CATSHL syndrome, a new family and phenotypic expansion.

We report the case of a 12-year-old girl and her father who both had marked postnatal tall stature, camptodactyly and clinodactyly, scoliosis and juvenile-onset hearing loss. The CATSHL (CAmptodactyly - Tall stature - Scoliosis - Hearing Loss syndrome) syndrome was suspected, and molecular analysis revealed a hitherto unreported, monoallelic variant c.1861C>T (p.Arg621Cys) in FGFR3. This variant affects the same residue, but is different than, the variant p.Arg621His reported in the two families with dominant CATSHL described so far. Interestingly, peg-shaped incisors were observed in the proband, a feature never reported in CATSHL but typical of another FGFR3-related condition, LADD (Lacrimo - Auricolo - Dento - Digital) syndrome. The FGFR3 p.Arg621Cys variant seems to be a newly identified cause of CATSHL syndrome with some phenotypic overlap with the LADD syndrome.

The Hospital Burden of Flu in Italy: a retrospective study on administrative data from season 2014-2015 to 2018-2019.

BACKGROUND: Every year in Italy, influenza affects about 4 million people. Almost 5% of them are hospitalised. During peak illness, enormous pressure is placed on healthcare and economic systems. This study aims to quantify the clinical and economic burden of severe influenza during 5 epidemic seasons (2014-2019) from administrative claims data. METHODS: Patients hospitalized with a diagnosis of influenza between October 2014, and April 2019, were analyzed. Clinical characteristics and administrative information were retrieved from health-related Administrative Databases (ADs) of 4 Italian Local Health Units (LHUs). The date of first admission was set as the Index Date (ID). A follow-up period of six months after ID was considered to account for complications and re-hospitalizations, while a lookback period (2 years before ID) was set to assess the prevalence of underlying comorbidities. RESULTS: Out of 2,333 patients with severe influenza, 44.1% were adults ≥ 65, and 25.6% young individuals aged 0-17. 46.8% had comorbidities (i.e., were at risk), mainly cardiovascular and metabolic diseases (45.3%), and chronic conditions (24.7%). The highest hospitalization rates were among the elderly (≥ 75) and the young individuals (0-17), and were 37.6 and 19.5/100,000 inhabitants/year, respectively. The average hospital stay was 8 days (IQR: 14 - 4). It was higher for older individuals (≥ 65 years, 11 days, [17 - 6]) and for those with comorbidities (9 days, [16 - 6]), p-value < 0.001. Similarly, mortality was higher in elderly and those at risk (p-value < 0.001). Respiratory complications occurred in 12.7% of patients, and cardiovascular disorders in 5.9%. Total influenza-related costs were €9.7 million with hospitalization accounting for 95% of them. 47.3% of hospitalization costs were associated with individuals ≥ 65 and 52.9% with patients at risk. The average hospitalisation cost per patient was € 4,007. CONCLUSIONS: This retrospective study showed that during the 2014-2019 influenza seasons in Italy, individuals of extreme ages and those with pre-existing medical conditions, were more likely to be hospitalized with severe influenza. Together with complications and ageing, they worsen patient's outcome and may lead to a prolonged hospitalization, thus increasing healthcare utilization and costs. Our data generate real-world evidence on the burden of influenza, useful to inform public health decision-making.

Paracetamol and ibuprofen fixed-dose combination for the management of acute mild-to-moderate pain in children: strengthening and enhancing of result of Nominal Group Technique through Delphi consensus.

BACKGROUND: Paracetamol and ibuprofen are the most commonly used drugs for pain treatment in children and their combination has shown improved analgesic effect compared to treatment with either drug alone. Current literature lacks specific guidelines regarding the settings in which this combination should be adopted. METHODS: The survey, conducted with Delphi methodology, involved 75 hospital and outpatient pediatricians with clinical experience in the management of pain in children. Pediatricians involved were asked to validate or not the results of the previous NominalGroup Tecnique (NGT) consensus and thus specify the optimal clinical settings in which the paracetamol/ibuprofen fixed-dose combination could be adopted. RESULTS: The results confirm the importance of the fixed-dose paracetamol and ibuprofen combination for the control of mild-to-moderate acute pain in children. Particularly, this association seems to be appropriate in case of headache, earache, odontalgia and musculoskeletal pain, and in specific settings such as post-operative and post-procedural pain. The broadening of the panel brought to slight variations in clinical management practices between hospital and outpatient specialists. Nonetheless, overall consensus supports the notion that the fixed dose combination is more efficacious than monotherapies and it is well tolerated. Moreover, experts unanimously agree on the usefulness of the combination for caregivers, leading to improved adherence and effectiveness. CONCLUSIONS: Both the NGT consensus and the broader Delphi consensus confirm the usefulness of the paracetamol-ibuprofen fixed-dose combination in pediatric pain. This is attributed to its superior effectiveness compared to monotherapies, a good tolerability profile, and improved compliance and ease of use. Some pain settings related to chronic, inflammatory and rheumatological pathologies remain to be investigated to evaluate the use of this combination.

