Salivary biomarkers as pioneering indicators for diagnosis and severity stratification of pediatric long COVID.

Introduction: Long COVID, or post-acute sequelae of SARS-CoV-2 infection (PASC), manifests as persistent and often debilitating symptoms enduring well beyond the initial COVID-19 infection. This disease is especially worrying in children since it can seriously alter their development. Presently, a specific diagnostic test or definitive biomarker set for confirming long COVID is lacking, relying instead on the protracted presence of symptoms post-acute infection. Methods: We measured the levels of 13 biomarkers in 105 saliva samples (49 from children with long COVID and 56 controls), and the Pearson correlation coefficient was used to analyse the correlations between the levels of the different salivary biomarkers. Multivariate logistic regression analyses were performed to determine which of the 13 analysed salivary biomarkers were useful to discriminate between children with long COVID and controls, as well as between children with mild and severe long COVID symptoms. Results: Pediatric long COVID exhibited increased oxidant biomarkers and decreased antioxidant, immune response, and stress-related biomarkers. Correlation analyses unveiled distinct patterns between biomarkers in long COVID and controls. Notably, a multivariate logistic regression pinpointed TOS, ADA2, total proteins, and AOPP as pivotal variables, culminating in a remarkably accurate predictive model distinguishing long COVID from controls. Furthermore, total proteins and ADA1 were instrumental in discerning between mild and severe long COVID symptoms. Discussion: This research sheds light on the potential clinical utility of salivary biomarkers in diagnosing and categorizing the severity of pediatric long COVID. It also lays the groundwork for future investigations aimed at unravelling the prognostic value of these biomarkers in predicting the trajectory of long COVID in affected individuals.

Impact of COVID19 pandemic on patients with rare diseases in Spain, with a special focus on inherited metabolic diseases.

Introduction: The Covid-19 pandemic soon became an international health emergency raising concern about its impact not only on physical health but also on quality of life and mental health. Rare diseases are chronically debilitating conditions with challenging patient care needs. We aimed to assess the quality of life and mental health of patients with rare diseases in Spain, with a special focus on inherited metabolic disorders (IMD). Methods: A prospective case-control study was designed, comparing 459 patients suffering from a rare disease (including 53 patients with IMD) and 446 healthy controls. Quality of life (QoL) and mental health were assessed using validated scales according to age: KINDL-R and the Pediatric Symptom Checklist (PSC) for children and the WhoQoL-Bref questionnaire, GAD and PHQ-9 in adults. Results: First, children and adults (but not adolescents) with IMD showed greater psychological effects than controls (p = 0.022, p = 0.026 respectively). Second, when comparing QoL, only adult patients with IMD showed worse score than controls (66/100 vs 74,6/100 respectively, p = 0.017). Finally, IMD had better quality of life than other rare neurological and genetic diseases (p = 0.008) or other rare diseases (p < 0.001 respectively) but similar alteration of the mental status. Conclusions: Our data show that the pandemic had a negative impact on mental health that is more evident in the group of patients with IMD. Young age would behave as a protective factor on the perception of QoL. Furthermore, patients with IMD show a better QoL than other rare diseases.

Social, Academic, and Health Status Impact of Long COVID on Children and Young People: An Observational, Descriptive, and Longitudinal Cohort Study.

There is a lack of evidence of the health impacts due to long COVID among children and young people (CYP). The objective of this study is to determine the main clinical characteristics of long COVID in CYP and to investigate the academic, social, and health status impacts of long COVID in this population. An observational, descriptive, and longitudinal study on CYP who presented COVID-19 symptoms for more than twelve weeks after SARS-CoV-2 infection was performed between December 2020 and May 2021. Fifty CYP were included, with a median age of 14.1 years, 33 (66%) were female, and 17 (34%) had a relative diagnosed with long COVID. Since the initial infection and up to the first visit, CYP had persisting symptoms for a median of 4.1 months, and for 18 (36%) CYP these symptoms persisted for more than 6 months. Fatigue (100%), neurocognitive disorders (74%), muscular weakness (74%), and headache (72%) were the most reported symptoms. A total of 9 (18%) CYP could not attend school, 17 (34%) had a reduced schedule, 33 (66%) showed a decreased school performance, and 68% had stopped extracurricular activities. This preliminary study shows the impact that long COVID has on the health, academic, and social life of CYP.

Epigenetic profiling linked to multisystem inflammatory syndrome in children (MIS-C): A multicenter, retrospective study.

