onset of cardiovascular findings is essential. From 1998 to 2011, suspected pediatric Marfan patients were subjected to a standardized diagnostic program. Cardiovascular findings were analyzed in terms of age at first clinical manifestation, prevalence and gender differences, morbidity, mortality, and treatment. Marfan syndrome was diagnosed in 82 patients (46 boys; mean age at diagnosis, 9.0 ± 5.7 years). At first presentation, aortic root dilation was found in 56 % of patients, mitral valve prolapse in 31 %, whereas pulmonary artery dilation was detected in 22 % and tricuspid valve prolapse in only 17 % of patients. Aortic (2.5 %) and mitral valve regurgitations (22 %) are significantly correlated with aortic root dilation (p < 0.01) and mitral valve prolapse (p < 0.05) but without relevant progression during childhood. Prophylactic medication was initiated for 42 % of the patients (mean age, 8.0 ± 4.5 years) because of progressive aortic root dilation. Aortic dissection did not appear. Aortic root surgery was needed for 4 % of the patients. Gender-specific differences in cardiovascular findings, progression of disease, or treatment did not appear. Comparable with adults, aortic root dilation is the most frequent cardiovascular finding in children and associated with relevant morbidity, whereas aortic and mitral valve regurgitation are of minor clinical relevance. Manifestation at an early age and slow progression of cardiovascular findings underscore the necessity of repeated echocardiographic examinations for early diagnosis and start of prophylactic treatment.

Health-related quality of life compared with cardiopulmonary exercise testing at the midterm follow-up visit after tetralogy of Fallot repair: a study of the German competence network for congenital heart defects.

This nationwide study aimed to evaluate health-related quality of life (QoL) experienced by children after tetralogy of Fallot repair and to compare self-reported physical ability with objective exercise performance. This prospective nonrandomized, government-funded multicenter study enrolled 168 patients (70 girls; ages 8-16 years) after tetralogy of Fallot repair at eight German heart centers. Health-related QoL was analyzed by the self-reported KINDL-R quality-of-life questionnaire. The patients' actual exercise capacity was evaluated by a cardiopulmonary exercise test. Health-related QoL and cardiopulmonary exercise capacity were compared with those of an age-matched German standard population. Correlation of health-related QoL with self-estimated physical rating and cardiopulmonary exercise capacity were analyzed. Health-related QoL in children and adolescents after tetralogy of Fallot repair is without limitation. Compared with the standard population, all the items evaluated by the KINDL-R questionnaire showed better or similar values, whereas objective exercise capacity compared with that of the standard population was impaired. Peak oxygen uptake correlated significantly with the physical well-being (p = 0.002) and the total score (p = 0.01) of the KINDL-R questionnaire. Health-related QoL experienced by children and adolescents after tetralogy of Fallot repair is comparable with that of the healthy standard population. However, closer inspection shows that self-estimated physical functioning is significantly overestimated compared with actual exercise capacity. Quality-of-life instruments and exercise tests, therefore, should be used in a complementary manner with children to avoid eventually fatal misinterpretation of patient-estimated physical ability.

Value of amino-terminal pro B-natriuretic peptide in diagnosing Kawasaki disease.

BACKGROUND: The aim of the present study was to investigate the diagnostic value of the N-terminal B-type natriuretic peptide (NT-proBNP) in acute Kawasaki disease (KD) given that the clinical criteria and the current basic laboratory tests lack the necessary specificity for accurate diagnosis. METHODS: Basic biological tests and serum NT-proBNP levels obtained from acute KD patients were compared to that of febrile controls. NT-proBNP was considered abnormal based on the following definitions: above a cut-off determined on receiver operator characteristic (ROC) analysis, above the upper limit for age, or above 2 SD calculated from healthy children. Analyses were also performed for KD cases with complete or incomplete criteria combined and separately. RESULTS: There were 81 patients and 49 controls aged 3.60 ± 2.77 versus 4.25 ± 3.88 years (P= 0.69). ROC analysis yielded significant area under the curve for NT-proBNP. The sensitivity, specificity, positive and negative predictive values were 70.4-88.9%, 69.4-91.8%, 82.8-93.4%, and 65.2-79.1%. The odds ratios based on NT-proBNP definitions varied between 18.13 (95% confidence interval [CI]: 7.21-45.57), 20.82 (95%CI: 8.18-53.0), and 26.71 (95%CI: 8.64-82.57; P < 0.001). Results were reproducible for cases with complete or incomplete criteria separately. CONCLUSION: NT-proBNP is a reliable marker for the diagnosis of KD. Prospective clinical studies with emphasis on NT-proBNP in a diagnostic algorithm are needed.

