Children with Down syndrome are high-risk for severe respiratory syncytial virus disease

Risk factors for respiratory syncytial virus-associated acute lower respiratory infection in children under 5 years: An updated systematic review and meta-analysis

OBJECTIVES

Respiratory syncytial virus (RSV) is a leading cause of acute lower respiratory infection (ALRI) in young children. With substantial advances in RSV research, we aimed to conduct an updated systematic review of risk factors for RSV-ALRI in children under 5 years.

METHODS

We updated our previously published literature search to November 2022 among three English databases and additionally searched three Chinese databases (from January 1995) to identify all relevant publications. We performed random-effects meta-analyses to estimate the pooled odds ratio (OR) and 95% confidence interval (CI) for each risk factor and each outcome (RSV-ALRI in the community and RSV-ALRI hospitalization).

RESULTS

A total of 47 studies were included (26 from the updated search). Indoor air pollution was identified as a possible risk factor for RSV-ALRI in the community (OR 1.45, 95% CI: 1.10-1.90). The identified risk factors for RSV-ALRI hospitalization fall into four categories: demographic (male sex, Māori and Pacific ethnicities vs European or other ethnicities), pre- and post-neonatal (prematurity, low birth weight, small for gestational age, maternal smoking during pregnancy or lactation, maternal age <30 years vs 30-34 years, multiparity, caesarean section vs vaginal), household and environmental (having siblings, passive smoking, maternal asthma, daycare centre attendance) and health and medical conditions (any chronic diseases, bronchopulmonary dysplasia, HIV infections, congenital heart disease, Down syndrome, cystic fibrosis, previous asthma). The pooled ORs ranged from 1.14 to 4.55.

CONCLUSION

Our findings on the risk factors for RSV-ALRI help identify RSV high-risk groups, which has important implications for RSV prevention at both individual and population levels.

Bronchiolitis: evidence-based management in high-risk infants in the intensive care setting

AIM

Systematically review the management of infants with severe bronchiolitis in a paediatric intensive care unit (PICU) setting with a focus on high-risk infants to identify gaps in evidence-based knowledge.

METHODS

This systematic review utilised Preferred Reporting Items for Systematic Review and Meta-analysis Protocols (PRISMA-P) to examine the literature on the PICU management of bronchiolitis in infants <24 months old. Three databases, Embase, PubMed and Medline, were searched and higher levels of evidence I, II and III were included.

RESULTS

There were 455 papers reviewed and 26 met the inclusion criteria. Furthermore, 19 of these studied respiratory interventions such as positive airway pressure and oxygen delivery. The remaining 7 examined: erythropoietin, caffeine, dexamethasone, protein supplementation, ribavirin, respiratory syncytial virus immune globulin, or diuretic therapy. Of the 26 studies, 20 excluded infants with high-risk conditions. Therapies showing favourable outcomes included Heliox, prophylactic dexamethasone pre-extubation, protein supplementation, and diuretic use.

CONCLUSIONS

Clinical trials for bronchiolitis management frequently exclude high-risk children. Innovative study design in the future may improve access to clinical trials for the management of bronchiolitis in high-risk infants in a PICU setting.

IMPACT

Clinical trials for bronchiolitis management frequently exclude high-risk children. We review the evidence base for the management of an under-investigated patient demographic in the setting of acute bronchiolitis. Randomised controlled trials are needed to determine the efficacy of management strategies for bronchiolitis in high-risk infants in a paediatric intensive care setting.

Exploring the Complex Interplay of Obesity, Allergic Diseases, and Sleep-Disordered Breathing in Children

This narrative review study investigates the correlations between obesity, allergies, and sleep-disordered breathing in pediatric populations. Searches for pertinent articles were conducted on the Medline PubMed Advanced Search Builder, Scopus, and Web of Science databases from unlimited to April 2024. Sleep-disordered breathing causes repeated upper airway obstructions, leading to apneas and restless sleep. Childhood obesity, which affects around 20% of children, is often associated with sleep-disordered breathing and allergies such as asthma and allergic rhinitis. It is distinguished between diet-induced obesity (resulting from excess of diet and physical inactivity) and genetic obesity (such as is seen in Down syndrome and Prader-Willi syndrome). In children with diet-induced obesity, chronic inflammation linked to weight can worsen allergies and increase the risk and severity of asthma and rhinitis. Furthermore, the nasal congestion typical of rhinitis can contribute to upper respiratory tract obstruction and obstructive sleep apnea. A vicious circle is created between asthma and sleep-disordered breathing: uncontrolled asthma and sleep-disordered breathing can worsen each other. In children with genetic obesity, despite alterations in the immune system, fewer allergies are observed compared to the broader population. The causes of this reduced allergenicity are unclear but probably involve genetic, immunological, and environmental factors. Additional research is necessary to elucidate the underlying mechanisms. The present narrative review study emphasizes the importance of jointly evaluating and managing allergies, obesity, and obstructive sleep apnea in children considering their close interconnection.

Risk Factors for Poor Outcomes in Children Hospitalized With Virus-associated Acute Lower Respiratory Infections: A Systematic Review and Meta-analysis

BACKGROUND

Acute lower respiratory infection (ALRI) caused by respiratory viruses is among the most common causes of hospitalization and mortality in children. We aimed to identify risk factors for poor outcomes in children <5 years old hospitalized with ALRI caused by respiratory syncytial virus (RSV), influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

METHODS

We searched Embase, Medline and Global Health databases and included observational studies reporting risk factors for poor outcomes (defined as use of supplemental oxygen, mechanical ventilation, intensive care unit admission, prolonged hospital stay and mortality) published between January 2011 and January 2023. Two authors independently extracted data on study characteristics, outcomes and risk factors. Due to limited data, meta-analyses were only conducted for RSV-ALRI poor outcome risk factors using random effects model when there were at least 3 studies.

RESULTS

We included 30 studies. For RSV-related ALRI, significant risk factors based on meta-analysis were: neurological disease [odds ratio (OR): 6.14; 95% confidence intervals (CIs): 2.39-15.77], Down's syndrome (5.43; 3.02-9.76), chronic lung disease (3.64; 1.31-10.09), immunocompromised status (3.41; 1.85-6.29), prematurity (2.98; 1.93-4.59), congenital heart disease (2.80; 1.84-4.24), underlying disease (2.45; 1.94-3.09), age <2 months (2.29; 1.78-2.94), age <6 months (2.08; 1.81-2.39), viral coinfection (2.01; 1.27-3.19), low birth weight (1.88; 1.19-2.95) and being underweight (1.80; 1.38-2.35). For influenza-related ALRI, chronic conditions and age 6-24 months were identified as risk factors for poor outcomes. Cardiovascular disease, immunosuppression, chronic kidney disease, diabetes and high blood pressure were reported as risk factors for mortality due to SARS-CoV-2 associated ALRI.

CONCLUSIONS

These findings might contribute to the development of guidelines for prophylaxis and management of ALRI caused by RSV, influenza and SARS-CoV-2.

Respiratory Syncytial Virus Vaccination in Older Adults: Considerations for Use and Shared Clinical Decision-Making

PURPOSE

To evaluate the impact of two newly U.S. Food and Drug Administration-approved respiratory syncytial virus (RSV) vaccines, RSVpreF3 (Arexvy™, GSK) and RSVpreF (Abrysvo™, Pfizer), on morbidity in older adults. RSV is known to cause significant health issues in this demographic.

METHOD

The current article reviews Phases 1 and 2 and Phase 3 published clinical trials, the recommendations for immunization practices outlined in the Morbidity and Mortality Weekly Report, and other relevant literature on RSV infection and vaccine coadministration. A case vignette is also included to illustrate an example of the shared clinical decision-making process for vaccination.

RESULTS

Findings suggest that RSVpreF3 and RSVpreF vaccines effectively reduce health complications of RSV in older adults. Successful integration of these vaccines with other immunizations is also highlighted, emphasizing the role of an interprofessional team in this process.

CONCLUSION

The introduction of RSVpreF3 and RSVpreF vaccines represents a significant advancement in the management of RSV in older adults. This article underscores the importance of shared clinical decision-making in vaccine administration and the effective coordination of an interprofessional team for coadministration with other vaccines. [Journal of Gerontological Nursing, 50(3), 7-12.].