The overlapping of phenotypes in Wiedemann-Steiner, Kleefstra and Coffin-Siris syndromes: a study of eleven patients.

BACKGROUND: Some chromatinopathies may present with common clinical findings (intellectual disability, brain and limb malformation, facial dysmorphism). Furthermore, one of their cardinal shared features is growth dysregulation.We aimed to assess and deepen this resemblance in three specific conditions, namely Wiedemann-Steiner (WDSTS), Kleefstra (KLEFS1) and Coffin-Siris syndrome (CSS1), with a particular focus on possible metabolic roots. METHODS: Eleven patients were enrolled, three with WDSTS, five with KLEFS1 and three with CSS1, referring to Fondazione IRCCS Ca' Granda Ospedale Maggiore, Milan, Italy. We performed both a physical examination with detailed anthropometric measurements and an evaluation of the patients' REE (rest energy expenditure) by indirect calorimetry, comparing the results with age- and sex-matched healthy controls. RESULTS: We observed new clinical features and overlap between these conditions suggesting that different disturbances of epigenetic machinery genes can converge on a common effect, leading to overlapping clinical phenotypes.The REE was not distinguishable between the three conditions and healthy controls. CONCLUSIONS: Epigenetic machinery plays an essential role both in growth regulation and in neurodevelopment; we recommend evaluating skeletal [craniovertebral junction abnormalities (CVJ) polydactyly], otolaryngological [obstructive sleep apnea syndrome (OSAs), recurrent otitis media], dental [tooth agenesis, talon cusps], and central nervous system (CNS) [olfactory bulbs and cerebellum anomalies] features. These features could be included in monitoring guidelines. Further studies are needed to deepen the knowledge about energy metabolism.

A long way to syndromic short stature.

BACKGROUND: Silver-Russell Syndrome (SRS, MIM #180860) is a clinically and genetically heterogeneous disorder characterized by intrauterine and postnatal growth retardation; SRS is also accompanied by dysmorphic features such as triangular facial appearance, broad forehead, body asymmetry and significant feeding difficulties. The incidence is unknown but estimated at 1:30,000-100,000 live births. The diagnosis of SRS is guided by specific criteria described in the Netchine-Harbison clinical scoring system (NH-CSS). CASE PRESENTATION: Hereby we describe four patients with syndromic short stature in whom, despite fitting the criteria for SRS genetic analysis (and one on them even meeting the clinical criteria for SRS), molecular analysis actually diagnosed a different syndrome. Some additional features such as hypotonia, microcephaly, developmental delay and/or intellectual disability, and family history of growth failure, were actually discordant with SRS in our cohort. CONCLUSIONS: The clinical resemblance of other short stature syndromes with SRS poses a risk of diagnostic failure, in particular when clinical SRS only criteria are met, allowing SRS diagnosis in the absence of a positive result of a genetic test. The presence of additional features atypical for SRS diagnosis becomes a red flag for a more extensive and thorough analysis. The signs relevant to the differential diagnosis should be valued as much as possible since a correct diagnosis of these patients is the only way to provide the appropriate care pathway, a thorough genetic counselling, prognosis definition, follow up setting, appropriate monitoring and care of possible medical problems.

Omalizumab may protect allergic patients against COVID-19: A systematic review.