Background: Most children and adolescents infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remain asymptomatic or develop a mild coronavirus disease 2019 (COVID-19) that usually does not require medical intervention. However, a small proportion of pediatric patients develop a severe clinical condition, multisystem inflammatory syndrome in children (MIS-C). The involvement of epigenetics in the control of the immune response and viral activity prompted us to carry out an epigenomic study to uncover target loci regulated by DNA methylation that could be altered upon the appearance of MIS-C. Methods: Peripheral blood samples were recruited from 43 confirmed MIS-C patients. 69 non-COVID-19 pediatric samples and 15 COVID-19 pediatric samples without MIS-C were used as controls. The cases in the two groups were mixed and divided into discovery (MIS-C = 29 and non-MIS-C = 56) and validation (MIS-C = 14 and non-MIS-C = 28) cohorts, and balanced for age, gender and ethnic background. We interrogated 850,000 CpG sites of the human genome for DNA methylation variants. Findings: The DNA methylation content of 33 CpG loci was linked with the presence of MIS-C. Of these sites, 18 (54.5%) were located in described genes. The top candidate gene was the immune T-cell mediator ZEB2; and others highly ranked candidates included the regulator of natural killer cell functional competence SH2D1B; VWA8, which contains a domain of the Von Willebrand factor A involved in the pediatric hemostasis disease; and human leukocyte antigen complex member HLA-DRB1; in addition to pro-inflammatory genes such as CUL2 and AIM2. The identified loci were used to construct a DNA methylation profile (EPIMISC) that was associated with MIS-C in both cohorts. The EPIMISC signature was also overrepresented in Kawasaki disease patients, a childhood pathology with a possible viral trigger, that shares many of the clinical features of MIS-C. Interpretation: We have characterized DNA methylation loci that are associated with MIS-C diagnosis. The identified genes are likely contributors to the characteristic exaggerated host inflammatory response observed in these patients. The described epigenetic signature could also provide new targets for more specific therapies for the disorder. Funding: Unstoppable campaign of Josep Carreras Leukaemia Foundation, Fundació La Marató de TV3, Cellex Foundation and CERCA Programme/Generalitat de Catalunya.

Clinical characteristics, health care resource utilization and direct medical costs of Rotavirus hospitalizations in Spain (2013-2018).

Rotavirus (RV) is the most common cause of severe gastroenteritis (GE) in infants and young children worldwide and is associated with a significant clinical and economic burden. The objective of this study was to analyze the characteristics, healthcare resource utilization and the direct medical costs related to RVGE hospitalizations in Spain. An observational, multicenter, cross-sectional study was conducted from June 2013 to May 2018 at the pediatric departments of 12 hospitals from different Spanish regions. Children under 5 years of age admitted to the hospital with a confirmed diagnosis of RVGE were selected. Data on clinical characteristics, healthcare resource use and costs were collected from patient records and hospital databases. Most children hospitalized for RVGE did not have any previous medical condition or chronic disease. Forty-seven percent had previously visited the Emergency Room (ER), 27% had visited a primary care pediatrician, and 15% had received pharmacological treatment prior to hospital admission due to an RVGE episode. The average length of a hospital stay for RVGE was 5.6 days, and the mean medical costs of RVGE hospitalizations per episode ranged from 3,940€ to 4,100€. The highest direct medical cost was due to the hospital stay. This study showed a high burden of health resource utilization and costs related to the management of cases of RVGE requiring hospitalization. RV vaccination with high coverage rates should be considered to minimize the clinical and economic impacts of this disease on the health-care system.

Macrolide resistance and molecular typing of Mycoplasma pneumoniae infections during a 4 year period in Spain.

BACKGROUND: Mycoplasma pneumoniae (MP) causes community-acquired pneumonia affecting mainly children, and tends to produce cyclic outbreaks. The widespread use of macrolides is increasing resistance rates to these antibiotics. Molecular tools can help in diagnosis, typing and resistance detection, leading to better patient management. OBJECTIVES: To assess the MP genotypes and resistance pattern circulating in our area while comparing serological and molecular diagnosis of MP. METHODS: Molecular and serological diagnosis of MP was performed in 821 samples collected in Badalona (Barcelona, Spain) from 2013 to 2017. Multiple locus variable number tandem repeat analysis (MLVA) and macrolide resistance detection by pyrosequencing were performed in those cases positive by PCR. Presence of respiratory viruses and relevant clinical data were also recorded. RESULTS: MP was detected in 16.8% of cases by PCR, with an overall agreement with serology of 76%. Eleven different MLVA types were identified, with 4-5-7-2 (50.1%) and 3-5-6-2 (29.2%) being the most abundant, with the latter showing a seasonal increase during the study. A total of 8% of the strains harboured a point substitution associated with macrolide resistance, corresponding mainly to an A2063G 23S rRNA mutation and directly related to previous macrolide therapy. Analysis of respiratory viruses showed viral coinfections in most cases. CONCLUSIONS: Serological and molecular tools combined could improve MP diagnosis and the analysis of its infection patterns. Macrolide resistance is associated with previous therapy. Given that MP pneumonia usually resolves spontaneously, it should be reconsidered whether antibiotic treatment is suitable for all cases.