Cytomegalovirus Pneumonia in a Patient with Down Syndrome

Down syndrome (DS) is a chromosomal disorder due to the presence of an additional chromosome 21 that causes intellectual deficit and physical anomalies and predisposes patients to develop infections throughout their lives. Pneumonias are more serious in patients with DS, requiring hospitalization, and they represent an important cause of mortality in this population. Cytomegalovirus (CMV) causes widespread and serious infections in immunocompromised individuals, affecting the respiratory tract and, when causing interstitial pneumonia, associated with a high mortality rate. However, CMV-induced pneumonia is not reported in DS patients. The prevalence and severity of CMV respiratory infections in subjects with DS is unknown. This case describes a 50-year-old female patient with DS who developed extensive bilateral pneumonia with severe respiratory failure which required hospitalization in intensive care, intubation, and mechanical ventilation after approximately 10 days of empiric antibiotic and anitimycotic therapy for fever, cough, and dyspnea. The patient was diagnosed with CMV pneumonia and recovered after treatment with ganciclovir. To the best of our knowledge, this is the first reported case of CMV pneumonia in a patient with DS. This case aims to highlight that CMV pneumonia in individuals with DS can be a life-threatening condition. It also clarifies the importance of early diagnosis of infections from opportunistic pathogens such as CMV to ensure timely and efficient treatment.

Human Respiratory Syncytial Virus Epidemiological Burden in Pediatric Outpatients in Italy: A Systematic Review

BACKGROUND

Human respiratory syncytial virus (hRSV) is a key contributor to lower respiratory tract infections (LRTIs), affecting children aged 0-5 years and often leading to outpatient visits, emergency department utilization, and hospitalization. With the development of hRSV vaccines for mitigation, understanding the epidemiological impact of hRSV infections among 0-5-year-old pediatric outpatients in Italy is crucial.

METHODS

This systematic review conducted searches on PubMed, Embase, Scopus, and the International HTA Database, yielding 20,845 English and Italian records from January 2000 to July 2022.

RESULTS

Six eligible articles were identified following inclusion and exclusion criteria. These studies demonstrated hRSV-positivity proportions ranging from 18% to 41% in pediatric outpatients with respiratory infections. However, data comparability was hindered by diverse diagnostic approaches, data sources, sample populations, and study designs. Notably, hRSV-positivity showed temporal variability, rising from 23.8% (2001-2002) to 40.6% (2019-2020). This trend could stem from evolving epidemiological factors, heightened clinician awareness in hRSV diagnosis, or more sensitive molecular techniques.

CONCLUSION

As the first review of its kind, this study underscores the need for more comprehensive data to inform effective preventive strategies against hRSV-related burdens in pediatric outpatients.

Assessing the burden of bronchiolitis and lower respiratory tract infections in children ≤24 months of age in Italy, 2012-2019

Background

Bronchiolitis is the most common lower respiratory tract infection (LRTI) in children and is mainly caused by the Respiratory Syncytial Virus (RSV). Bronchiolitis presents seasonally and lasts about five months, usually between October to March, with peaks of hospitalizations between December and February, in the Northern Hemisphere. The burden of bronchiolitis and RSV in primary care is not well understood.

Materials and methods

This retrospective analysis used data from Pedianet, a comprehensive paediatric primary care database of 161 family paediatricians in Italy. We evaluated the incidence rates (IR) of all-cause bronchiolitis (ICD9-CM codes 466.1, 466.11 or 466.19), all-cause LRTIs, RSV-bronchiolitis and RSV-LRTIs in children from 0 to 24 months of age, between January 2012 to December 2019. The role of prematurity (<37 weeks of gestational age) as a bronchiolitis risk factor was evaluated and expressed as odds ratio.

Results

Of the 108,960 children included in the study cohort, 7,956 episodes of bronchiolitis and 37,827 episodes of LRTIs were recorded for an IR of 47 and 221 × 1,000 person-years, respectively. IRs did not vary significantly throughout the eight years of RSV seasons considered, showing a seasonality usually lasting five months, between October and March, while the peak of incidence was between December and February. Bronchiolitis and LRTI IRs were higher during the RSV season, between October and March, regardless of the month of birth, with bronchiolitis IR being higher in children aged ≤12 months. Only 2.3% of bronchiolitis and LRTI were coded as RSV-related. Prematurity and comorbidity increased the risk of bronchiolitis; however, 92% of cases happened in children born at term, and 97% happened in children with no comorbidities or otherwise healthy.

Conclusions

Our results confirm that all children aged ≤24 months are at risk of bronchiolitis and LRTI during the RSV season, regardless of the month of birth, gestational age or underlying health conditions. The IRs of bronchiolitis and LRTI RSV-related are underestimated due to the poor outpatient epidemiological and virological surveillance. Strengthening the surveillance system at the paediatric outpatient level, as well as at the inpatient level, is needed to unveil the actual burden of RSV-bronchiolitis and RSV-LRTI, as well as to evaluate the effectiveness of new preventive strategies for anti-RSV.

Pulmonary complications in children with Down syndrome: A scoping review

CONTEXT

Down syndrome (DS) is a prevalent chromosomal disorder associated with a wide range of congenital anomalies and other health problems.

OBJECTIVES

To give a scoping overview of encountered lower airway problems (both infectious and non-infectious) in DS children.

DATA SOURCES

We systematically searched the MEDLINE and PubMed databases for relevant publications.

STUDY SELECTION

Studies were eligible if they were original studies about pediatric airway problems in DS and were evaluated by the PRISMA guidelines.

DATA EXTRACTION

Data concerning patient characteristics, study methods and outcomes were critically reviewed.

RESULTS

Sixty papers were included. These were reviewed and summarized by topic, i.e. airway anomalies, dysphagia and aspiration, lower respiratory tract infections (and bronchiolitis in particular), pulmonary hypertension and other. Respiratory problems are proven to be a frequent and a major health burden in DS children. Airway anomalies (both single and multiple) are more prevalent and require a specific approach. A large proportion of DS children have (often silent) aspiration, resulting in protracted and difficult-to-treat symptoms. Respiratory tract infections are usually more severe and associated with an increased need for (prolonged) hospitalization. Pulmonary hypertension, wheeze and some other rare conditions are more commonly encountered in DS.

LIMITATIONS

Large number of studies and high levels of study heterogeneity.

CONCLUSIONS

Several lower airway problems are more frequent and more complex in children with DS. These findings emphasize the need for a multidisciplinary approach by an experienced team allowing for a prompt diagnosis, proper management and improved long term outcome.

Respiratory Syncytial Virus-Associated Hospitalizations in Children With Neurological Disorders, 2006-2015

BACKGROUND

We quantified the risk of respiratory syncytial virus (RSV) hospitalizations and severe outcomes among children with neurological disorders.

METHODS

We estimated RSV-specific and RSV-associated hospitalization rates using International Classification of Diseases, Ninth Revision (ICD-9) codes from 2 insurance claims IBM MarketScan Research Databases (Commercial and Multi-State Medicaid) from July 2006 through June 2015. For comparison, a simple random sample of 10% of all eligible children was selected to represent the general population. Relative rates (RRs) of RSV hospitalization were calculated by dividing rates for children with neurological disorders by rates for children in the general population by age group and season.

RESULTS

The RSV-specific hospitalization rate for children with any neurological condition was 4.2 (95% confidence interval [CI]: 4.1, 4.4) per 1000 person-years, and the RSV-associated hospitalization rate was 7.0 (95% CI: 6.9, 7.2) per 1000 person-years among children <19 years of age. Among privately insured children, the overall RR of RSV hospitalization in children with neurological disorders compared with the general population was 10.7 (95% CI: 10.0, 11.4) for RSV-specific hospitalization and 11.1 (95% CI: 10.5, 11.7) for RSV-associated hospitalizations. Among children in Medicaid, the RSV-specific hospitalization RR was 6.1 (95% CI: 5.8, 6.5) and the RSV-associated hospitalization RR was 6.4 (95% CI: 6.2, 6.7) compared with the general population.

CONCLUSIONS

Our population-based study of children with neurological disorders found that the risk of RSV hospitalization was 6 to 12 times higher among children with neurological disorders than among the general pediatric population. These findings should be considered when determining who should be targeted for current and future RSV interventions.

