Publications

Abstract

Background: SARS-CoV-2 can lead to several types of complications during pregnancy. Variant surges are associated with different severities of disease. Few studies have compared the clinical consequences of specific variants on obstetrical and neonatal outcomes. Our goal was to evaluate and compare disease severity in pregnant women and obstetrical or neonatal complications between variants of SARS-CoV-2 that have circulated in France over a two-year period (2020-2022).

Method: This retrospective cohort study included all pregnant women with a confirmed SARS-CoV-2 infection (positive naso-pharyngeal RT-PCR test) from March 12, 2020 to January 31, 2022, in three tertiary maternal referral obstetric units in the Paris metropolitan area, France. We collected clinical and laboratory data for mothers and newborns from patients’ medical records. Variant identification was either available following sequencing or extrapolated from epidemiological data.

Results: There were 234/501 (47%) Wild Type (WT), 127/501 (25%) Alpha, 98/501 (20%) Delta, and 42/501 (8%) Omicron. No significative difference was found regarding two composite adverse outcomes. There were significantly more hospitalizations for severe pneumopathy in Delta variant than WT, Alpha and Omicron respectively (63% vs 26%, 35% and 6%, p<0.001), more frequent oxygen administration (23% vs 12%, 10% and 5%, p = 0,001) and more symptomatic patients at the time of testing with Delta and WT (75% and 71%) versus Alpha and Omicron variants (55% and 66% respectively, p<0.01). Stillbirth tended to be associated with variants (p = 0.06): WT 1/231 (<1%) vs 4/126 (3%), 3/94 (3%), and 1/35 (3%) in Alpha, Delta and Omicron cases respectively. No other difference was found.

Conclusion: Although the Delta variant was associated with more severe disease in pregnant women, we found no difference regarding neonatal and obstetrical outcomes. Neonatal and obstetrical specific severity may be due to mechanisms other than maternal ventilatory and general infection

Abstract

Aim: To assess the predictive validity of parent-reported gross motor impairment (GMI) at age 2 years to detect significant movement difficulties at age 5 years in children born extremely preterm.

Method: Data were from 556 children (270 males, 286 females) born at less than 28 weeks’ gestation in 2011 to 2012 in 10 European countries. Parent report of moderate/severe GMI was defined as walking unsteadily or unable to walk unassisted at 2 years corrected age. Examiners assessed significant movement difficulties (score ≤ 5th centile on the Movement Assessment Battery for Children, Second Edition) and diagnoses of cerebral palsy (CP) were collected by parent report at 5 years chronological age.

Results: At 2 years, 66 (11.9%) children had moderate/severe GMI. At 5 years, 212 (38.1%) had significant movement difficulties. Parent reports of GMI at age 2 years accurately classified CP at age 5 years in 91.0% to 93.2% of children. Classification of moderate/severe GMI at age 2 years had high specificity (96.2%; 95% confidence interval 93.6-98.0) and positive predictive value (80.3%; 68.7-89.1) for significant movement difficulties at age 5 years. However, 74.5% of children with significant movement difficulties at 5 years were not identified with moderate/severe GMI at age 2 years, resulting in low sensitivity (25.1%; 19.4-31.5).

Interpretation: This questionnaire may be used to identify children born extremely preterm who at age 2 years have a diagnosis of CP or movement difficulties that are likely to have a significant impact on their functional outcomes at age 5 years.

ABSTRACT

Bacterial colonization in the gut plays a pivotal role in neonatal necrotizing enterocolitis (NEC) development, but the relationship between bacteria and NEC remains unclear. In this study, we aimed to elucidate whether bacterial butyrate end-fermentation metabolites participate in the development of NEC lesions and confirm the enteropathogenicity of Clostridium butyricum and Clostridium neonatale in NEC. First, we produced C.butyricum and C.neonatale strains impaired in butyrate production by genetically inactivating the hbd gene encoding β-hydroxybutyryl-CoA dehydrogenase that produces end-fermentation metabolites. Second, we evaluated the enteropathogenicty of the hbd-knockout strains in a gnotobiotic quail model of NEC. The analyses showed that animals harboring these strains had significantly fewer and less intense intestinal lesions than those harboring the respective wild-type strains. In the absence of specific biological markers of NEC, the data provide original and new mechanistic insights into the disease pathophysiology, a necessary step for developing potential novel therapies.