Expanding the clinical spectrum of COL2A1 related disorders by a mass like phenotype.

MASS phenotype is a connective tissue disorder clinically overlapping with Marfan syndrome and caused by pathogenic variants in FBN1. We report four patients from three families presenting with a MASS-like phenotype consisting of tall stature, arachnodactyly, spinal deformations, dural ectasia, pectus and/or feet deformations, osteoarthritis, and/or high arched palate. Gene panel sequencing was negative for FBN1 variants. However, it revealed likely pathogenic missense variants in three individuals [c.3936G > T p.(Lys1312Asn), c.193G > A p.(Asp65Asn)] and a missense variant of unknown significance in the fourth patient [c.4013G > A p.(Ser1338Asn)] in propeptide coding regions of COL2A1. Pathogenic COL2A1 variants are associated with type II collagenopathies comprising a remarkable clinical variablility. Main features include skeletal dysplasia, ocular anomalies, and auditory defects. A MASS-like phenotype has not been associated with COL2A1 variants before. Thus, the identification of likely pathogenic COL2A1 variants in our patients expands the phenotypic spectrum of type II collagenopathies and suggests that a MASS-like phenotype can be assigned to various hereditary disorders of connective tissue. We compare the phenotypes of our patients with related disorders of connective tissue and discuss possible pathomechanisms and genotype-phenotype correlations for the identified COL2A1 variants. Our data recommend COL2A1 sequencing in FBN1-negative patients suggestive for MASS/Marfan-like phenotype (without aortopathy).

Specific CD4+ T Cell Responses to Ancestral SARS-CoV-2 in Children Increase With Age and Show Cross-Reactivity to Beta Variant.

SARS-CoV-2 is still a major burden for global health despite effective vaccines. With the reduction of social distancing measures, infection rates are increasing in children, while data on the pediatric immune response to SARS-CoV-2 infection is still lacking. Although the typical disease course in children has been mild, emerging variants may present new challenges in this age group. Peripheral blood mononuclear cells (PBMC) from 51 convalescent children, 24 seronegative siblings from early 2020, and 51 unexposed controls were stimulated with SARS-CoV-2-derived peptide MegaPools from the ancestral and beta variants. Flow cytometric determination of activation-induced markers and secreted cytokines were used to quantify the CD4+ T cell response. The average time after infection was over 80 days. CD4+ T cell responses were detected in 61% of convalescent children and were markedly reduced in preschool children. Cross-reactive T cells for the SARS-CoV-2 beta variant were identified in 45% of cases after infection with an ancestral SARS-CoV-2 variant. The CD4+ T cell response was accompanied most predominantly by IFN-γ and Granzyme B secretion. An antiviral CD4+ T cell response was present in children after ancestral SARS-CoV-2 infection, which was reduced in the youngest age group. We detected significant cross-reactivity of CD4+ T cell responses to the more recently evolved immune-escaping beta variant. Our findings have epidemiologic relevance for children regarding novel viral variants of concern and vaccination efforts.

Genotype-Phenotype Correlation in Children: The Impact of FBN1 Variants on Pediatric Marfan Care.