Burden of illness in infants and young children hospitalized for respiratory syncytial virus: A rapid review

Respiratory syncytial virus (RSV) infections are common among young children and represent a significant burden to patients, their families and the Canadian health system. Here we conduct a rapid review of the burden of RSV illness in children 24 months of age or younger. Four databases (Medline, Embase, Cochrane Database of Clinical Trials, ClinicalTrials.gov from 2014 to 2018), grey literature and reference lists were reviewed for studies on the following: children with or without a risk factor, without prophylaxis and with lab-confirmed RSV infection. Of 29 studies identified, 10 provided within-study comparisons and few examined clinical conditions besides prematurity. For infants of 33-36 weeks gestation (wGA) versus term infants, there was low-to-moderate certainty evidence for an increase in RSV-hospitalizations (n=599,535 infants; RR 2.05 [95% CI 1.89-2.22]; 1.3 more per 100 [1.1-1.5 more]) and hospital length of stay (n=7,597 infants; mean difference 1.00 day [95% CI 0.88-1.12]). There was low-to-moderate certainty evidence of little-to-no difference for infants born at 29-32 versus 33-36 wGA for hospitalization (n=12,812 infants; RR 1.20 [95% CI 0.92-1.56]). There was low certainty evidence of increased mechanical ventilation for hospitalized infants born at 29-32 versus 33-35 wGA (n=212 infants; RR 1.58, 95% CI 0.94-2.65). Among infants born at 32-35 wGA, hospitalization for RSV in infancy may be associated with increased wheeze and asthma-medication use across six-year follow-up (RR range 1.3-1.7). Children with versus without Down syndrome may have increased hospital length of stay (n=7,206 children; mean difference 3.00 days, 95% CI 1.95-4.05; low certainty). Evidence for other within-study comparisons was of very low certainty. In summary, prematurity is associated with greater risk for RSV-hospitalization and longer hospital length of stay, and Down syndrome may be associated with longer hospital stay for RSV. Respiratory syncytial virus-hospitalization in infancy may be associated with greater wheeze and asthma-medication use in early childhood. Lack of a comparison group was a major limitation for many studies.

Risk factors for respiratory syncytial virus bronchiolitis hospitalizations in children with chronic diseases

BACKGROUND

Respiratory syncytial virus (RSV) bronchiolitis is the most common lower respiratory tract disorder causing hospitalization in infants. Due to decreased hospitalization rates of premature infants following Palivizumab immune prophylaxis, the proportion of infants with chronic diseases not eligible for Palivizumab has increased.

AIM

To characterize infants hospitalized during 2014-2018 with RSV bronchiolitis, to compare between those with and without chronic conditions, and to identify risk factors for severe disease.

METHODS

This retrospective study analyzed demographic and clinical data of patients younger than 2 years admitted with bronchiolitis during four consecutive RSV seasons.

RESULTS

Of 1124 hospitalizations due to RSV bronchiolitis, 244 (22%) were in infants with chronic diseases. Although 20/1124 qualified for RSV prophylaxis, only eight received immune prophylaxis. Compared to otherwise healthy infants, children with chronic diseases had longer hospitalizations, median 4.8 days (interquartile range [IQR]: 3.4-8.3) versus 3.7 days (IQR: 2.7-5.1), p < .001; and higher pediatric intensive care unit (PICU) and readmission rates (9% vs. 4.5%, p = .007% and 3% vs. 1%, p = .055, respectively). Children with Down's syndrome comprised 2% of all hospitalizations, but 8% of PICU admissions; their median length of hospitalization was 10.7 days (IQR: 6.6-17.6). Respiratory tract malformations were present in 2% of hospitalizations, and comprised 4% of PICU admissions.

CONCLUSION

Among infants admitted with RSV bronchiolitis, those with chronic diseases had longer hospitalizations and higher rates of transfer to the PICU. Children with multiple comorbidities, and especially those with Down's syndrome, are at particularly high risk for severe hospitalization and may benefit from RSV immune prophylaxis.

A Bayesian approach to real-time spatiotemporal prediction systems for bronchiolitis

Respiratory Syncytial Virus (RSV) induced bronchiolitis is a common lung infection and a major cause of infant hospitalization and mortality. Unfortunately, there is no known cure for RSV but several vaccines are in various stages of clinical trials. Currently, immunoprophylaxis is a preventative measure consisting of a series of monthly shots that should be administered at the start, and throughout, peak RSV season. Thus, the successful implementation of immunoprophylaxis is contingent upon understanding when outbreak seasons will begin, peak, and end. In this research we estimate the seasonal epidemic curves of RSV induced bronchiolitis using a spatially varying change point model. Further, in a novel approach and using the fitted change point model, we develop a historical matching algorithm to generate real time predictions of seasonal curves for future years.

The impact of obstructive sleep apnea on bronchiolitis severity in children with Down syndrome

OBJECTIVES

Acute bronchiolitis commonly causes respiratory failure in children ≤2 years, and is particularly severe in those with Down syndrome (DS). Obstructive sleep apnea (OSA), common in DS, is also associated with respiratory complications. However, it is unknown whether OSA is associated with worse outcomes in children with and without DS, hospitalized with bronchiolitis. We hypothesized that in children with bronchiolitis, OSA is associated with worse outcomes in those with DS, independent of DS-related comorbidities.

METHODS

Hospital discharge records of children with bronchiolitis aged ≤2 years were obtained for 1997-2012 from the Kid's Inpatient Database. The primary outcome was invasive mechanical ventilation (IMV), and secondary outcomes were non-invasive mechanical ventilation (NIMV), length of hospital stay, and inflation-adjusted cost of hospitalization (IACH). Multivariable regression was conducted to ascertain the associations between OSA and primary and secondary outcomes accounting for DS-associated comorbidities.

RESULTS

There were 928,961 hospitalizations for bronchiolitis. The DS group with bronchiolitis (n = 8697) was more likely to have OSA [241 (2.77%) vs 1293 (0.14%), p < 0.001] compared to the non-DS group (n = 920,264). Multivariable logistic regression showed that OSA was associated with IMV (adjusted odds ratio [OR], 3.32 [95% CI 2.54-4.35], p < 0.0001) in all children with bronchiolitis; and in those with DS, it was associated with IMV (adjusted OR, 2.34 [95% CI 1.38-3.97], p = 0.002), NIMV (adjusted OR, 8.21 [95% CI 4.48-15.04], p < 0.0001) and IACH (adjusted β, 0.18 [95% CI 0.02-0.34], p = 0.031).

CONCLUSIONS

OSA is independently associated with assisted ventilation in all children hospitalized with bronchiolitis, regardless of DS-associated comorbidities in those with DS. The severity of bronchiolitis in children with DS may be driven by the high prevalence of OSA.

Risk factors for RSV associated acute lower respiratory infection poor outcome and mortality in young children: A systematic review and meta-analysis

Respiratory syncytial virus associated acute lower respiratory infection (RSV-ALRI) constitutes a substantial disease burden in young children. We aimed to identify all studies investigating the risk factors of RSV-ALRI poor outcome or mortality in young children.We carried out a systematic literature review across 7 databases with data from studies published from January 1995 to December 2019. We defined poor outcome as need for prolonged hospital stay, oxygen supplementation, mechanical ventilation or intensive care unit (ICU) admission. Quality of all eligible studies was assessed according to modified GRADE criteria. We conducted meta-analyses to estimate odds ratio (OR) with 95% confidence intervals (CI) for individual risk factors. We identified 27 eligible studies, which investigated 20 risk factors for RSV-ALRI poor outcome and/or mortality in children younger than 5 years old, in comparison to those with RSV-ALRI who did not have poor outcome or mortality. Among those risk factors, 6 had statistically significant associations with RSV-ALRI poor outcome: any comorbidity (OR 2.69 (95% CI 1.89-3.83)), congenital heart disease (3.40 (95% CI 2.14-5.40)), prematurity with gestational age (GA) <37 weeks (1.75 (95% CI 1.31-2.36)), prematurity with GA ≤32 weeks (2.68 (95% CI 1.43-5.04)), age <3 months (4.91 (95% CI 1.64-14.71)), age <6 months (2.02 (95% CI 1.73-2.35)). Apart from age <3 months, the meta-estimate ORs for all other risk factors were based on studies using multivariable analysis. For mortality, only prematurity with GA <37 weeks had a significant meta-estimate of OR 3.81 (95% CI 1.68-8.63) based on univariable analysis.This study represents a comprehensive report of the association between various risk factors and RSV-ALRI poor outcome and mortality in young children. More research should be carried out to elucidate risk factors associated with poor outcome and mortality using multivariable analysis.