Omalizumab, which downregulates the immunoglobulin E (IgE) receptor site on plasmacytoid dendritic cells and thereby increases interferon-α (INF-α) production, may shorten the duration of viral infections by enhancing the antiviral immunity. A systematic review was conducted to investigate whether previous anti-IgE treatment with omalizumab could protect against SARS-CoV-2 disease ("COVID-19") (infection, disease duration, and severity), and whether IFN-α upregulation could be involved. The research included articles published from March 2020 to January 2022. An accurate search was performed on bibliographic biomedical database (MEDLINE - Pubmed, SCOPUS, EMBASE, BIOMED CENTRAL, Google scholar, COCHRANE LIBRARY, ClinicalTrial.gov) including cohorts, case reports and reviews. Different methods were used, based on the study design, to assess the quality of eligible studies. Several authors link omalizumab to a possible protection against viruses, but they often refer to studies carried out before the pandemic and with viruses other than SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) (eg, rhinoviruses -RV). Few cases of COVID-19 patients treated with omalizumab have been recorded, and, in most of them, no increased susceptibility to severe disease was observed. According to these data, the current indication is to continue omalizumab therapy during the pandemic. Moreover, although omalizumab may enhance the antiviral immune response even for SARS-CoV-2, further studies are needed to confirm this hypothesis. It would be helpful to establish a registry of omalizumab-treated (or in treatment) patients who have developed COVID-19. Finally, randomized controlled trials could be able to demonstrate the effect of omalizumab in protecting against severe SARS-CoV-2, through IFN-α upregulation or other immunological pathways.

Paracetamol and ibuprofen combination for the management of acute mild-to-moderate pain in children: expert consensus using the Nominal Group Technique (NGT).

BACKGROUND: Acute pain is a common symptom in children of all ages, and is associated with a variety of conditions. Despite the availability of guidelines, pain often remains underestimated and undertreated. Paracetamol and ibuprofen are the most commonly used drugs for analgesia in Pediatrics. Multimodal pain management by using a combination of paracetamol and ibuprofen results in greater analgesia. METHODS: An investigation using the Nominal Group Technique was carried out between May and August 2022. Two open (non-anonymous) questionnaires were consecutively sent to a Board of ten clinicians to understand their opinions on the use of the oral paracetamol and ibuprofen association. Answers were examined in a final meeting where conclusions were drawn. RESULTS: The board achieved a final consensus on a better analgesic power of paracetamol and ibuprofen in fixed-dose combination as compared to monotherapy, without compromising safety. Strong consensus was reached on the opinion that the fixed-dose combination of paracetamol and ibuprofen may be a useful option in case of inefficacy of one or other drug as monotherapy, especially in case of headaches, odontalgia, earache, and musculoskeletal pain. The use of the fixed combination may be also considered suitable for postoperative pain management. CONCLUSIONS: The use of the fixed-dose combination may represent advantage in terms of efficacy and safety, allowing a better control of the dose of both paracetamol and ibuprofen as monotherapy, thus minimizing the risk of incorrect dosage. However, the limited evidence available highlights the need for future well designed studies to better define the advantages of this formulation in the various therapeutic areas.

SARS-CoV-2 infection in children: A 24 months experience with focus on risk factors in a pediatric tertiary care hospital in Milan, Italy.

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in children is characterized by a wide variety of expressions ranging from asymptomatic to, rarely, critical illness. The basis of this variability is not yet fully understood. The aim of this study was to identify clinical and genetic risk factors predisposing to disease susceptibility and progression in children. Methods: We enrolled 181 consecutive children aged less than 18 years hospitalized with or for SARS-CoV-2 infection during a period of 24 months. Demographic, clinical, laboratory, and microbiological data were collected. The development of coronavirus disease 2019 (COVID-19)-related complications and their specific therapies were assessed. In a subset of 79 children, a genetic analysis was carried out to evaluate the role of common COVID-19 genetic risk factors (chromosome 3 cluster; ABO-blood group system; FUT2, IFNAR2, OAS1/2/3, and DPP9 loci). Results: The mean age of hospitalized children was 5.7 years, 30.9% of them being under 1 year of age. The majority of children (63%) were hospitalized for reasons different than COVID-19 and incidentally tested positive for SARS-CoV-2, while 37% were admitted for SARS-CoV-2 infection. Chronic underlying diseases were reported in 29.8% of children. The majority of children were asymptomatic or mildly symptomatic; only 12.7% developed a moderate to critical disease. A concomitant pathogen, mainly respiratory viruses, was isolated in 53.3%. Complications were reported in 7% of children admitted for other reasons and in 28.3% of those hospitalized for COVID-19. The respiratory system was most frequently involved, and the C-reactive protein was the laboratory test most related to the development of critical clinical complications. The main risk factors for complication development were prematurity [relative risk (RR) 3.8, 95% confidence interval (CI) 2.4-6.1], comorbidities (RR 4.5, 95% CI 3.3-5.6), and the presence of coinfections (RR 2.5, 95% CI 1.1-5.75). The OAS1/2/3 risk variant was the main genetic risk factor for pneumonia development [Odds ratio (OR) 3.28, 95% CI 1-10.7; p value 0.049]. Conclusion: Our study confirmed that COVID-19 is generally less severe in children, although complications can develop, especially in those with comorbidities (chronic diseases or prematurity) and coinfections. Variation at the OAS1/2/3 genes cluster is the main genetic risk factor predisposing to COVID-19 pneumonia in children.