[Immunisation schedule of the Spanish Association of Paediatrics: 2019 recommendations]. / Calendario de vacunaciones de la Asociación Española de Pediatría: recomendaciones 2019.

The Advisory Committee on Vaccines of the Spanish Association of Paediatrics annually publishes the immunisation schedule considered optimal for children resident in Spain, according to available evidence on current vaccines. As regards funded immunisations, the 2+1 strategy (2, 4, 11 months) with hexavalent (DTPa-IPV-Hib-HB) and 13-valent pneumococcal vaccines are recommended. Administration of the 6-year booster dose with DTPa is recommended, with a poliomyelitis dose for children who had received the 2+1 scheme, as well as Tdap vaccine for adolescents and pregnant women in every pregnancy between 27 and 32 weeks gestation. The 2-dose scheme should be used for MMR (12 months and 3-4 years) and varicella (15 months and 3-4 years). MMRV vaccine could be applied as the second dose. Vaccination against HPV is recommended in both genders, preferably at 12 years of age. A stronger effort should be made to improve vaccination coverage. The new 9-valent vaccine is now available, expanding the coverage for both genders. Tetravalent meningococcal vaccine (MenACWY) is recommended at 12 months and 12-14 years, with a catch-up up at 19 years of age. It is also recommended in infants older than 6 weeks of age with risk factors, or travellers to countries with high incidence of ACWY meningococcal serogroups. As regards non-funded immunisations, it is recommended meningococcal B vaccination, with a 2+1 schedule, and requests that it be included in the National Immunisation Program. Vaccination against rotavirus is recommended in all infants.

[Child hospital admissions associated with influenza virus infection in 6 Spanish cities (2014-2016)]. / Hospitalizaciones infantiles asociadas a infección por virus de la gripe en 6 ciudades de España (2014-2016).

INTRODUCTION: There are only a limited number of studies on the impact of influenza in the Spanish child population. The present work intends to increase this knowledge by studying some key aspects, such as the incidence of hospital admissions, clinic variables, comorbidities, and the vaccination status in the hospitalised children. METHODS: A retrospective, observational study was conducted by reviewing the medical records of children under 15 years and hospitalised due to community acquired influenza confirmed microbiologically, during 2́flu seasons (2014-2015 and 2015-2016). The study was carried out in 10 hospitals of 6cities, which represent approximately 12% of the Spanish child population. RESULTS: A total of 907 children were admitted to hospital with main diagnosis of influenza infection (447 <2 years), estimating an average annual rate of hospitalisation incidence of 0.51 cases / 1,000 children (95% CI; 0.48-0.55). Just under half (45%) of the cases had an underlying disease considered a risk factor for severe influenza, and most (74%) had not been vaccinated. The percentage of children with underlying diseases increased with age, from 26% in children <6 months to 74% in children >10 years. Admission to the PICU was required in 10% (92) of the cases, mainly due to acute respiratory failure. CONCLUSION: Influenza continues to be an important cause of hospitalisation in the Spanish child population. Children <6 months of age and children with underlying diseases make up the majority (> 50%) of the cases. Many of the severe forms of childhood influenza that occur today could be avoided if current vaccination guidelines were met.

[Immunisation schedule of the Spanish Association of Paediatrics: 2018 recommendations]. / Calendario de vacunaciones de la Asociación Española de Pediatría (CAV-AEP): recomendaciones 2018.

The Advisory Committee on Vaccines of the Spanish Association of Paediatrics annually publishes the immunisation schedule considered optimal for children resident in Spain, according to available evidence on current vaccines. Regarding funded immunisations, 2+1 strategy (2, 4, 11-12 months) with hexavalent (DTPa-IPV-Hib-HB) and 13-valent pneumococcal vaccines are recommended. Administration of the 6-year booster dose with DTPa is recommended, and a poliomyelitis dose for children who had received the 2+1 scheme, as well as Tdap vaccine for adolescents and pregnant women in every pregnancy between 27 and 32 weeks' gestation. The two-dose scheme should be used for MMR (12 months and 2-4 years) and varicella (15 months and 2-4 years). MMRV vaccine could be applied as the second dose if available. Coverage of human papillomavirus vaccination in girls aged 12 with a two dose scheme (0, 6 months) should be improved. Information and recommendation for male adolescents about potential beneficial effects of this immunisation should be provided as well. The new 9 genotypes vaccine is now available, expanding the coverage for both gender. Regarding non-funded immunisations, Committee on Vaccines of the Spanish Association of Paediatrics recommends meningococcal B vaccination, with a 3+1 schedule, and requests to be included in the National Immunisation Program. Tetravalent meningococcal vaccine (MenACWY) is recommended to adolescents (14-18 years) who are going to live in countries with systematic vaccination against ACWY serogroups, and people >6 weeks of age with risk factors or travellers to countries with very high incidence. Vaccination against rotavirus is recommended in all infants.