Clinical Presentation and Successful Management of an Infant With Down Syndrome and COVID-19 in Riyadh, Saudi Arabia

Coronavirus is a serious, global disease. Down syndrome (DS) is characterized by immune dysregulation, has various anatomical variations, and is considered as comorbidity. These variations mean that children with DS are at risk of developing a severe case of COVID-19 if the virus is contracted. Here, we report the first case of COVID-19 in a four-month-old infant girl with DS and congenital heart disease (CHD) who was treated in Al-Imam Abdulrahman Al Faisal Hospital in the first health cluster in Riyadh, Saudi Arabia. The medical management and clinical outcome of the infant are reviewed. The infant was admitted after having received previous treatment from other hospitals, with a deteriorating condition. The patient had developed a rash, and oxygen support was required in addition to her baseline medication (furosemide and captopril). Ten days post admission, the patient's condition improved, and she became clinically stable. She was then discharged after two consecutive negative nasopharyngeal swabs. Based on the reported case, infants with DS and CHD should be considered a high-risk patient in terms of COVID-19 infection and require close observation.

SARS-CoV-2 Infection in Patients with Down Syndrome, Congenital Heart Disease, and Pulmonary Hypertension: Is Down Syndrome a Risk Factor?

With increasing information available about the epidemiology, pathophysiology, and management of patients affected with severe acute respiratory syndrome corona virus-2 infection, patients with Down syndrome, congenital heart disease, airway obstruction, and pulmonary hypertension present a unique challenge. This case series describes 3 patients with Down syndrome and respiratory failure secondary to coronavirus infection.

Discharge Before Return to Respiratory Baseline in Children With Neurologic Impairment

BACKGROUND

Children with neurologic impairment (NI) are commonly hospitalized with acute respiratory infections (ARI). These children frequently require respiratory support at baseline and are often discharged before return to respiratory baseline.

OBJECTIVE

To determine if discharge before return to respiratory baseline is associated with reutilization among children with NI hospitalized with ARI.

METHODS

This single-center retrospective cohort study included children with NI aged 1 to 18 years hospitalized with ARI who required increased respiratory support between January 2010 and September 2015. The primary exposure was discharge before return to respiratory baseline. The primary outcome was 30-day hospital reutilization. A generalized estimating equation was used to examine the association between exposure and outcome while accounting for within-patient clustering and patient-level clinical complexity and illness severity.

RESULTS

In the 632 hospitalizations experienced by 366 children, children were discharged before return to respiratory baseline in 30.4% of hospitalizations. Compared with those hospitalizations in which children were discharged at baseline, hospitalizations with a discharge before return to respiratory baseline were more likely to be for privately insured, technology-dependent children with respiratory comorbidities. Compared with discharges at respiratory baseline, discharges with increased respiratory support had no difference in 30-day reutilization (32.8% vs 31.8%; P = .81; adjusted OR 0.80, 95% CI 0.51-1.26).

CONCLUSIONS

Among children with NI hospitalized with ARI, discharge before return to respiratory baseline was common, but it was not associated with hospital reutilization. Return to respiratory baseline may not be a necessary component of discharge criteria in this population.

Respiratory Syncytial Virus-related Death in Children With Down Syndrome: The RSV GOLD Study

BACKGROUND

Respiratory syncytial virus (RSV) is a major cause of mortality in children younger than 5 years worldwide. Systematic reviews have shown that Down syndrome (DS) is an independent risk factor for severe RSV infection. We aimed to describe demographic and clinical characteristics of children with DS who died with RSV infection.

METHODS

We performed a retrospective case series in which data were shared by individual researchers, research networks and physicians worldwide as part of the RSV Global Online Database study. We included children with DS who died when younger than 5 years of age with laboratory-confirmed RSV infection.

RESULTS

We included 53 children with DS and RSV-related mortality from 20 countries in 5 continents. Five (9.4%) children were from low-income or lower-middle-income countries. Median age at time of death was 6.0 months [interquartile range (IQR): 3.00-12.0]. Thirteen (24.5%) children were born term and had no other risk factors for severe RSV disease. In total, 36 (67.9%) children had congenital heart disease, 8 (15.1%) had chronic lung disease and 1 (1.9%) had congenital immunodeficiency. Duration of hospitalization was significantly longer for children with DS compared with children without DS [median length of stay, 13 days (IQR: 6.8-21.0) vs. 8 days (IQR: 3.0-18.5), P=0.005].

CONCLUSIONS

One-fourth of children with DS and RSV-confirmed death did not have risk factors for severe RSV disease, indicating that DS is an important risk factor for RSV-related mortality. Age distribution at time of death demonstrates that maternal vaccination would not be sufficient to protect children with DS against RSV-related mortality.

Risk factors for hospitalized respiratory syncytial virus disease and its severe outcomes

Introduction

Respiratory syncytial virus (RSV) is a major cause of hospital admission for acute lower respiratory tract infection in young children.

Objectives

We aimed to identify risk factors for hospitalized RSV disease and its severe outcomes.

Methods

We conducted a retrospective cohort study analyzing data of a ICD‐10‐code‐based hospital surveillance for severe acute respiratory infections (SARI). Using univariable and multivariable logistic regression analysis, we assessed age‐group, gender, season, and underlying medical conditions as possible risk factors for RSV and its severe outcomes including ICU admission, application of ventilator support, and death, respectively.

Results

Of the 413 552 patients hospitalized with SARI in the database, 8761 were diagnosed with RSV from week 01/2009 to 20/2018 with 97% (8521) aged <5 years. Among children aged <5 years, age‐groups 0‐5 months (OR: 20.29, 95% CI: 18.37‐22.41) and 6 months‐1 year (OR: 4.59, 95% CI: 4.16‐5.06), and underlying respiratory and cardiovascular disorders specific to the perinatal period (OR: 1.32, 95% CI: 1.11‐1.57) were risk factors for being diagnosed with RSV. Age‐group 0‐5 months (OR: 2.39, 95% CI: 1.45‐3.94), low birth weight (OR: 6.77, 95% CI: 1.28‐35.71), preterm newborn (OR: 6.71, 95% CI: 2.19‐20.61), underlying respiratory and cardiovascular disorders specific to the perinatal period (OR: 4.97, 95% CI: 3.36‐7.34), congenital malformation of the heart (OR: 3.65, 95% CI: 1.90‐7.02), congenital malformation of the great vessels (OR: 3.50, 95% CI: 1.10‐11.18), congenital defect originating in perinatal period (OR: 4.07, 95% CI: 1.71‐9.70), cardiovascular disease (OR: 5.19, 95% CI: 2.77‐9.72), neurological disorders (OR: 6.48, 95% CI: 3.76‐11.18), blood disease (OR: 3.67, 95% CI: 1.98‐6.79), and liver disease (OR: 14.99, 95% CI: 1.49‐150.82) contributed to ICU admission in RSV cases.

Conclusions

Using ICD‐10‐based surveillance data allows to identify risk factors for hospitalized RSV disease and its severe outcomes, and quantify the risk in different age‐groups.

Respiratory syncytial virus infection: why does disease severity vary among individuals?

Introduction: Respiratory syncytial virus (RSV) is the most common cause of acute lower respiratory tract infections in infancy. While many infants are infected with RSV, the nature and severity of the disease vary among individuals. RSV causes bronchiolitis, pneumonia, and asthma exacerbation. However, most children infected with RSV have only mild upper airways disease and may be asymptomatic.Areas covered: Despite efforts to elucidate mechanisms for the various clinical responses to RSV infection, they remain largely unknown, suggesting that susceptibility and disease are influenced by multiple intrinsic and extrinsic factors. This article reviews the available literature on the field of RSV disease severity and discusses important factors associated to susceptibility and different disease outcome.Expert opinion: The severity of RSV-induced illness is a phenomenon that depends on a variety of graded mechanisms of interaction between the host, virus, and environment. This may lead to differences in the intensity of immune response in the lung and different courses of the disease. By characterizing, classifying, and grading the affecting factors in high-risk patients versus those who do not fall ill by RSV, we may find therapies or point to disease-limiting medications.

Immune Dysregulation in Children With Down Syndrome

Down syndrome (DS) is the most common genetic syndrome associated with immune defects. The extent of immune dysregulation in DS is substantial, spanning the innate and adaptive systems and including anomalies in: T and B cells, monocytes, neutrophil chemotaxis, circulating cytokines, and suboptimal antibody responses which all contribute to an increased risk of infections, poorer clinical outcomes and chronic inflammation in this vulnerable cohort. Other aspects of innate immunity may also be abnormal and contribute to the increased morbidity and warrant further interrogation such as: gamma delta T cell function, the inflammasome, Toll-like receptors and their pathways. Pharmacotherapies such as pavilizumab, pneumococcal and influenza immunizations, as well as potential immunoprophylactic agents such as pidotimod, azithromycin and Broncho-Vaxom may help alleviate the infectious consequences. Children with DS need to be managed with a heightened sense of awareness and urgency in the setting of sepsis and signs of chronic inflammation need regular screening and appropriate follow up.