Evaluation of Six Years of Appropriateness Level of Blood Transfusion in a Pediatric Ward.

BACKGROUND: Blood transfusion can be considered as a life-saving treatment and is a primary health management topic. This study aims to assess the appropriateness of blood transfusion performed in a large tertiary hospital in Italy. METHODS: a multispecialist team composed oof hematologists, public health experts and pediatricians analyzed blood transfusions performed between 2018 and 2022 in the pediatric wards comparing the appropriateness with the available NHS guidelines available. Patients' characteristics, clinical features and blood component's data were collected and analyzed. RESULTS: considering 147 blood transfusions performed in 2018-2022, only eight (5.4%) were performed according to guidelines, while 98 (66.7%) were driven by clinicians' expertise, especially for anemia in genetic syndromes (30) (20.5%) and autoimmune diseases (20) (13.6%). Thirty-nine (26.5%) transfusions could be considered as inappropriate, while two (1.4%) blood packs were never been transfused after being requested. CONCLUSIONS: This analysis is one of the first performed to assess the appropriateness of blood component transfusions comparing their compliance to NHS guidelines. The importance of this analysis can be explained first by the clinical point of view and second by the economic one.

Severity of SARS-CoV-2 infection in a hospital population: a clinical comparison across age groups.

BACKGROUND: Children tend to have milder forms of COVID-19 than adults, however post-acute complications have been observed also in the paediatric population. In this study, we compared COVID-19-related outcomes and long-term complications between paediatric and adult patients infected by SARS-CoV-2. METHODS: The study is based on individuals enrolled from October 2020 to June 2021 in the DECO COVID-19 multicentre prospective study supported by the Italian Ministry of Health (COVID-2020-12371781). We included individuals with RT-PCR -confirmed SARS-CoV-2 infection, who were evaluated in the emergency department and/or admitted to COVID-dedicated wards. The severity of SARS-CoV-2 infection was compared across age groups (children/adolescents aged < 18 years, young/middle-aged adults aged 18-64 years and older individuals) through the relative risk (RR) of severe COVID-19. Severity was defined by: 1) hospitalization due to COVID-19 and/or 2) need or supplemental oxygen therapy. RR and corresponding 95% confidence intervals were estimated using log-binomial models. RESULTS: The study included 154 individuals, 84 (54.5%) children/adolescents, 50 (32.5%) young/middle-aged adults and 20 (13%) older adults. Compared to young/middle-aged adults the risk of hospitalization was lower among paediatric patients (RR: 0.49, 95% CI: 0.32-0.75) and higher among older adults (RR: 1.52, 95% CI: 1.12-2.06). The RR of supplemental oxygen was 0.12 (95% CI: 0.05-0.30) among children/adolescents and 1.46 (95% CI: 0.97-2.19) among older adults. Three children developed multisystem inflammatory syndrome (MIS-C), none was admitted to intensive care unit or reported post-acute Covid-19 complications. CONCLUSIONS: Our study confirms that COVID-19 is less severe in children. MIS-C is a rare yet severe complication of SARS-CoV-2 infection in children and its risk factors are presently unknown.

From clinical to molecular diagnosis: relevance of diagnostic strategy in two cases of branchio-oto-renal syndrome - case report.