Currently, no reliable genotype-phenotype correlation is available for pediatric Marfan patients in everyday clinical practice. We investigated correlations of FBN1 variants with the prevalence and age of onset of Marfan manifestations in childhood and differentiated three groups: missense/in-frame, splice, and nonsense/frameshift variants. In addition, we differentiated missense variants destroying or generating a cysteine (cys-missense) and alterations not affecting cysteine. We categorized 105 FBN1-positive pediatric patients. Patients with cys-missense more frequently developed aortic dilatation (p = 0.03) requiring medication (p = 0.003), tricuspid valve prolapse (p = 0.03), and earlier onset of myopia (p = 0.02) than those with other missense variants. Missense variants correlated with a higher prevalence of ectopia lentis (p = 0.002) and earlier onset of pulmonary artery dilatation (p = 0.03) than nonsense/frameshift, and dural ectasia was more common in the latter (p = 0.005). Pectus excavatum (p = 0.007) appeared more often in patients with splice compared with missense/in-frame variants, while hernia (p = 0.04) appeared earlier in the latter. Findings on genotype-phenotype correlations in Marfan-affected children can improve interdisciplinary therapy. In patients with cys-missense variants, early medical treatment of aortic dilatation seems reasonable and early regular ophthalmologic follow-up essential. Patients with nonsense/frameshift and splice variants require early involvement of orthopedic specialists to support the growing child.

Marfan Syndrome Versus Bicuspid Aortic Valve Disease: Comparative Analysis of Obstetric Outcome and Pregnancy-Associated Immediate and Long-Term Aortic Complications.

Pregnancy poses a threat to women with aortopathy. Conclusive data on the obstetric and aortic outcome in this risk collective, especially when it comes to aortic complications in the long term, are still missing. This study offers a comparative analysis of pregnancy-associated outcome in 113 consecutive women with Marfan syndrome or bicuspid aortic valve disease, including 46 ever-pregnant and 37 never-pregnant women with Marfan syndrome, and 23 ever-pregnant and 7 never-pregnant females with bicuspid aortic valve disease. The overall obstetric outcome was comparable between ever-pregnant women with Marfan syndrome and with bicuspid aortic valve disease (p = 0.112). Pregnancy-associated aortic dissection occurred in two women with Marfan syndrome (3%) during a total of 62 completed pregnancies, whereas no single case of aortic event occurred in women with bicuspid aortic valve disease during a total of 36 completed pregnancies (p = 0.530). In the long-term follow-up, aortic dissection occurred in 21% of ever-pregnant women with Marfan syndrome, but in none of the women with bicuspid aortic valve disease (p = 0.022). Proximal aortic surgery was performed with similar frequency in ever-pregnant women with Marfan syndrome and with bicuspid aortic valve disease in the long term (p = 0.252). However, ever-pregnant women with Marfan syndrome were younger when surgery was performed (44 ± 9 vs. 59 ± 7 years; p = 0.041). In Marfan syndrome, long-term growth of the aorta was comparable between ever-pregnant and never-pregnant women. Pregnancy thus exhibited an increased immediate aortic risk only in women with Marfan syndrome, but not in women with bicuspid aortic valve disease. Previous pregnancy did not relate to an increased long-term risk of adverse aortic events in women with Marfan syndrome or with bicuspid aortic valve disease.

Cardiovascular Biomarkers in Amniotic Fluid, Umbilical Arterial Blood, Umbilical Venous Blood, and Maternal Blood at Delivery, and Their Reference Values for Full-Term, Singleton, Cesarean Deliveries.

