The Role of Ureaplasma Species in Prenatal and Postnatal Morbidity of Preterm Infants: Current Concepts.

BACKGROUND: Ureaplasma species are considered commensals of the adult urogenital tract. Yet, in pregnancy, Ureaplasma parvum and Ureaplasma urealyticum have been associated with chorioamnionitis and preterm birth. In preterm infants, Ureaplasma respiratory tract colonization has been correlated with the development of bronchopulmonary dysplasia and has been implicated in the pathogenesis of other complications of prematurity. Controversies on the impact of Ureaplasma exposure on neonatal morbidity, however, remain, and recommendations for screening practices and therapeutic management in preterm infants are missing. SUMMARY: In this review, we outline clinical and experimental evidence of Ureaplasma-driven fetal and neonatal morbidity, critically examining inconsistencies across some of the existing studies. We explore underlying mechanisms of Ureaplasma-associated neonatal morbidity and discuss gaps in the current understanding including the interplay between Ureaplasma and the maternal urogenital tract and the preterm airway microbiome. Ultimately, we highlight the importance of adequate diagnostics and review the potential efficacy of anti-infective therapies. KEY MESSAGES: There is strong evidence that perinatal Ureaplasma exposure is causally related to the development of bronchopulmonary dysplasia, and there are conclusive data of the role of Ureaplasma in the pathogenesis of neonatal central nervous system infection. Observational and experimental findings indicate immunomodulatory capacities that might promote an increased risk of secondary infections. The burden of Ureaplasma exposure is inversely related to gestational age - leaving the tiniest babies at highest risk. A better knowledge of contributing pathogen and host factors and modulating conditions remains paramount to define screening and treatment recommendations allowing early intervention in preterm infants at risk.

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.

Ontogenesis of functional platelet subpopulations from preterm and term neonates to adulthood: The PLINIUS study.

Erythrocytes undergo a well-defined switch from fetal to postnatal circulation, which is mainly reflected by the stage-specific expression of hemoglobin chains. Perinatal alterations in thrombopoiesis are poorly understood. We assessed the ontogenesis of platelet phenotype and function from early prematurity to adulthood. We recruited 64 subjects comprising 7 extremely preterm (27-31 weeks gestational age), 25 moderately preterm (32-36 weeks), 10 term neonates, 8 infants (<2 years), 5 children (2-13 years), and 9 adults (>13 years). Blood was withdrawn at up to 3 different time points in neonates (t1: 0-2, t2: 3-7, and t3: 8-14 days after birth). We found that the expression levels of the major surface receptors for fibrinogen, collagen, vWF, fibronectin, and laminin were reduced but correlated with decreased platelet size, indicating a normal surface density. Although CD62P and CD63 surface exposure upon stimulation with TRAP-6, ADP, or U46619 was unaltered or only slightly reduced in neonates, GPIIb/IIIa inside-out and outside-in activation was blunted but showed a continuous increase until adulthood, correlating with the expression of the GPIIb/IIIa regulating tetraspanin CD151. Platelet subpopulation analysis using automated clustering revealed that neonates presented with a CD63+/PAC-1- pattern, followed by a continuous increase in CD63+/PAC-1+ platelets until adulthood. Our findings revealed that the number of platelet-monocyte and platelet-neutrophil aggregates, but not platelet-lymphocyte aggregates, is increased in neonates and that neonatal aggregate formation depends in part on CD62P activation. Our PLatelets In Neonatal Infants Study (PLINIUS) provides several lines of evidence that the platelet phenotype and function evolve continuously from neonates to adulthood.

The Delicate Skin of Preterm Infants: Barrier Function, Immune-Microbiome Interaction, and Clinical Implications.

The skin of preterm infants is a delicate organ with critical structural and functional differences as compared to term born infants. Unique features contribute to an increased susceptibility to injury, infection, thermal instability, and water loss. During rapid, often accelerated adaption of the physical barrier function of preterm skin, a parallel and mutual development of host skin immunity and skin microbiome seem to be crucial for skin homeostasis. Recent advances in molecular biology have enabled researchers to gain a deeper understanding of the microbial community composition of preterm skin and the important relationship with microbiome composition of other body sites. Nevertheless, several questions remain to be answered, including niche factors and environmental influences on skin maturation. In line with that, evidence-based guidelines on skin care practice in preterm infants are missing. This review articles aims to provide an overview of the current knowledge of preterm infant skin development including immune and barrier function, host-microbial interactions, and potential clinical implications.

European Consensus Guidelines on the Management of Respiratory Distress Syndrome: 2022 Update.