BACKGROUND: Branchio-oto-renal syndrome (BOR) is an autosomal dominant disorder characterized by deafness, branchiogenic malformations and renal abnormalities. Pathogenic variants in EYA1, SIX1 and SIX5 genes cause almost half of cases; copy number variants (CNV) and complex genomic rearrangements have been revealed in about 20% of patients, but they are not routinely and commonly included in the diagnostic work-up. CASE PRESENTATION: We report two unrelated patients with BOR syndrome clinical features, negative sequencing for BOR genes and the identification of a 2.65 Mb 8q13.2-13.3 microdeletion. CONCLUSIONS: We highlight the value of CNV analyses in high level of suspicion for BOR syndrome but negative sequencing for BOR genes and we propose an innovative diagnostic flow-chart to increase current detection rate. Our report confirms a mechanism of non-allelic homologous recombination as causing this recurrent 8q13.2-13.3 microdeletion. Moreover, considering the role of PRDM14 and NCOA2 genes, both involved in regulation of fertility and deleted in our patients, we suggest the necessity of a longer follow-up to monitor fertility issues or additional clinical findings.

Meningococcal Disease in Pediatric Age: A Focus on Epidemiology and Prevention.

Meningococcal disease is caused by Neisseria meningitidis; 13 serogroups have been identified and differentiated from each other through their capsular polysaccharide. Serotypes A, B, C, W, X, and Y are responsible for nearly all infections worldwide. The most common clinical manifestations are meningitis and invasive meningococcal disease, both characterized by high mortality and long-term sequelae. The infection rate is higher in children younger than 1 year and in adolescents, who are frequently asymptomatic carriers. Vaccination is the most effective method of preventing infection and transmission. Currently, both monovalent meningococcal vaccines (against A, B, and C serotypes) and quadrivalent meningococcal vaccines (against serogroups ACYW) are available and recommended according to local epidemiology. The purpose of this article is to describe the meningococcal vaccines and to identify instruments that are useful for reducing transmission and implementing the vaccination coverage. This aim could be reached by switching from the monovalent to the quadrivalent vaccine in the first year of life, increasing vaccine promotion against ACYW serotypes among adolescents, and extending the free offer of the anti-meningococcal B vaccine to teens, co-administering it with others proposed in the same age group. Greater awareness of the severity of the disease and increased health education through web and social networks could represent the best strategies for promoting adhesion and active participation in the vaccination campaign. Finally, the development of a licensed universal meningococcal vaccine should be another important objective.

Corrigendum: Disappearance of seasonal respiratory viruses in children under two years old during COVID-19 pandemic: A monocentric retrospective study in Milan, Italy.

[This corrects the article DOI: 10.3389/fped.2021.721005.].

Incidental finding of APC deletion in a child: double trouble or double chance? - a case report.

BACKGROUND: 22q11.2 deletion syndrome is one of the most common genomic disorders, characterized by the variable presence of facial dysmorphisms, congenital cardiac defects, velopharyngeal insufficiency/cleft palate, thymic hypoplasia/aplasia, immunodeficiency, parathyroid hypoplasia, developmental delay, learning disabilities, psychiatric disorders, renal, ocular, and skeletal malformations, hearing loss and laryngeal abnormalities. Chromosomal microarray (CMA) hybridization is one of the most performed diagnostic tests but as a genome wide analysis, it can point out relevant incidental copy number variations. CASE PRESENTATION: We report the case of a 2-year-old boy that came to our attention for mild psychomotor delay, poor growth, and minor facial anomalies. Considering a diagnosis of 22q11.2 deletion syndrome, we performed CMA that not only confirmed our diagnosis, but also pointed out an additional de novo 5q21.3q22.2 microdeletion, encompassing APC gene. As a result of the genetic testing we enrolled the patient in a tailored surveillance protocol that enabled the early detection of a hepatoblastoma. The child underwent surgical and chemotherapic treatments with complete cancer eradication. CONCLUSIONS: The concurrent finding of an expected result and an additional deletion of APC gene represents an example of a relevant issue about the health and ethical management of secondary findings revealed by genome-wide tests. Furthermore, this report highlights the need to develop dedicated surveillance guidelines for children with APC-related polyposis and raise the question whether to suspect and screen for APC-related conditions in cases of sporadic hepatoblastomas.

Disappearance of Seasonal Respiratory Viruses in Children Under Two Years Old During COVID-19 Pandemic: A Monocentric Retrospective Study in Milan, Italy.

