Community-acquired respiratory infections in young children with congenital heart diseases in the palivizumab era: the Spanish 4-season civic epidemiologic study

Twenty-five years of palivizumab: a global historic review of its impact on the burden of respiratory syncytial virus disease in children

INTRODUCTION

Respiratory syncytial virus (RSV) causes significant morbidity and mortality in young children. For 25 years, palivizumab has been the only effective pharmaceutical RSV preventive.

AREAS COVERED

We summarize the development and a quarter-century of real-world evidence with palivizumab. We highlight its positive impact on the burden of RSV in high-risk children. Based on lessons learnt from its implementation, we suggest strategies for effective and equitable deployment of newer RSV preventives.

EXPERT OPINION

Following failure of the formalin-inactivated RSV vaccine in 1967, RSV intravenous immunoglobulin was approved in 1996 after three decades' research. Subsequently, palivizumab emerged as the most effective and safe RSV preventive, demonstrated by the IMpact trial, and was licensed in 1998 in the United States. Over the last 25 years, the benefits of palivizumab have been firmly established through a wealth of evidence, predominantly from high-income countries (HICs). To achieve a global impact with the newer RSV preventives, evidenced-based universal guidelines must be developed and endorsed by regulatory authorities and relevant scientific societies. Independent economic evaluations should incorporate all RSV-associated healthcare costs, reduction of long-term respiratory sequelae, and standardized outcomes. Most importantly, equity in product availability and implementation, particularly in low- and middle-income countries (LMICs) is essential.

Analysis of risk factors for prolonged stay in the intensive care unit after cardiac surgery in children with pneumonia

AIM

Preoperative pneumonia in children with CHD may lead to longer stays in the ICU after surgery. However, research on the associated risk factors is limited. This study aims to evaluate the pre-, intra-, and postoperative risk factors contributing to extended ICU stays in these children.

METHODS

This retrospective cohort study collected data from 496 children with CHD complicated by preoperative pneumonia who underwent cardiac surgery following medical treatment at a single centre from 2017 to 2022. We compared the clinical outcomes of patients with varying ICU stays and utilised multivariate logistic regression analysis and multiple linear regression analyses to evaluate the risk factors for prolonged ICU stays.

RESULTS

The median ICU stay for the 496 children was 7 days. Bacterial infection, severe pneumonia, and Risk Adjustment for Congenital Heart Surgery-1 were independent risk factors for prolonged ICU stays following cardiac surgery (P < 0.05).

CONCLUSION

CHD complicated by pneumonia presents a significant treatment challenge. Better identification of the risk factors associated with long-term postoperative ICU stays in these children, along with timely diagnosis and treatment of respiratory infections in high-risk populations, can effectively reduce ICU stays and improve resource utilisation.

Prevalence of immunological aberrations and 22q11.2 deletion in children with conotruncal anomalies: A cross-sectional study

Introduction

22q11.2 deletion is associated with conotruncal anomalies and immunological aberrations. Given the common embryonic origin of conotruncus and thymus, conotruncal anomalies may be associated with immunological aberrations irrespective of 22q11.2 deletion. We planned to study the prevalence of immunological aberrations and 22q11.2 deletion among patients with conotruncal anomaly to understand the impact of their interplay.

Patients and Methods

Preoperative children (age <12 years) with conotruncal anomalies were evaluated for clinical dysmorphism, lymphocyte subsets by flowcytometry, immunoglobulin levels by nephelometry, and 22q11.2 deletion by multiplex ligand-dependent probe amplification (January 2021-June 2022). Patients with asplenia and polysplenia were excluded from immunological studies.

Results

Major cardiac defects ([n = 101], [median age, 32 days]) included dextro-transposition of great arteries (d-TGA) - 41.6%, tetralogy of Fallot - 37.6%, double outlet right ventricle (DORV) - 13.9%, and truncus arteriosus - 4.9%. Four patients had polysplenia with situs inversus, while 17 had clinical dysmorphism. Flow cytometry (n = 82) revealed low absolute counts of lymphocytes (33%), T-cells (51.2%), CD4+ cells (50%), and CD8+ cells (51.2%), while only 14.1% had low IgG levels. Eight patients (8/95, 8.4%) had 22q11.2 deletion, with universal deletion of TBX1-2 and TBX1-7 genes; the other 19 genes were deleted in various combinations. Two patients with 22q11.2 deletion had normal T-cell subsets, while none had a complete absence of T-cells.