Background: Several cardiovascular biomarkers have regulatory functions in perinatal physiology. Aim: This study aimed to analyze the feto-maternal distribution pattern of biomarkers in samples of amniotic fluid, umbilical arterial blood, umbilical venous blood, and maternal blood samples, and to establish reference values. Each linked sample set consisted of the combined samples obtained in an individual pregnancy. Study design: We performed a prospective, observational, cross-sectional, single-center study. Subjects: The sample cohort included 189 neonates who were born to 170 mothers. A total of 162/189 neonates were full term and 129/189 were delivered by elective cesarean section. Outcome measures: Midregional pro-adrenomedullin (MRproADM [nmol/L]), midregional pro-atrial natriuretic peptide (MRproANP [pmol/L]), brain natriuretic peptide (BNP [pg/mL]), N-terminal pro-brain natriuretic peptide (NTproBNP [pg/mL]), copeptin [pmol/L], and high-sensitive troponin I (hsTnI [pg/mL]) levels were measured. Results: In singleton, full-term, primary cesarean deliveries (n = 91), biomarker levels (median, [IQR]) at delivery were as follows. MRproADM levels in umbilical arterial blood/umbilical venous blood/amniotic fluid/maternal blood were 0.88 (0.20)/0.95 (0.18)/2.80 (1.18)/1.10 (0.54), respectively. MRproANP levels were 214.23 (91.38)/216.03 (86.15)/0.00 (3.82)/50.67 (26.81), respectively. BNP levels were 14.60 (25.18)/22.08 (18.91)/7.15 (6.01)/6.20 (18.23), respectively. NTproBNP levels were 765.48 (555.24)/816.45 (675.71)/72.03 (55.58)/44.40 (43.94), respectively. Copeptin levels were 46.17 (290.42)/5.54 (9.08)/9.97 (7.44)/4.61 (4.59), respectively. Levels of hsTnI were 6.20 (4.25)/5.60 (5.01)/0.45 (1.73)/2.50 (2.40), respectively. Conclusion: We determined reference values for biomarkers in term neonates delivered by primary cesarean section in amniotic fluid, umbilical arterial and venous blood, and maternal blood. Biomarkers in the fetal circulation appear to be of primary fetal origin, except for MRproADM.

Case-matched Comparison of Cardiovascular Outcome in Loeys-Dietz Syndrome versus Marfan Syndrome.

Background: Pathogenic variants in TGFBR1, TGFBR2 and SMAD3 genes cause Loeys-Dietz syndrome, and pathogenic variants in FBN1 cause Marfan syndrome. Despite their similar phenotypes, both syndromes may have different cardiovascular outcomes. Methods: Three expert centers performed a case-matched comparison of cardiovascular outcomes. The Loeys-Dietz group comprised 43 men and 40 women with a mean age of 34 ± 18 years. Twenty-six individuals had pathogenic variants in TGFBR1, 40 in TGFBR2, and 17 in SMAD3. For case-matched comparison we used 83 age and sex-frequency matched individuals with Marfan syndrome. Results: In Loeys-Dietz compared to Marfan syndrome, a patent ductus arteriosus (p = 0.014) was more prevalent, the craniofacial score was higher (p < 0.001), the systemic score lower (p < 0.001), and mitral valve prolapse less frequent (p = 0.003). Mean survival for Loeys-Dietz and Marfan syndrome was similar (75 ± 3 versus 73 ± 2 years; p = 0.811). Cardiovascular outcome was comparable between Loeys-Dietz and Marfan syndrome, including mean freedom from proximal aortic surgery (53 ± 4 versus 48 ± 3 years; p = 0.589), distal aortic repair (72 ± 3 versus 67 ± 2 years; p = 0.777), mitral valve surgery (75 ± 4 versus 65 ± 3 years; p = 0.108), and reintervention (20 ± 3 versus 14 ± 2 years; p = 0.112). In Loeys-Dietz syndrome, lower age at initial presentation predicted proximal aortic surgery (HR = 0.748; p < 0.001), where receiver operating characteristic analysis identified ≤33.5 years with increased risk. In addition, increased aortic sinus diameters (HR = 6.502; p = 0.001), and higher systemic score points at least marginally (HR = 1.175; p = 0.065) related to proximal aortic surgery in Loeys-Dietz syndrome. Conclusions: Cardiovascular outcome of Loeys-Dietz syndrome was comparable to Marfan syndrome, but the severity of systemic manifestations was a predictor of proximal aortic surgery.