Background: The containment measures adopted during COVID-19 pandemic have influenced the epidemiology of other respiratory viruses. Aim: We analyzed the modification of the incidence and etiology of lower respiratory tract infections (LRTIs) in young children during COVID-19 pandemic. Methods: Case series of all children under 2 years old hospitalized at a tertiary care Hospital in the Center of Milan, Italy diagnosed with LRTIs in three consecutive winter seasons (from the 1st of November to the last day of February in 2018/2019, 2019/2020 and 2020/2021). We compared the number of hospitalizations and viral detections in the 2020/2021 with the average of 2018/2019 and 2019/2020 (pre-COVID-19) using the Poisson distribution. Results: we enrolled 178 patients (66 from 2018/2019, 96 from 2019/2020, 16 from 2020/2021) 94 males (53%) and 84 females (47%), with a median (IQR) age of 5 (2-13) months. The number of hospitalizations during the 2020/2021 season was 80% lower than the average of the pre-COVID-19 seasons (16 vs. 81, p<0.001). Overall, 171 (96%) patient's nasopharyngeal aspirate (NPA) detected at least one virus (110, 64%, single-detection, 61, 36%, co-detections). In 2020/2021 we observed the disappearance of Respiratory Syncytial virus (0 vs. 54, p < 0.001), Influenza virus (0 vs. 6.5, p = 0.002), Metapneumovirus (0 vs. 8, p < 0.001), Parainfluenza viruses (0 vs. 3.5, p = 0.03) and a significant reduction of Adenovirus (2 vs. 7, p = 0.03), Bocavirus (2 vs. 7.5, p = 0.02) and Enterovirus (1 vs. 5, p = 0.04). No significant difference was found for Rhinoviruses (14 cases vs. 17, p = 0.2), other Coronaviruses (0 vs. 2, p = 0.1), and Cytomegalovirus (1 vs. 1, p = 0.7). Conclusions: We observed a striking reduction in hospitalizations due to LRTIs and a modification of the etiology, with enveloped viruses mainly affected.

Impact of maternal diphtheria-tetanus-acellular pertussis vaccination on pertussis booster immune responses in toddlers: Follow-up of a randomized trial.

BACKGROUND: Transplacentally transferred antibodies induced by maternal pertussis vaccination interfere with infant immune responses to pertussis primary vaccination. We evaluated whether this interference remains in toddlers after booster vaccination. METHODS: In a prior phase IV, observer-blind, placebo-controlled, randomized study (NCT02377349), pregnant women in Australia, Canada and Europe received intramuscular tetanus-reduced-antigen-content diphtheria-three-component acellular pertussis vaccine (Tdap group) or placebo (control group) at 270/7-366/7 weeks' gestation, with crossover immunization postpartum. Their infants were primed (study NCT02422264) and boosted (at 11-18 months; current study NCT02853929) with diphtheria-tetanus-three-component acellular pertussis-hepatitis B virus-inactivated poliovirus/Haemophilus influenzae type b vaccine (DTaP-HepB-IPV/Hib) and 13-valent pneumococcal conjugate vaccine. Immunogenicity before and after booster vaccination, and reactogenicity and safety of the booster were evaluated descriptively. RESULTS: 263 (Tdap group) and 277 (control group) toddlers received a DTaP-HepB-IPV/Hib booster. Pre-booster vaccination, observed geometric mean concentrations (GMCs) for the three pertussis antigens and diphtheria were 1.4-1.5-fold higher in controls than in the Tdap group. No differences were observed for the other DTaP-HepB-IPV/Hib antigens. One month post-booster vaccination, booster response rates for pertussis antigens were ≥ 92.1% and seroprotection rates for the other DTaP-HepB-IPV/Hib antigens were ≥ 99.2% in both groups (primary objective). Higher post-booster GMCs were observed in controls versus the Tdap group for anti-filamentous hemagglutinin (1.2-fold), anti-pertussis toxoid (1.5-fold) and anti-diphtheria (1.4-fold). GMCs for the other DTaP-HepB-IPV/Hib antigens were similar between groups. Serious adverse events were reported for three toddlers (controls, not vaccination-related). One death occurred pre-booster (Tdap group, not vaccination-related). CONCLUSIONS: As a consequence of interference of maternal pertussis antibodies with infant immune responses to pertussis primary vaccination, pertussis antibody concentrations were still lower in toddlers from Tdap-vaccinated mothers before DTaP-HepB-IPV/Hib booster vaccination. After the booster, antibody concentrations were lower for filamentous hemagglutinin and pertussis toxoid but not for pertactin. The clinical significance of this interference requires further evaluation. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: NCT02853929.