Conclusion

Immunological aberrations, especially T-cell abnormalities, were present in almost half of the patients, irrespective of 22q11.2 deletion. Only 8.4% of patients had 22q11.2 deletion. The high incidence of d-TGA among 22q11.2 deletion patients needs further exploration.

An epidemiological investigation of high-risk infants for Respiratory Syncytial Virus infections: a retrospective cohort study

BACKGROUND

Respiratory Syncytial Virus (RSV) infections may lead to severe consequences in infants born preterm with breathing problems (such as bronchopulmonary dysplasia (BPD) and respiratory distress syndrome (RDS)) or congenital heart diseases (CHD). Since studies investigating the influence of different gestational age (WGA) and concomitant specific comorbidities on the burden of RSV infections are scarce, the present study aimed to better characterize these high-risk populations in the Italian context.

METHODS

This retrospective, longitudinal and record-linkage cohort study involved infants born between 2017 and 2019 in Lazio Region (Italy) and is based on data extracted from administrative databases. Each infant was exclusively included in one of the following cohorts: (1) BPD-RDS (WGA ≤35 with or without CHD) or (2) CHD (without BPD and/or RDS) or (3) Preterm (WGA ≤35 without BPD (and/or RDS) or CHD). Each cohort was followed for 12 months from birth. Information related to sociodemographic at birth, and RSV and Undetermined Respiratory Agents (URA) hospitalizations and drug consumption at follow-up were retrieved and described.

RESULTS

A total of 8,196 infants were selected and classified as 1,084 BPD-RDS, 3,286 CHD and 3,826 Preterm. More than 30% of the BPD-RDS cohort was composed by early preterm infants (WGA ≤ 29) in contrast to the Preterm cohort predominantly constitute by moderate preterm infants (98.2%), while CHD infants were primarily born at term (83.9%). At follow-up, despite the cohorts showed similar proportions of RSV hospitalizations, in BPD-RDS cohort hospitalizations were more frequently severe compared to those occurred in the Preterm cohort (p<0.01), in the BPD-RDS cohort was also found the highest proportion of URA hospitalizations (p<0.0001). In addition, BPD-RDS infants, compared to those of the remaining cohorts, received more frequently prophylaxis with palivizumab (p<0.0001) and were more frequently treated with adrenergics inhalants, and glucocorticoids for systemic use.

CONCLUSIONS

The assessment of the study clinical outcomes highlighted that, the demographic and clinical characteristics at birth of the study cohorts influence their level of vulnerability to RSV and URA infections. As such, continuous monitoring of these populations is necessary in order to ensure a timely organization of health care system able to respond to their needs in the future.

Prophylaxis protects infants with congenital heart disease from severe forms of RSV infection: an Italian observational retrospective study : Palivizumab prophylaxis in children with congenital heart disease

BACKGROUND

In children with congenital heart disease (CHD) respiratory syncytial virus (RSV) infection may have a severe course, with increased risk of morbidity and mortality, requiring hospital admission and intensive care. The aim of the present study was to evaluate the effect of prophylaxis with palivizumab in preventing RSV-associated hospitalization in infants with CHD.

METHODS

We carried out an observational, retrospective study in a paediatric cardiology division at a secondary-care centre in Italy, extracting from the database children with CHD who, from November 2004 to March 2022, matched the criteria for palivizumab prophylaxis, to evaluate the hospitalization rate in CHD patients with and without palivizumab prophylaxis and their RSV-related hospitalization characteristics compared with a group of children without CHD and no other underlying clinical conditions (control group, CG), hospitalized for RSV infection.

RESULTS

One hundred twenty-eight children with CHD were enrolled in the study, mainly (71.9%) with increased pulmonary flow, and received palivizumab prophylaxis. Twenty-seven received hospital care for bronchiolitis. Almost all CHD patients hospitalized for bronchiolitis (26 out of 27) received partial prophylaxis (≤ 3 doses). CHD patients with bronchiolitis stay longer in the hospital than control (14.4 ± 21.7 days vs 6.2 ± 2.3 days) some of which require intensive care (n = 4).

CONCLUSIONS

Our study provides evidence of the efficacy of palivizumab in protecting patients with hemodynamically significant CHD under the age of 2 years from RSV disease and its life-threatening complications. Reducing hospitalisation rate, morbidity, and mortality in this category of patients, passive immune prophylaxis with palivizumab may impact healthcare resource availability and utilisation.

Challenges in the prevention or treatment of RSV with emerging new agents in children from low- and middle-income countries

INTRODUCTION

Respiratory syncytial virus (RSV) causes approximately 120,000 deaths annually in children <5 years, with 99% of fatalities occurring in low- and middle-income countries (LMICs).