Estimating seasonal onsets and peaks of bronchiolitis with spatially and temporally uncertain data

RSV bronchiolitis (an acute lower respiratory tract viral infection in infants) is the most common cause of infant hospitalizations in the United States (US). The only preventive intervention currently available is monthly injections of immunoprophylaxis. However, this treatment is expensive and needs to be administered simultaneously with seasonal bronchiolitis cycles in order to be effective. To increase our understanding of bronchiolitis timing, this research focuses on identifying seasonal bronchiolitis cycles (start times, peaks, and declinations) throughout the continental US using data on infant bronchiolitis cases from the US Military Health System Data Repository. Because this data involved highly personal information, the bronchiolitis dates in the dataset were "jittered" in the sense that the recorded dates were randomized within a time window of the true date. Hence, we develop a statistical change point model that estimates spatially varying seasonal bronchiolitis cycles while accounting for the purposefully introduced jittering in the data. Additionally, by including temperature and humidity data as regressors, we identify a relationship between bronchiolitis seasonality and climate. We found that, in general, bronchiolitis seasons begin earlier and are longer in the southeastern states compared to the western states with peak times lasting approximately 1 month nationwide.

Hospitalization for Respiratory Syncytial Virus in Children with Down Syndrome Less than 2 Years of Age: A Systematic Review and Meta-Analysis

OBJECTIVES

To compare the respiratory syncytial virus (RSV)-related hospitalization rate, hospital length of stay (LOS), and need for assisted ventilation in children aged <2 years with Down syndrome and those without Down syndrome.

STUDY DESIGN

MEDLINE, Embase, and CINAHL databases were searched from inception up to December 2017. Studies that provided data on RSV-related hospitalization in children aged <2 years with Down syndrome and those without Down syndrome were included. Data were independently extracted in pairs by 2 reviewers and synthesized with random-effects meta-analysis.

RESULTS

In 10 studies including a total of 1 748 209 children, 12.6% of the children with Down syndrome (491 of 3882) were hospitalized with RSV infection. The presence of Down syndrome was associated with a significantly higher risk of RSV-related hospitalization (relative risk [RR], 6.06; 95% CI, 4.93-7.45; I² = 65%; Grading of Recommendations, Assessment, Development and Evaluation [GRADE], moderate). RSV-related LOS (mean difference, 2.11 days; 95% CI, 1.47-2.75 days; I² = 0%; GRADE, low), and the need for assisted ventilation (RR, 5.82; 95% CI, 1.81-18.69; I² = 84%; GRADE, low). Children with Down syndrome without congenital heart disease (RR, 6.31; 95% CI, 4.83-8.23; GRADE, moderate) also had a significantly higher risk of RSV-related hospitalization. The risk of RSV-related hospitalization remained significant in the subgroup of children aged <1 year (RR, 6.25; 95% CI, 4.71-8.28; GRADE, high).

CONCLUSION

RSV-related hospitalization, hospital LOS, and the need for assisted ventilation are significantly higher in children with Down syndrome aged <2 years compared with those without Down syndrome. The results should prompt reconsideration of the need for routine RSV prophylaxis in children with Down syndrome up to 2 years of age.

Underlying factors of recurrent infections in patients with down syndrome

Down syndrome is the most common chromosomal aberration. Patientswith Down syndrome suffer more infections than those without the disease. Underlying immunological disorders are consideredto be the reason for the increasing frequency of infections in patients with Down syndrome. In addition, some anatomical abnormalities in the respiratory tractaccompanying Down syndrome can disturb the innate immunity and contribute to the increase in infection rate. Respiratory tract infections are one of the most common causes of mortality in patients with Down syndrome. Awareness of the underlying reason for frequent respiratory tract infections should result in a decrease in mortality among these patients and contribute to an improvementin their quality of life.

Down Syndrome and the Risk of Severe RSV Infection: A Meta-analysis

CONTEXT

Down syndrome (DS) is the most common chromosomal condition in live-born infants worldwide, and lower respiratory infection caused by respiratory syncytial virus (RSV) is a leading cause of hospital admissions.

OBJECTIVE

To evaluate RSV-associated morbidity among children with DS compared with a population without DS.

DATA SOURCES

Four electronic databases were searched.

STUDY SELECTION

All cohorts or case-control studies of DS with an assessment of RSV infection and the associated morbidity or mortality were included without language restriction.

DATA EXTRACTION

Two reviewers independently reviewed all studies. The primary outcomes were hospital admission and mortality. Secondary outcomes included length of hospital stay, oxygen requirement, ICU admission, need for respiratory support, and additional medication use.

RESULTS

Twelve studies (n = 1 149 171) from 10 different countries met the inclusion criteria; 10 studies were cohort studies, 1 study was retrospective, and 1 study had both designs. DS was associated with a higher risk of hospitalization (odds ratio [OR]: 8.69; 95% confidence interval [CI]: 7.33-10.30; I² = 11%) and mortality (OR: 9.4; 95% CI: 2.26-39.15; I² = 38%) compared with what was seen in controls. Children with DS had an increased length of hospital stay (mean difference: 4.73 days; 95% CI: 2.12-7.33; I² = 0%), oxygen requirement (OR: 6.53; 95% CI: 2.22-19.19; I² = 0%), ICU admission (OR: 2.56; 95% CI: 1.17-5.59; I² = 0%), need for mechanical ventilation (OR: 2.56; 95% CI: 1.17-5.59; I² = 0%), and additional medication use (OR: 2.65 [95% CI: 1.38-5.08; I² = 0%] for systemic corticosteroids and OR: 5.82 [95% CI: 2.66-12.69; I² = 0%] for antibiotics) than controls.

LIMITATIONS

DS subgroups with and without other additional risk factors were not reported in all of the included studies.

CONCLUSIONS

Children with DS had a significantly higher risk of severe RSV infection than children without DS.

Palivizumab use in infants with Down syndrome-report from the German Synagis™ Registry 2009-2016

Infants with Down syndrome (DS) face an increased risk of respiratory tract infections. Recent studies describe DS as independent risk factor for a complicated clinical course in infants with respiratory syncytial virus (RSV) infection. The prospective observational German Synagis™ Registry comprises data from 249 children below 25 months of age with DS and palivizumab prophylaxis 2009-2016 (1191 administrations; mean 4.8 per patient and season). The median gestational age and the birth weight in patients without and with DS were 31 versus 37 weeks (P < 0.001) and 1590 versus 2750 g, respectively (P < 0.001). Patients with DS significantly more often had congenital heart disease (CHD), siblings in kindergarten or school, treatment with oxygen at home, immunodeficiency, and neuromuscular impairment. The RSV-related hospitalization rate in patients with DS was 1.20%; the hospitalization rate in patients without DS was 0.71%.

CONCLUSION

Data from 249 children with DS receiving palivizumab prophylaxis in seven consecutive RSV seasons (2009-2016) in Germany reveal important differences between patients with and without DS concerning the main indication for palivizumab use and additional risk factors. Bearing in mind the limitations of an uncontrolled postmarketing observational study, the results confirm the field effectiveness of palivizumab prophylaxis in this special population. What is Known: • Recent studies describe the Down syndrome as independent risk factor for a complicated clinical course in infants with RSV infection. What is New: • Compared with other infants receiving palivizumab prophylaxis, patients with Down syndrome significantly more often had congenital heart disease, siblings in kindergarten or school, treatment with oxygen at home, immunodeficiency, and neuromuscular impairment. • In infants with palivizumab prophylaxis breakthrough, RSV-related hospitalization rates were not significantly higher in those with Down syndrome.

Dose-dependent relationships between weight status and clinical outcomes among infants hospitalized with respiratory syncytial virus infections

BACKGROUND

Associations between weight status and manifestations of respiratory syncytial virus infections remain unclear, especially in infants.

OBJECTIVE

This study investigated the dose-response relationships between weight status and clinical outcomes among infants hospitalized with respiratory syncytial virus infections.

METHODS

We obtained hospital discharge records for inpatients aged <12 months with diagnoses of bronchitis/pneumonia and respiratory syncytial virus infections, using a Japanese national inpatient database. The patients were classified into underweight, normal-weight, or overweight/obese groups using weight-for-length according to World Health Organization criteria. We compared need for intensive care, 30-day readmission, mean total hospitalization costs, and length of hospital stay across the three groups using multivariable mixed-effects regression models and restricted cubic spline functions.