Impact of tetanus-diphtheria-acellular pertussis immunization during pregnancy on subsequent infant immunization seroresponses: follow-up from a large randomized placebo-controlled trial.

BACKGROUND: Pertussis immunization during pregnancy results in high pertussis antibody concentrations in young infants but may interfere with infant immune responses to post-natal immunization. METHODS: This phase IV, multi-country, open-label study assessed the immunogenicity and safety of infant primary vaccination with DTaP-HepB-IPV/Hib and 13-valent pneumococcal conjugate vaccine (PCV13). Enrolled infants (6-14 weeks old) were born to mothers who were randomized to receive reduced-antigen-content diphtheria-tetanus-three-component acellular pertussis vaccine (Tdap group) or placebo (control group) during pregnancy (270/7-366/7 weeks' gestation) with crossover immunization postpartum. All infants received 2 or 3 DTaP-HepB-IPV/Hib and PCV13 doses according to national schedules. Immunogenicity was assessed in infants pre- and 1 month post-primary vaccination. The primary objective was to assess seroprotection/vaccine response rates for DTaP-HepB-IPV/Hib antigens 1 month post-primary vaccination. RESULTS: 601 infants (Tdap group: 296; control group: 305) were vaccinated. One month post-priming, seroprotection rates were 100% (diphtheria; tetanus), ≥98.5% (hepatitis B), ≥95.9% (polio) and ≥94.5% (Hib) in both groups. Vaccine response rates for pertussis antigens were significantly lower in infants whose mothers received pregnancy Tdap (37.5-77.1%) versus placebo (90.0-99.2%). Solicited and unsolicited adverse event rates were similar between groups. Serious adverse events occurred in 2.4% (Tdap group) and 5.6% (control group) of infants, none were vaccination-related. CONCLUSIONS: Pertussis antibodies transferred during pregnancy may decrease the risk of pertussis infection in the first months of life but interfere with the infant's ability to produce pertussis antibodies, the clinical significance of which remains unknown. Safety and reactogenicity results were consistent with previous experience. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: NCT02422264.

Immunogenicity, transplacental transfer of pertussis antibodies and safety following pertussis immunization during pregnancy: Evidence from a randomized, placebo-controlled trial.

BACKGROUND: Pertussis immunization during pregnancy is recommended in many countries. Data from large randomized controlled trials are needed to assess the immunogenicity, reactogenicity and safety of this approach. METHODS: This phase IV, observer-blind, randomized, placebo-controlled, multicenter trial assessed immunogenicity, transplacental transfer of maternal pertussis antibodies, reactogenicity and safety of a reduced-antigen-content diphtheria-tetanus-three-component acellular pertussis vaccine (Tdap) during pregnancy. Women received Tdap or placebo at 27-36 weeks' gestation with crossover ≤ 72-hour-postpartum immunization. Immune responses were assessed before the pregnancy dose and 1 month after, and from the umbilical cord at delivery. Superiority (primary objective) was reached if the lower limits of the 95% confidence intervals (CIs) of the pertussis geometric mean concentration (GMC) ratios (Tdap/control) in cord blood were ≥ 1.5. Solicited and unsolicited adverse events (AEs) and pregnancy-/neonate-related AEs of interest were recorded. RESULTS: 687 pregnant women were vaccinated (Tdap: N = 341 control: N = 346). Superiority of the pertussis immune response (maternally transferred pertussis antibodies in cord blood) was demonstrated by the GMC ratios (Tdap/control): 16.1 (95% CI: 13.5-19.2) for anti-filamentous hemagglutinin, 20.7 (15.9-26.9) for anti-pertactin and 8.5 (7.0-10.2) for anti-pertussis toxoid. Rates of pregnancy-/neonate-related AEs of interest, solicited general and unsolicited AEs were similar between groups. None of the serious AEs reported throughout the study were considered related to maternal Tdap vaccination. CONCLUSIONS: Tdap vaccination during pregnancy resulted in high levels of pertussis antibodies in cord blood, was well tolerated and had an acceptable safety profile. This supports the recommendation of Tdap vaccination during pregnancy to prevent early-infant pertussis disease. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: NCT02377349.