Abstract

In this study, we attempted to find genetic variants affecting gene expression (eQTL = expression Quantitative Trait Loci) in the human placenta in normal and pathological situations. The analysis of gene expression in placental diseases (Pre-eclampsia and Intra-Uterine Growth Restriction) is hindered by the fact that diseased placental tissue samples are generally taken at earlier gestations compared to control samples. The difference in gestational age is considered a major confounding factor in the transcriptome regulation of the placenta. To alleviate this significant problem, we propose here a novel approach to pinpoint disease-specific cis-eQTLs. By statistical correction for gestational age at sampling as well as other confounding/surrogate variables systematically searched and identified, we found 43 e-genes for which proximal SNPs influence expression level. Then, we performed the analysis again, removing the disease status from the covariates, and we identified 54 e-genes, 16 of which are identified de novo and, thus, possibly related to placental disease. We found a highly significant overlap with previous studies for the list of 43 e-genes, validating our methodology and findings. Among the 16 disease-specific e-genes, several are intrinsic to trophoblast biology and, therefore, constitute novel targets of interest to better characterize placental pathology and its varied clinical consequences. The approach that we used may also be applied to the study of other human diseases where confounding factors have hampered a better understanding of the pathology.

Abstract

Background: Cerebral malaria (CM) is a neuropathology which remains one of the deadliest forms of malaria among African children. The kinetics of the pathophysiological mechanisms leading to neuroinflammation and the death or survival of patients during CM are still poorly understood. The increasing production of cytokines, chemokines and other actors of the inflammatory and oxidative response by various local actors in response to neuroinflammation plays a major role during CM, participating in both the amplification of the neuroinflammation phenomenon and its resolution. In this study, we aimed to identify risk factors for CM death among specific variables of inflammatory and oxidative responses to improve our understanding of CM pathogenesis.

Methods: Children presenting with CM (n = 70) due to P. falciparum infection were included in southern Benin and divided according to the clinical outcome into 50 children who survived and 20 who died. Clinical examination was complemented by fundoscopic examination and extensive blood biochemical analysis associated with molecular diagnosis by multiplex PCR targeting 14 pathogens in the patients’ cerebrospinal fluid to rule out coinfections. Luminex technology and enzyme immunoassay kits were used to measure 17 plasma and 7 urinary biomarker levels, respectively. Data were analysed by univariate analysis using the nonparametric Mann‒Whitney U test and Pearson’s Chi2 test. Adjusted and multivariate analyses were conducted separately for plasma and urinary biomarkers to identify CM mortality risk factors.

Results: Univariate analysis revealed higher plasma levels of tumour necrosis factor (TNF), interleukin-1beta (IL-1β), IL-10, IL-8, C-X-C motif chemokine ligand 9 (CXCL9), granzyme B, and angiopoietin-2 and lower urinary levels of prostanglandine E2 metabolite (PGEM) in children who died compared to those who survived CM (Mann-Whitney U-test, P-values between 0.03 and < 0.0001). The multivariate logistic analysis highlighted elevated plasma levels of IL-8 as the main risk factor for death during CM (adjusted odd ratio = 14.2, P-value = 0.002). Values obtained during follow-up at D3 and D30 revealed immune factors associated with disease resolution, including plasma CXCL5, C-C motif chemokine ligand 17 (CCL17), CCL22, and urinary 15-F2t-isoprostane.

Conclusions: The main risk factor of death during CM was thus elevated plasma levels of IL-8 at inclusion. Follow-up of patients until D30 revealed marker profiles of disease aggravation and resolution for markers implicated in neutrophil activation, endothelium activation and damage, inflammatory and oxidative response. These results provide important insight into our understanding of CM pathogenesis and clinical outcome and may have important therapeutic implications.