RESULTS

Overall, 42 698 patients were identified, comprising 3697 underweight, 35 849 normal-weight, 3152 overweight/obese patients. The underweight group had significantly higher risk of intensive care (adjusted odds ratio, 1.35; 95% confidence interval, 1.18-1.82) and longer length of stay (adjusted difference, 0.12 days; 95% confidence interval, 0.04-0.20 days) than the normal-weight group. No significant differences in 30-day readmission or hospitalization costs were observed among the three groups. The lower and upper thresholds for a significant association between weight status and intensive care were weight-for-length z-scores of -0.64 (26th percentile) and 2.08 (98th percentile), respectively.

CONCLUSIONS

These findings demonstrate that abnormal weight status is an independent risk factor for greater illness severity among infants hospitalized with respiratory syncytial virus infections.

The burden of respiratory syncytial virus (RSV) associated acute lower respiratory infections in children with Down syndrome: A systematic review and meta-analysis

Background

Acute lower respiratory tract infections (ALRIs) caused by respiratory syncytial virus (RSV) are a leading cause of hospitalization in infants. Numerous risk factors have been identified in the aetiology of severe RSV–associated ALRI necessitating hospitalisation, including prematurity and congenital heart disease. Down syndrome (DS), a common genetic disorder associated with congenital and dysmorphic features, has recently been identified as an independent risk factor for RSV–associated ALRI requiring hospitalisation; however, the disease burden of RSV–associated ALRI in this population has not yet been established. Similarly, the impact of DS as an independent risk factor has not yet been quantified. We aimed therefore to estimate the incidence of admissions in children with DS, and by comparing this with unaffected children, to quantify the risk of DS independent of other risk factors.

Methods

A systematic review of the existing literature published between 1995 and March 1, 2017 was performed to quantify the incidence of hospitalisation due to RSV–associated ALRI in children with DS. Meta–analyses were performed on extracted data using STATA statistical software, and hospitalisation rates for children with and without DS under the age of 2 were calculated.

Findings

5 articles were ultimately deemed eligible for analyses. Analyses were limited to children under the age of 2 years. We calculated the hospitalisation rate for children with DS in this age group to be 117.6 per 1000 child–years (95% CI 67.4–205.2), vs a rate of 15.2 per 1000 child–years (95% CI 8.3–27.6) in unaffected children. This indicates DS contributes to a 6.8 (95% CI 5.5–8.4) fold increase in the relative risk of hospitalisation for RSV–associated ALRI.

Interpretation

Though limited by a small number of articles, this review found sufficient evidence to conclude DS was a significant independent risk factor for the development of severe RSV–associated ALRI requiring hospitalisation. Further studies are needed to define the impact of DS in conjunction with other comorbidities on the risk of severe RSV infection. Determining benefits of immunoprophylaxis or future vaccines against RSV in this at–risk population is warranted.

CHD and respiratory syncytial virus: global expert exchange recommendations

BACKGROUND

Palivizumab is the standard immunoprophylaxis against serious disease due to respiratory syncytial virus infection. Current evidence-based prophylaxis guidelines may not address certain children with CHD within specific high-risk groups or clinical/management settings.

METHODS

An international steering committee of clinicians with expertise in paediatric heart disease identified key questions concerning palivizumab administration; in collaboration with an additional international expert faculty, evidence-based recommendations were formulated using a quasi-Delphi consensus methodology.

RESULTS

Palivizumab prophylaxis was recommended for children with the following conditions: <2 years with unoperated haemodynamically significant CHD, who are cyanotic, who have pulmonary hypertension, or symptomatic airway abnormalities; <1 year with cardiomyopathies requiring treatment; in the 1st year of life with surgically operated CHD with haemodynamically significant residual problems or aged 1-2 years up to 6 months postoperatively; and on heart transplant waiting lists or in their 1st year after heart transplant. Unanimous consensus was not reached for use of immunoprophylaxis in children with asymptomatic CHD and other co-morbid factors such as arrhythmias, Down syndrome, or immunodeficiency, or during a nosocomial outbreak. Challenges to effective immunoprophylaxis included the following: multidisciplinary variations in identifying candidates with CHD and prophylaxis compliance; limited awareness of severe disease risks/burden; and limited knowledge of respiratory syncytial virus seasonal patterns in subtropical/tropical regions.

CONCLUSION

Evidence-based immunoprophylaxis recommendations were formulated for subgroups of children with CHD, but more data are needed to guide use in tropical/subtropical countries and in children with certain co-morbidities.

Defining the Incidence and Associated Morbidity and Mortality of Severe Respiratory Syncytial Virus Infection Among Children with Chronic Diseases

INTRODUCTION

REGAL (RSV Evidence-a Geographical Archive of the Literature) has provided a comprehensive review of the published evidence in the field of respiratory syncytial virus (RSV) in Western countries over the last 20 years. This review covers the risk and burden of RSV infection in children with underlying medical conditions or chronic diseases (excluding prematurity and congenital heart disease).

METHODS

A systematic review of publications between January 1, 1995 and December 31, 2015 across PubMed, Embase, The Cochrane Library, and Clinicaltrials.gov was supplemented by papers identified by the authors through March 2017. Studies reporting data for hospital visits/admissions for RSV infection as well as studies reporting RSV-associated morbidity and mortality were included. Study quality and strength of evidence (SOE) were graded.

RESULTS

A total of 2703 studies were identified and 58 were included. Down syndrome, irrespective of prematurity and congenital heart disease (moderate SOE), immunocompromised children (low SOE), cystic fibrosis (low SOE), and neurologic conditions (low SOE) were associated with a significantly increased risk of RSV hospitalization. A number of other congenital malformations and chronic conditions were also associated with severe RSV disease (low SOE). In general, pre-existing disease was also a predisposing factor for RSV-related mortality (low SOE).

CONCLUSION

Severe RSV infection in infants and young children with underlying medical conditions or chronic diseases poses a significant health burden. Further studies are needed to fully quantify the epidemiology, burden and outcomes in these populations, in particular RSV-attributable mortality.

Severe Respiratory Viral Infections: New Evidence and Changing Paradigms

Lower respiratory tract infection is a leading cause of death in the United States. Advances in diagnostic testing have improved our ability to detect pathogens. Viral pathogens are important causal pathogens in immunocompetent patients. As the number of elderly adults and those with chronic medical conditions increases, the burden of viral respiratory infections will increase. Clinicians must be familiar with the characteristics of rhinovirus, human adenoviruses, respiratory syncytial virus, and human metapneumovirus. Major challenges include distinguishing true infection from asymptomatic carriage and characterizing patients admitted with severe lower respiratory tract infection who do not have a causative pathogen identified.

National cohort study showed that infants with Down's syndrome faced a high risk of hospitalisation for the respiratory syncytial virus

AIM

The respiratory syncytial virus (RSV) is a leading cause of hospitalisation in infants. We investigated this risk in children with Down's syndrome under two years of age, adjusted for other known risk factors.

METHODS

This national, retrospective 1:2 matched cohort study comprised all Swedish children born with Down's from 2006 to 2011, who were each randomly matched to two controls without Down's. Data on RSV hospitalisation and risk factors for RSV were obtained from national registers. The risk of RSV hospitalisation was assessed using multivariable Cox regression with pairwise stratification.

RESULTS

The study comprised 814 children with Down's and 1628 controls. We found that 82 children with Down's (10.1%) and 22 controls (1.4%) were hospitalised for RSV. The hazard ratio for children with Down's was 4.00 (95% confidence interval 1.58-10.13) for up to one year of age and 6.60 (95% CI: 2.83-15.38) for up to two years of age, adjusted for other risk factors. During the second year of life, RSV hospitalisation continued for children with Down's, while it was minimal for the controls.

CONCLUSION

Children with Down's faced a high risk of RSV hospitalisation, which continued beyond the first year of age.

Quantitative, Phenotypical, and Functional Characterization of Cellular Immunity in Children and Adolescents With Down Syndrome

Background

Infections and autoimmune disorders are more frequent in Down syndrome, suggesting abnormality of adaptive immunity. Although the role of B cells and antibodies is well characterized, knowledge regarding T cells is limited.