AREAS COVERED

There are numerous RSV interventions in development, including long-acting monoclonal antibodies, vaccines (maternal and child) and treatments which are expected to become available soon. We reviewed the key challenges and issues that need to be addressed to maximize the impact of these interventions in LMICs. The epidemiology of RSV in LMICs was reviewed (PubMed search to 30 June 2020 inclusive) and the need for more and better-quality data, encompassing hospital admissions, community contacts, and longer-term respiratory morbidity, emphasized. The requirement for an agreed clinical definition of RSV lower respiratory tract infection was proposed. The pros and cons of the new RSV interventions are reviewed from the perspective of LMICs.

EXPERT OPINION

We believe that a vaccine (or combination of vaccines, if practicable) is the only viable solution to the burden of RSV in LMICs. A coordinated program, analogous to that with polio, involving governments, non-governmental organizations, the World Health Organization, the manufacturers and the healthcare community is required to realize the full potential of vaccine(s) and end the devastation of RSV in LMICs.

Impact of pulmonary hypertension and congenital heart disease with hemodynamic repercussion on the severity of acute respiratory infections in children under 5 years of age at a pediatric referral center in Colombia, South America

BACKGROUND

Acute respiratory infection is one of the main causes of morbidity in children. Some studies have suggested that pulmonary hypertension and congenital heart disease with haemodynamic repercussion increase the severity of respiratory infections, but there are few publications in developing countries.

METHODS

This was a prospective cohort study evaluating the impact of pulmonary hypertension and congenital heart disease (CHD) with haemodynamic repercussion as predictors of severity in children under 5 years of age hospitalised for acute respiratory infection.

RESULTS

Altogether, 217 children hospitalised for a respiratory infection who underwent an echocardiogram were evaluated; 62 children were diagnosed with CHD with haemodynamic repercussion or pulmonary hypertension. Independent predictors of admission to intensive care included: pulmonary hypertension (RR 2.14; 95% CI 1.06-4.35, p = 0.034), respiratory syncytial virus (RR 2.52; 95% CI 1.29-4.92, p = 0.006), and bacterial pneumonia (RR 3.09; 95% CI 1.65-5.81, p = 0.000). A significant difference was found in average length of hospital stay in children with the cardiovascular conditions studied (p = 0.000).

CONCLUSIONS

Pulmonary hypertension and CHD with haemodynamic repercussion as well as respiratory syncytial virus and bacterial pneumonia were predictors of severity in children with respiratory infections in this study. Early recognition of cardiovascular risks in paediatric populations is necessary to lessen the impact on respiratory infections.

Burden of Respiratory Syncytial Virus Disease and Mortality Risk Factors in Argentina: 18 Years of Active Surveillance in a Children's Hospital

BACKGROUND

Respiratory syncytial virus is the leading cause of acute lower respiratory infection in children. We aimed to describe the clinical-epidemiologic pattern and risk factors for mortality associated with RSV infection.

METHODS

This is a prospective, cross-sectional study of acute lower respiratory infection in children admitted to the Children's Hospital during 2000 to 2017. Viral diagnosis was made by fluorescent antibody techniques or real-time-polymerase chain reaction. We compared clinical-epidemiologic characteristics of RSV infection in nonfatal versus fatal cases. Multiple logistic regression was used to identify independent predictors of mortality.

RESULTS

Of 15,451 patients with acute lower respiratory infection, 13,033 were tested for respiratory viruses and 5831 (45%) were positive: RSV 81.3% (4738), influenza 7.6% (440), parainfluenza 6.9% (402) and adenovirus 4.3% (251). RSV had a seasonal epidemic pattern coinciding with months of lowest average temperature. RSV cases show a case fatality rate of 1.7% (82/4687). Fatal cases had a higher proportion of prematurity (P < 0.01), perinatal respiratory history (P < 0.01), malnourishment (P < 0.01), congenital heart disease (P < 0.01), chronic neurologic disease (P < 0.01) and pneumonia at clinical presentation (P = 0.014). No significant difference between genders was observed. Most deaths occurred among children who had complications: respiratory distress (80.5%), nosocomial infections (45.7%), sepsis (31.7%) and atelectasis (13.4%). Independent predictors of RSV mortality were moderate-to-severe malnourishment, odds ratio (OR): 3.69 [95% confidence interval (CI): 1.98-6.87; P < 0.0001]; chronic neurologic disease, OR: 4.14 (95% CI: 2.12-8.08; P < 0.0001); congenital heart disease, OR: 4.18 (95% CI: 2.39-7.32; P< 0.0001); and the age less than 6 months, OR: 1.99 (95% CI: 1.24-3.18; P = 0.004).