Respiratory distress syndrome (RDS) care pathways evolve slowly as new evidence emerges. We report the sixth version of "European Guidelines for the Management of RDS" by a panel of experienced European neonatologists and an expert perinatal obstetrician based on available literature up to end of 2022. Optimising outcome for babies with RDS includes prediction of risk of preterm delivery, appropriate maternal transfer to a perinatal centre, and appropriate and timely use of antenatal steroids. Evidence-based lung-protective management includes initiation of non-invasive respiratory support from birth, judicious use of oxygen, early surfactant administration, caffeine therapy, and avoidance of intubation and mechanical ventilation where possible. Methods of ongoing non-invasive respiratory support have been further refined and may help reduce chronic lung disease. As technology for delivering mechanical ventilation improves, the risk of causing lung injury should decrease, although minimising time spent on mechanical ventilation by targeted use of postnatal corticosteroids remains essential. The general care of infants with RDS is also reviewed, including emphasis on appropriate cardiovascular support and judicious use of antibiotics as being important determinants of best outcome. We would like to dedicate this guideline to the memory of Professor Henry Halliday who died on November 12, 2022.These updated guidelines contain evidence from recent Cochrane reviews and medical literature since 2019. Strength of evidence supporting recommendations has been evaluated using the GRADE system. There are changes to some of the previous recommendations as well as some changes to the strength of evidence supporting recommendations that have not changed. This guideline has been endorsed by the European Society for Paediatric Research (ESPR) and the Union of European Neonatal and Perinatal Societies (UENPS).

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.

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.

A case report of Sanfilippo syndrome - the long way to diagnosis.

BACKGROUND: Mucopolysaccharidosis type III (Sanfilippo syndrome) is a lysosomal storage disorder, caused by a deficiency in the heparan-N-sulfatase enzyme involved in the catabolism of the glycosaminoglycan heparan sulfate. It is characterized by early nonspecific neuropsychiatric symptoms, followed by progressive neurocognitive impairment in combination with only mild somatic features. In this patient group with a broad clinical spectrum a significant genotype-phenotype correlation with some mutations leading to a slower progressive, attenuated course has been demonstrated. CASE PRESENTATION: Our patient had complications in the neonatal period and was diagnosed with Mucopolysaccharidosis IIIa only at the age of 28 years. He was compound heterozygous for the variants p.R245H and p.S298P, the latter having been shown to lead to a significantly milder phenotype. CONCLUSIONS: The diagnostic delay is even more prolonged in this patient population with comorbidities and a slowly progressive course of the disease.

A first-in-human clinical study of a new SP-B and SP-C enriched synthetic surfactant (CHF5633) in preterm babies with respiratory distress syndrome: two-year outcomes.

OBJECTIVE: To assess at 24 months corrected age (CA) the neurological, respiratory, and general health status of children born prematurely from 27+0 to 33+6 weeks' gestation who were treated in a first-in-human study with a new fully synthetic surfactant (CHF5633) enriched with SP-B and SP-C proteins. OUTCOME MEASURES: Children were assessed using Bayley Scales of Infant Development (BSID), with a score below normal defined as BSID-II Mental Development Index score <70, or BSID-III cognitive composite score <85. In addition, a health status questionnaire was used to check for functional disability including respiratory problems and related treatments, sensory and neurodevelopment assessments, communication skills as well as the number of hospitalizations. RESULTS: 35 of 39 survivors had a neurodevelopmental assessment, 24 infants being evaluated by Bayley's Scales and 11 by health status questionnaires only. 23 children had scores within normal limits and one had BSID-III <85. The remaining 11 were judged clinically to have normal development. Health status questionnaires detected only issues that would normally be expected in preterm-born children. CONCLUSIONS: This assessment offers reassurance that treatment with CHF5633 surfactant was not associated with adverse neurodevelopmental, respiratory, or health outcomes by two years corrected age.

Report of two siblings with spondylodysplastic Ehlers-Danlos syndrome and B4GALT7 deficiency.

BACKGROUND: The spondylodysplastic Ehlers-Danlos subtype (OMIM #130070) is a rare connective tissue disorder characterized by a combination of connective tissue symptoms, skeletal features and short stature. It is caused by variants in genes encoding for enzymes involved in the proteoglycan biosynthesis or for a zinc transporter. PRESENTATION OF CASES: We report two brothers with a similar phenotype of short stature, joint hypermobility, distinct craniofacial features, developmental delay and severe hypermetropia indicative for a spondylodysplastic Ehlers-Danlos subtype. One also suffered from a recurrent pneumothorax. Gene panel analysis identified two compound heterozygous variants in the B4GALT7 gene: c.641G > A and c.723 + 4A > G. B4GALT7 encodes for galactosyltransferase I, which is required for the initiation of glycosaminoglycan side chain synthesis of proteoglycans. CONCLUSIONS: This is a first full report on two cases with spondylodysplastic Ehlers-Danlos syndrome and the c.723 + 4A > G variant of B4GALT7. The recurrent pneumothoraces observed in one case expand the variable phenotype of the syndrome.