Methods

Lymphocyte subpopulations of 40 children and adolescents with Down syndrome and 51 controls were quantified, and phenotype and functionality of antigen-specific effector T cells were analyzed with flow cytometry after polyclonal and pathogen-specific stimulation (with varicella-zoster virus [VZV] and cytomegalovirus [CMV]). Results were correlated with immunoglobulin (Ig) G responses.

Results

Apart from general alterations in the percentage of lymphocytes, regulatory T cells, and T-helper 1 and 17 cells, all major T-cell subpopulations showed higher expression of the inhibitory receptor PD-1. Polyclonally stimulated effector CD4+ T-cell frequencies were significantly higher in subjects with Down syndrome, whereas their inhibitory receptor expression (programmed cell death 1 [PD-1] and cytotoxic T-lymphocyte antigen 4 [CTLA-4]) was similar to that of controls and cytokine expression profiles were only marginally altered. Pathogen-specific immunity showed age-appropriate levels of endemic infection, with correlation of CMV-specific cellular and humoral immunity in all subjects. Among VZV IgG-positive individuals, a higher percentage of VZV-specific T-cell-positive subjects was seen in those with Down syndrome.

Conclusions

Despite alterations in lymphocyte subpopulations, individuals with Down syndrome can mount effector T-cell responses with similar phenotype and functionality as controls but may require higher effector T-cell frequencies to ensure pathogen control.

A Retrospective, Longitudinal, Claims-Based Comparison of Concomitant Diagnoses Between Individuals with and Without Down Syndrome

BACKGROUND

Individuals with Down syndrome (DS) experience various comorbidities in excess of the prevalence seen among the non-DS population. However, the extent of the excess burden of comorbidities specifically within commercially and publicly insured DS populations aged < 21 years is not currently known.

OBJECTIVES

To (a) describe the most common diagnoses among individuals with DS who have either commercial or Medicaid insurance and (b) compare the prevalence of those diagnoses between DS cases and non-DS controls.

METHODS

This was a longitudinal, retrospective study using health care claims of commercially insured and Medicaid-insured individuals in the Truven Health MarketScan Databases from 2008 to 2015. Individuals aged < 2, 2-5, 6-11, and 12-20 years with a DS diagnosis (cases; commercial: n = 15,948; Medicaid: n = 11,958) were matched to individuals without DS (controls; commercial: n = 47,844; Medicaid: n = 35,874) using a 1:3 ratio. The annual number of diagnoses was compared between cases and controls within age groups using t-tests, and the prevalence of the most common diagnoses was compared using chi-square tests.

RESULTS

Cases in all age groups in both databases had more diagnoses annually than controls (mean =9-17 per year vs. 4-10 per year, P < 0.001), and the number of diagnoses decreased with age for cases and controls. Among the most common case diagnoses were upper respiratory infections (28.9%-59.1% vs. 19.5%-52.9%); suppurative otitis media (25.1%-56.8% vs. 8.7%-51.2%); nutrition/metabolic/developmental symptoms (37.9%-50.4% vs. 7.7%-10.6%); delays in development (22.8%-52.8% vs. 4.1%-10.9%); and general symptoms (35.1%-47.2% vs. 22.1%-37.2%), and the prevalence of each was greater among cases versus controls in all age groups in both databases (P < 0.001). The most common diagnoses among controls included some of the same as among cases, as well as acute pharyngitis (18.7%-31.8% vs. 19.2%-30.5%); allergic rhinitis (19.9%-24.3% vs. 15.3%-20.7%); viral/chlamydial infections (24.2%-26.6% vs. 17.7%-23.5%); and joint disorders (11.6% vs. 16.6%), and most were significantly more prevalent among cases (P < 0.05).

CONCLUSIONS

Commercially insured and Medicaid-insured individuals aged < 21 years with DS experience a greater number and prevalence of concomitant diagnoses compared with non-DS individuals. Awareness of these common diagnoses could help facilitate the optimal care of these individuals by the pediatric health care community.

DISCLOSURES

This study was sponsored and funded by Genentech. Truven Health Analytics, an IBM Company, receives payment from Genentech to conduct research, including the research for this study. Truven Health Analytics also receives payment from other pharmaceutical companies to conduct research. Kong and Evans are employed by Truven Health Analytics. Csoboth is employed by Genentech. Brixner reports fees paid to the University of Utah by Truven Health Analytics on her behalf for work related to this study. Hurley reports fees from Genentech for work on this study and for work outside of this study. At the time of this study, Visootsak was employed by F. Hoffman-LaRoche Pharmaceuticals, parent company of Genentech. All authors, including those affiliated with the study sponsor, were involved in the design of the study, interpretation of the data, writing of the manuscript, and the decision to submit the manuscript for publication. Study concept and design were contributed by Kong, Hurley, and Brixner, along with Evans. Kong and Evans collected the data, and data interpretation was performed by Csoboth, Visootsak, Brixner, and Hurley, with assistance from Kong. The manuscript was written by Evans, Kong, Hurley, and Brixner and revised by Kong, Hurley, Evans, and Brixner, with assistance from Csoboth and Visootsak.

Influenza and other respiratory viruses: standardizing disease severity in surveillance and clinical trials

INTRODUCTION

Influenza-Like Illness is a leading cause of hospitalization in children. Disease burden due to influenza and other respiratory viral infections is reported on a population level, but clinical scores measuring individual changes in disease severity are urgently needed. Areas covered: We present a composite clinical score allowing individual patient data analyses of disease severity based on systematic literature review and WHO-criteria for uncomplicated and complicated disease. The 22-item ViVI Disease Severity Score showed a normal distribution in a pediatric cohort of 6073 children aged 0-18 years (mean age 3.13; S.D. 3.89; range: 0 to 18.79). Expert commentary: The ViVI Score was correlated with risk of antibiotic use as well as need for hospitalization and intensive care. The ViVI Score was used to track children with influenza, respiratory syncytial virus, human metapneumovirus, human rhinovirus, and adenovirus infections and is fully compliant with regulatory data standards. The ViVI Disease Severity Score mobile application allows physicians to measure disease severity at the point-of care thereby taking clinical trials to the next level.

Down syndrome as risk factor for respiratory syncytial virus hospitalization: A prospective multicenter epidemiological study

BACKGROUND

Respiratory syncytial virus (RSV) infection in childhood, particularly in premature infants, is associated with significant morbidity and mortality.

OBJECTIVES

To compare the hospitalization rates due to RSV infection and severity of disease between infants with and without Down syndrome (DS) born at term and without other associated risk factors for severe RSV infection.

PATIENTS/METHODS

In a prospective multicentre epidemiological study, 93 infants were included in the DS cohort and 68 matched by sex and data of birth (±1 week) and were followed up to 1 year of age and during a complete RSV season.

RESULTS

The hospitalization rate for all acute respiratory infection was significantly higher in the DS cohort than in the non-DS cohort (44.1% vs 7.7%, P<.0001). Hospitalizations due to RSV were significantly more frequent in the DH cohort than in the non-DS cohort (9.7% vs 1.5%, P=.03). RSV prophylaxis was recorded in 33 (35.5%) infants with DS. The rate of hospitalization according to presence or absence of RSV immunoprophylaxis was 3.0% vs 15%, respectively.

CONCLUSIONS

Infants with DS showed a higher rate of hospitalization due to acute lower respiratory tract infection and RSV infection compared to non-DS infants. Including DS infants in recommendations for immunoprophylaxis of RSV disease should be considered.

Down's syndrome is a risk factor for severe lower respiratory tract infection due to respiratory syncytial virus

AIM

Previous studies have suggested that Down's syndrome is an independent risk factor for severe respiratory infection due to respiratory syncytial virus (RSV). We compared the clinical characteristics of children with and without Down's syndrome hospitalised due to RSV.

METHODS

This retrospective cohort study compared data from hospitalisations due to RSV lower respiratory tract infections (LRTI) in children under 14 years of age with (n = 58) and without (n = 58) Down's syndrome.

RESULTS

The Down's group had longer hospital stays than the controls of six versus four days (p < 0.0001), even after adjusting for age, weeks of gestation at birth, presence of asthma, bronchopulmonary dysplasia, haemodynamically significant and nonsignificant congenital heart disease. This difference increased when only children under one year of age were analysed to 11 versus five days (p < 0.0001). Children with Down's syndrome were more likely to be admitted to intensive care unit (43.1% versus 22.4%, p = 0.017), need noninvasive mechanical ventilation (36.2% versus 13.7%, p = 0.005) and be prescribed antibiotics and steroids.