Abstract

Early treatment of neonatal diabetes with sulfonylureas has been proven to produce marked improvements of neurodevelopment, beside the demonstrated efficacy on glycemic control. Several barriers still prevent an early treatment in preterm babies including the limited availability of suitable galenic form of glibenclamide. We adopted oral glibenclamide suspension (Amglidia) for the early treatment of neonatal diabetes due to an homozygous variant of KCNJ11 gene c.10C>T [p.Arg4Cys] in an extremely preterm infant born at 26 + 2 weeks’ of gestational age. After ~6 weeks of insulin treatment with a low glucose intake (4.5 g/kg/day), the infant was switched to Amglidia 6 mg/ml diluted in maternal milk, via nasogastric tube (0.2 mg/kg/day) progressively reduced to 0.01 mg/kg/day (after ~3 months). While on glibenclamide, the patient exhibited a mean daily growth of 11 g/kg/day. The treatment was suspended at month 6 of birth (weight 4.9 kg [5th-10th centile], M3 of c.a.) for normalization of glucose profile. During the treatment, the patient exhibited a stable glucose profile within the range of 4-8 mmol/L in the absence of hypo or hyperglycemic episodes with 2-3 blood glucose tests per day. The patient was diagnosed with retinopathy of prematurity Stade II in Zone II without plus disease at 32 weeks, with progressive regression and complete retinal vascularization at 6 months of birth. Amglidia could be regarded as the specific treatment for neonatal diabetes even in preterm babies due to its beneficial effect on the metabolic and neurodevelopmental side.

Abstract

Background: Worldwide, Escherichia coli is the leading cause of neonatal Gram-negative bacterial meningitis, but full understanding of the pathogenesis of this disease is not yet achieved. Moreover, to date, no vaccine is available against bacterial neonatal meningitis.

Methods: Here, we used Transposon Sequencing of saturated banks of mutants (TnSeq) to evaluate E. coli K1 genetic fitness in murine neonatal meningitis. We identified E. coli K1 genes encoding for factors important for systemic dissemination and brain infection, and focused on products with a likely outer-membrane or extra-cellular localization, as these are potential vaccine candidates. We used in vitro and in vivo models to study the efficacy of active and passive immunization.

Results: We selected for further study the conserved surface polysaccharide Poly-β-(1-6)-N-Acetyl Glucosamine (PNAG), as a strong candidate for vaccine development. We found that PNAG was a virulence factor in our animal model. We showed that both passive and active immunization successfully prevented and/or treated meningitis caused by E. coli K1 in neonatal mice. We found an excellent opsonophagocytic killing activity of the antibodies to PNAG and in vitro these antibodies were also able to decrease binding, invasion and crossing of E. coli K1 through two blood brain barrier cell lines. Finally, to reinforce the potential of PNAG as a vaccine candidate in bacterial neonatal meningitis, we demonstrated that Group B Streptococcus, the main cause of neonatal meningitis in developed countries, also produced PNAG and that antibodies to PNAG could protect in vitro and in vivo against this major neonatal pathogen.

Interpretation: Altogether, these results indicate the utility of a high-throughput DNA sequencing method to identify potential immunotherapy targets for a pathogen, including in this study a potential broad-spectrum target for prevention of neonatal bacterial infections.

Abstract

Background: Motor impairment is common after extremely preterm (EPT, <28 weeks’ gestational age (GA)) birth, with cerebral palsy (CP) affecting about 10% of children and non-CP movement difficulties (MD) up to 50%. This study investigated the sociodemographic, perinatal and neonatal risk factors for CP and non-CP MD.

Methods: Data come from a European population-based cohort of children born EPT in 2011-2012 in 11 countries. We used multinomial logistic regression to assess risk factors for CP and non-CP MD (Movement Assessment Battery for Children – 2nd edition ≤5th percentile) compared to no MD (>15th percentile) among 5-year-old children.

Results: Compared to children without MD (n = 366), young maternal age, male sex and bronchopulmonary dysplasia were similarly associated with CP (n = 100) and non-CP MD (n = 224) with relative risk ratios (RRR) ranging from 2.3 to 3.6. CP was strongly related to severe brain lesions (RRR >10), other neonatal morbidities, congenital anomalies and low Apgar score (RRR: 2.4-3.3), while non-CP MD was associated with primiparity, maternal education, small for GA (RRR: 1.6-2.6) and severe brain lesions, but at a much lower order of magnitude.