The spectrum of syndromes and manifestations in individuals screened for suspected Marfan syndrome.

The diagnosis of Marfan syndrome (MFS) is based on evaluating a large number of clinical criteria. We have observed that many persons presenting in specialized centers for "Marfan-like" features do not have MFS, but exhibit a large spectrum of other syndromes. The spectrum of these syndromes and the distribution of "Marfan-like" features remain to be characterized. Thus, we prospectively evaluated 279 consecutive patients with suspected MFS (144 men and 135 women at a mean age of 34+/-13 years) for presence of 27 clinical criteria considered characteristic of MFS. The most frequent reasons to refer individuals for suspected MFS were skeletal features (31%), a family history of MFS, or aortic complications (29%), aortic dissection or aneurysm (19%), and eye manifestations (9%). Using established criteria, we confirmed MFS in 138 individuals (group 1) and diagnosed other connective tissue diseases, both with vascular involvement in 30 (group 2) and without vascular involvement in 39 (group 3), and excluded any distinct disease in 72 individuals (group 4). Clinical manifestations of MFS were present in all four patient groups and there was no single clinical criterion that exhibited positive and negative likelihood ratios that were per se sufficient to confirm or rule out MFS. We conclude that "Marfan-like" features are not exclusively indicative of MFS but also of numerous, alternative inherited diseases with many of them carrying a hitherto poorly defined cardiovascular risk. These alternative diseases require future study to characterize their responses to therapy and long-term prognosis.

Population pharmacokinetics and dose simulation of carvedilol in paediatric patients with congestive heart failure.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: * Applying in silico tools such as population pharmacokinetic analysis and simulation will help to find adequate dosing strategies and increase the probability of success for a randomized controlled trial. * Up to now, for carvedilol in paediatric patients with congestive heart failure (CHF) the dose has been linearly extrapolated from adults, but the results with this dosing strategy are ambiguous. * Further trials are necessary to establish carvedilol for paediatric patients with CHF. WHAT THIS STUDY ADDS: * Carvedilol pharmacokinetics in paediatric patients with CHF depends on the weight and age of the patient. * Therefore, the drug exposure differs substantially between patients of different ages receiving the same dose with respect to body weight. * Simulations revealed that an age-adjusted carvedilol dosing strategy with higher doses for younger patients with respect to body weight is preferable to a uniform one. AIMS: To investigate the ontogeny of carvedilol pharmacokinetics and to develop an age-appropriate carvedilol dosing strategy for paediatric patients. METHODS: Data were derived from a prospective, nonplacebo-controlled study of carvedilol for the treatment of paediatric patients with congestive heart failure and analysed using a nonlinear mixed-effects modelling approach (NONMEM, Version V 1.1). The population pharmacokinetic model was further utilized for simulations of different carvedilol dosing strategies. RESULTS: Four hundred and eighty carvedilol plasma concentrations of 41 patients (0.1-19.3 years; median 3.5) were included in the analysis. A two-compartment model with first-order absorption and absorption lag served as structural model. Weight and age were the most important covariates for carvedilol pharmacokinetics. The weight-adjusted clearance was highest for the younger patients with 2.7 l h(-1) kg(-1) for a 1-year-old patient compared with 0.7 l h(-1) kg(-1) for a 19.3-year-old patient. Dose simulations revealed that the area under the plasma concentration-time curve (AUC) as a measure of drug exposure increased with age despite constant doses with respect to body weight. For infants (28 days to 23 months), children (2-11 years) and adolescents (12-15 years) daily doses of 3, 2 and 1 mg kg(-1), administered in two or three discrete doses, were necessary to reach an exposure comparable to adults receiving 0.7 mg kg(-1) day(-1). CONCLUSION: The ontogeny of carvedilol pharmacokinetics in paediatric patients depends on age and weight. Dose simulations revealed that younger patients have to be treated with higher doses with respect to body weight to reach the same exposure as adults.