CONCLUSION

Children with Down's syndrome hospitalised due to RSV LRTI had longer hospital stays and worse clinical courses than controls, highlighting the need for RSV prophylaxis for children with Down's syndrome, especially under one year of age.

Intensive Care Unit Admission and Death Rates of Infants Admitted With Respiratory Syncytial Virus Lower Respiratory Tract Infection in Mexico

BACKGROUND

Respiratory syncytial virus (RSV) is the most common etiology for acute respiratory infection hospital admissions in young children. Case fatality rates for hospitalized patients range between 0% and 3.4%. Recent reports indicate that deaths associated with RSV are uncommon in developed countries. However, the role of this virus as a current cause of mortality in other countries requires further examination.

METHODS

Children with RSV infection admitted between May 2003 and December 2014 to a level 2 specialty hospital in Mexico were included in this analysis. Underlying risk factors, admission to the intensive care unit (ICU) and condition on discharge were assessed to determine the ICU admission and death rates associated to RSV infection.

RESULTS

We analyzed data of 1153 patients with RSV infection in whom information regarding underlying illnesses and discharge status was available. Sixty patients (5.2 %) were admitted to the ICU and 12 (1.04 %) died. Relevant underlying conditions were present in 320 (27.7%) patients. Infants with underlying respiratory disorders (excluding asthma) and a history of prematurity had high ICU admission rates (17.1% and 13.8%, respectively). Mortality rates were highest for infants with respiratory disease (excluding asthma) (7.3%), cardiovascular diseases (5.9%) and neurologic disorders (5.3%). The ICU admission and death rates were higher in infants <6 months of age than in other age groups.

CONCLUSIONS

The ICU admission rate and mortality rate in Mexican infants hospitalized with RSV infection were 5.2% and 1%, respectively. Mortality rates were high in infants with respiratory, cardiovascular and neurologic disorders.

Perceived Risk of Severe Respiratory Syncytial Virus Disease and Immunoprophylaxis Use Among US Pediatric Specialists

This study was conducted to assess the perception of US pediatric specialists of respiratory syncytial virus (RSV) disease risk and determine their clinical practices regarding immunoprophylaxis for high-risk children. Separate surveys were sent to neonatologists, pediatricians, pediatric pulmonologists, and pediatric cardiologists. Data were collected using structured questions requiring quantitative responses. Most neonatologists and pediatricians (>82.7%) reported a high clinical need for RSV immunoprophylaxis in preterm infants <32 weeks' gestational age. Pediatric pulmonologists and pediatric cardiologists suggested that health conditions indicative of chronic lung disease of prematurity and hemodynamically significant congenital heart disease, respectively, confer eligibility for RSV immunoprophylaxis. Agreement with the changes in the 2014 American Academy of Pediatrics guidance for RSV immunoprophylaxis was mixed among respondents from the 4 specialties. Survey findings may provide a basis to improve education about risk for severe RSV disease and evaluate changes in physician use of RSV immunoprophylaxis based on the 2014 guidance.

Trends in Respiratory Syncytial Virus and Bronchiolitis Hospitalization Rates in High-Risk Infants in a United States Nationally Representative Database, 1997-2012

BACKGROUND

Respiratory syncytial virus (RSV) causes significant pediatric morbidity and is the most common cause of bronchiolitis. Bronchiolitis hospitalizations declined among US infants from 2000‒2009; however, rates in infants at high risk for RSV have not been described. This study examined RSV and unspecified bronchiolitis (UB) hospitalization rates from 1997‒2012 among US high-risk infants.

METHODS

The Kids' Inpatient Database (KID) infant annual RSV (ICD-9 079.6, 466.11, 480.1) and UB (ICD-9 466.19, 466.1) hospitalization rates were estimated using weighted counts. Denominators were based on birth hospitalizations with conditions associated with high-risk for RSV: chronic perinatal respiratory disease (chronic lung disease [CLD]); congenital airway anomalies (CAA); congenital heart disease (CHD); Down syndrome (DS); and other genetic, metabolic, musculoskeletal, and immunodeficiency conditions. Preterm infants could not be identified. Hospitalizations were characterized by mechanical ventilation, inpatient mortality, length of stay, and total cost (2015$). Poisson and linear regression were used to test statistical significance of trends.

RESULTS

RSV and UB hospitalization rates were substantially elevated for infants with higher-risk CHD, CLD, CAA and DS without CHD compared with all infants. RSV rates declined by 47.0% in CLD and 49.7% in higher-risk CHD infants; no other declines in high-risk groups were observed. UB rates increased in all high-risk groups except for a 22.5% decrease among higher-risk CHD. Among high-risk infants, mechanical ventilation increased through 2012 to 20.4% and 13.5% of RSV and UB hospitalizations; geometric mean cost increased to $31,742 and $25,962, respectively, and RSV mortality declined to 0.9%.

CONCLUSIONS

Among high-risk infants between 1997 and 2012, RSV hospitalization rates declined among CLD and higher-risk CHD infants, coincident with widespread RSV immunoprophylaxis use in these populations. UB hospitalization rates increased in all high-risk groups except higher-risk CHD, suggesting improvement in the health status of higher-risk CHD infants, potentially due to enhanced surgical interventions. Mechanical ventilation use and RSV and UB hospitalization costs increased while RSV mortality declined.

Trends in respiratory syncytial virus bronchiolitis hospitalizations in children less than 1 year: 2004-2012

OBJECTIVE

To analyze trends in health outcomes and the influence of risk factors in children under 1 year with acute bronchiolitis due to respiratory syncytial virus (RSV bronchiolitis). A risk-adjustment model for RSV bronchiolitis in-hospital mortality was also developed.

RESEARCH DESIGN AND METHODS

Retrospective study of hospitalizations for RSV bronchiolitis in children aged <1 year from 2004 to 2012. We used nationally representative data from the Spanish National Health Service records.

RESULTS

Over the study period, the annual hospital discharges for RSV bronchiolitis ranged between 6390 and 8637. The annual in-hospital mortality rate ranged from 120 (2004) to 69 (2012) per 100,000 hospitalizations and the mean length of stay decreased steadily from 6.5 to 5.2 days (p < 0.001); 98.3% of hospitalizations for RSV bronchiolitis were children without risk factors. The in-hospital mortality rate due to RSV bronchiolitis in children with risk factors was 18.8 times higher than non-high-risk children and, in adjusted analyses, the OR of in-hospital mortality due to RSV bronchiolitis was higher than that due to other causes.

LIMITATIONS

This study is a retrospective analysis, based on administrative data. It does not include data about pre- or in-hospital treatments, and has the limitations inherent in procedures for determining risk-adjusted mortality rates. Socioeconomic and environmental factors have not been considered in this study.

CONCLUSIONS

RSV bronchiolitis is a leading cause of hospitalizations for infants under 1 year and has not shown incidence reduction over a 9 year period. Risk factors increase the in-hospital mortality risk and it is higher if the hospitalization cause is RSV bronchiolitis than any other reason.

Healthy Late-preterm infants born 33-36+6 weeks gestational age have higher risk for respiratory syncytial virus hospitalization

BACKGROUND

Respiratory syncytial virus (RSV) is a leading cause of hospitalization for children <1year old and is more severe in premature infants.

OBJECTIVE

To assess whether late preterm (LPT) birth is an independent risk factor for RSV hospitalization and more severe RSV disease in children less than 24months old.

METHODS

We conducted a retrospective cohort study of children enrolled in the military health system. LPT birth was defined as 33+0 through 36+6weeks gestation. Patients who received palivizumab or had known risk factors for RSV were excluded. Adjusted hazard ratios (HR) for LPT birth were calculated using a Cox proportional hazard model, while controlling for sex and RSV season. Severity of illness was assessed by comparing the need for respiratory support, length of stay, and age at RSV hospitalization between LPT and term children.

RESULTS

A total of 599,535 children for 1,216,382 person-years were studied, of which 7597 children were admitted for RSV infection. LPT infants accounted for 643 (8.5%) of these RSV hospitalizations. The incidence density for RSV hospitalization of LPT infants was higher than term children (12.1 vs 7.8 per 1000 person-years). LPT infants had an increased adjusted risk for RSV hospitalization; specifically, those born 33+0 through 34+6weeks (HR 2.45; 95% confidence interval (CI) 1.96-3.07), and 35+0 through 36+6weeks (HR, 1.92; 95% CI, 1.66-2.22). LPT infants had longer hospital stays and required more respiratory support than term children.

CONCLUSIONS

LPT birth is an independent risk factor for severe RSV disease and need for hospitalization.