CONCLUSIONS

RSV showed an epidemic pattern affecting mostly young children. Malnourishment, chronic neurologic disease, congenital heart disease and the age less than 6 months were the independent risk factors for RSV mortality.

Comprehensive Management Considerations of Select Noncardiac Organ Systems in the Cardiac Intensive Care Unit

As the acuity and complexity of pediatric patients with congenital cardiac disease have increased, there are many noncardiac issues that may be present in these patients. These noncardiac problems may affect clinical outcomes in the cardiac intensive care unit and must be recognized and managed. The Pediatric Cardiac Intensive Care Society sought to provide an expert review of some of the most common challenges of the respiratory, gastrointestinal, hematological, renal, and endocrine systems in pediatric cardiac patients. This review provides a brief overview of literature available and common practices.

Respiratory syncytial virus prophylaxis and the "special population"

Bronchiolitis is the most frequent airway infection in the first 2 years of life, and the respiratory syncytial virus (RSV) is the most frequently responsible virus. In selected high-risk groups, RSV may cause severe respiratory disease leading to hospitalization, need for mechanical ventilation, and even death. These high-risk groups include children with congenital heart disease, infants with neuromuscular impairment, cystic fibrosis, Down Syndrome, immunodeficiency syndromes and others specific conditions. In these high-risk populations defined in literature as "special population", a 3- to 10-fold increase in the rate of RSV hospitalization has been observed, justifying RSV specific prophylaxis with palivizumab, a monoclonal antibody that binds a viral glycoprotein epitope and blocks the link between RSV and target cell. Evidence of safety and efficacy of RSV prophylaxis in these populations is lacking. Given the low incidence of these conditions, randomized clinical trials are not feasible. The purpose of this paper is to give an update from the literature of various conditions at higher risk to develop severe RSV infection, and to offer an overview of the efficacy of palivizumab in preventing RSV infection in these specific populations.

Respiratory virus prophylaxis in congenital heart disease

Respiratory syncytial virus (RSV) is the leading cause of acute lower respiratory tract infections and causes up to 200,000 infant deaths a year worldwide. The average rate of hospitalization for severe RSV infection is 5 per 1000 children, and the rate is three-times higher in those with congenital heart disease (CHD). Palivizumab, a monoclonal antibody, reduces hospitalization rates and intensive care admissions. It is used prophylactically and is administered as monthly doses during the RSV season. Hemodynamically unstable CHD is the most susceptible CHD to a severe episode of RSV infection. This review explores current evidence surrounding therapies, patterns of infection and identifies groups which may still be vulnerable to severe RSV infection.

Past, Present and Future Approaches to the Prevention and Treatment of Respiratory Syncytial Virus Infection in Children

INTRODUCTION

The REGAL (RSV Evidence - A Geographical Archive of the Literature) series 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 seventh and final publication covers the past, present and future approaches to the prevention and treatment of RSV infection among infants and children.

METHODS

A systematic review was undertaken of publications between January 1, 1995 and December 31, 2017 across PubMed, Embase and The Cochrane Library. Studies reporting data on the effectiveness and tolerability of prophylactic and therapeutic agents for RSV infection were included. Study quality and strength of evidence (SOE) were graded using recognized criteria. A further nonsystematic search of the published literature and Clinicaltrials.gov on antiviral therapies and RSV vaccines currently in development was also undertaken.

RESULTS

The systematic review identified 1441 studies of which 161 were included. Management of RSV remains centered around prophylaxis with the monoclonal antibody palivizumab, which has proven effective in reducing RSV hospitalization (RSVH) in preterm infants < 36 weeks' gestational age (72% reduction), children with bronchopulmonary dysplasia (65% reduction), and infants with hemodynamically significant congenital heart disease (53% reduction) (high SOE). Palivizumab has also shown to be effective in reducing recurrent wheezing following RSVH (high SOE). Treatment of RSV with ribavirin has conflicting success (moderate SOE). Antibodies with increased potency and extended half-life are currently entering phase 3 trials. There are approximately 15 RSV vaccines in clinical development targeting the infant directly or indirectly via the mother.

CONCLUSION

Palivizumab remains the only product licensed for RSV prophylaxis, and only available for high-risk infants. For the general population, there are several promising vaccines and monoclonal antibodies in various stages of clinical development, with the aim to significantly reduce the global healthcare impact of this common viral infection.