Conclusion: CP and non-CP MD have different risk factor profiles, with fewer clinical but more sociodemographic risk factors for non-CP MD.

Impact: Young maternal age, male sex and bronchopulmonary dysplasia similarly increased risks of both cerebral palsy and non-cerebral palsy movement difficulties. Cerebral palsy was strongly related to clinical risk factors including severe brain lesions and other neonatal morbidities, while non-cerebral palsy movement difficulties were more associated with sociodemographic risk factors. These results on the similarities and differences in risk profiles of children with cerebral palsy and non-cerebral palsy movement difficulties raise questions for etiological research and provide a basis for improving the identification of children who may benefit from follow-up and early intervention.

Abstract

In order to inform patients undergoing ART regarding their chances for motherhood, it seems useful to describe « freeze all » outcomes according to the different potential indications. The goal of this study was to examine the impact of a « freeze-all approach » on the cumulative live birth rate (cLBR) according to the indication. It is a cohort study including women who had undergone ovarian stimulation (OS) using an antagonist protocol with GnRH agonist triggering between 09.2016 and 09.2018 followed by a freeze-all cycle of blastocyst embryos. The ART outcomes were compared between the two main indications of the freeze-all strategy which were in our cohort: risk of ovarian hyperstimulation syndrome (OHSS) and endometriosis. The ART outcomes were also described for the others indications (inadequate endometrium and/or premature progesterone elevation at trigger day, two or more previous ART failures, and autoimmune disease and/or a high risk of thromboembolic disease (AI and/or TE risk)). In total, 658 women were included. The cLBR in the total population was 37.7% (248/658). The cLBR was significantly higher in the « OHSS risk » group (133/281, 47.3%) than in the « endometriosis » group (69/190, 36.3%) (p = 0.017). No significant differences were noted regarding perinatal outcomes, except a significantly higher risk of placenta praevia (PP) observed in the « endometriosis » group (10.1%) (p = 0.002). The « freeze-all approach » yielded good results in terms of the cLBR and especially in case of OHSS risk. These data should be taken into account when informing patients about the ART strategy and their chances of motherhood.

Abstract

Introduction: Embryo transfer(ET) is one of the main procedures to become pregnant by assisted reproductive technology(ART). Simulation training is a way to improve the skills of clinicians. The objective of this study was to evaluate the interest of trainees in learning embryo transfer using simulators.

Material and methods: An observational study was conducted at the University hospital-based research center. Trainees, comprising midwives and resident or graduated gynecologists, who attended the medical training for infertility and ART in June 2019, were included. They trained on two ET simulators (Simulator A and B) and complete an anonymously online questionnaire. A sub-group analysis focusing on graduated gynecologists not performing ET in current practice, was performed.

Results: Thirty-two trainees were included. Trainees felt that ET simulators should be used in medical education to promote learning how to perform the ET procedure (n=26, 81.3% for Simulator A and n=21, 65.5% for Simulator B; p=0.31). The use of both simulators improved the level of self-confidence (81.3% and 75.0% respectively; p=0.55). Significant differences in the global and in the subgroup analysis (n=24) in favor of Simulator A were observed regarding learning the precision of the ET procedure (p<0.01), the pathway to introduce the catheter into the uterine cavity (p<0.05), and the guidance for proper placement of the catheter into the uterine cavity (p=0.03). In the subgroup analysis of graduated gynecologists not performing ET in current practice, Simulator A was found more realistic for the visualization of the introduction of the catheter into the uterine cavity (p=0.01) and more useful to learn about difficult cases (p=0.03).

Conclusion: Students expressed a high level of interest in ET simulators to improve their skills. Although the simulators displayed some differences regarding learning the precision of the ET procedure, both improved the level of self-confidence. This new learning method needs to be further developed in order to offer to trainees the most realistic simulators.

Trial registration: This study was approved for publication by the Ethics Review Committee of the Cochin University Hospital (CLEP) (n° AAA-2020-08016) retrospectively registered.