FUNDING

AbbVie.

Palivizumab in the prevention of severe respiratory syncytial virus infection in children with congenital heart disease; a novel cost-utility modeling study reflecting evidence-based clinical pathways in Spain

BACKGROUND

Respiratory syncytial virus (RSV) infection remains one of the major reasons of re-hospitalization among children with congenital heart disease (CHD). This study estimated the cost-effectiveness of palivizumab prophylaxis versus placebo, in Spain, from the societal perspective, using a novel cost-effectiveness model reflecting evidence-based clinical pathways.

METHODS

A decision-analytic model, combining a decision tree structure in the first year and a Markov structure in later years, was constructed to evaluate the benefits and costs associated with palivizumab versus no prophylaxis among children with CHD. In the first year of the model, children were at risk of mild (i.e. medically attended, MA-RSV) and severe (hospitalized, RSV-H) RSV infection. The impact of delayed corrective CHD surgery due to RSV infection and the consequence of performed surgery despite severe infection were considered. In later years, patients were at risk of developing asthma and allergic sensitization as sequelae of RSV infection. Input data for the model were derived from the pivotal clinical trial and systematic literature reviews. Indirect costs included parental absence from work and nosocomial infections. In agreement with Spanish guidelines, costs and effects were discounted at 3%.

RESULTS

Over a lifetime horizon, palivizumab prophylaxis yielded 0.11 and 0.07 additional quality-adjusted life years (QALYs) and life years (LYs), respectively, at additional costs of € 1,693, resulting in an ICER of € 15,748 per QALY gained and € 24,936 per LY gained. Probabilistic sensitivity analyses demonstrated that the probability of palivizumab prophylaxis being cost-effective at a € 30,000 per QALY threshold was 92.7%. The ICER remained below this threshold for most extreme scenario analyses.

CONCLUSIONS

The model demonstrated that palivizumab prophylaxis results in more QALYs than no prophylaxis in children with CHD. Palivizumab prophylaxis was shown to be a cost-effective health care intervention according to the commonly accepted standards of cost-effectiveness in Spain (ICER below the threshold of € 30,000 per QALY).

Perioperative infections in congenital heart disease

BACKGROUND

Perioperative infections have significant consequences for children with congenital heart disease (CHD), which can manifest as acute or chronic infection followed by poor growth and progressive cardiac failure. The consequences include delayed or higher-risk surgery, and increased postoperative morbidity and mortality.

METHODS

A systematic search for studies evaluating the burden and interventions to reduce perioperative infections in children with CHD was undertaken using PubMed.

RESULTS

Limited studies conducted in low- to middle-income countries demonstrated the large burden of perioperative infections among children with CHD. Most studies focussed on infections after surgery. Few studies evaluated strategies to prevent preoperative infection or the impact of infection on decision-making around the timing of surgery. Children with CHD have multiple risk factors for infections including delayed presentation, inadequate treatment of cardiac failure, and poor nutrition.

CONCLUSIONS

The burden of perioperative infections is high among children with CHD, and studies evaluating the effectiveness of interventions to reduce these infections are lacking. As good nutrition, early corrective surgery, and measures to reduce nosocomial infection are likely to play a role, practical steps can be taken to make surgery safer.

The respiratory system in pediatric chronic heart disease

Cardiovascular disease in the pediatric population closely affects the respiratory system inducing water retention in the lungs and pulmonary edema, airway compression by cardiovascular structures, restrictive pulmonary physiology as a result of hemodynamic changes and surgical repair, susceptibility to respiratory infections, development of pulmonary hypertension, thrombosis, or hemorrhage. Chronic heart failure and congenital heart disease are characterized by various respiratory manifestations and symptoms mimicking lung disease, which are frequently difficult to diagnose and treat. Pulmonary function is multiply affected in pediatric heart disease with mostly restrictive but also obstructive and diffusion abnormalities. Patients with Fontan circulation represent a separate group with slow, passive pulmonary blood flow and distinct pathophysiology with low cardiac output heart failure, restrictive lung pattern, increased thromboembolic complications and rare conditions such as protein losing enteropathy and plastic bronchitis. Distinguishing between cardiovascular and pulmonary symptoms may be challenging in the growing population of pediatric and adult survivors of congenital heart disease and understanding of the relationship of the two systems in heart disease is crucial for the optimal management of these patients.

Defining the Risk and Associated Morbidity and Mortality of Severe Respiratory Syncytial Virus Infection Among Infants with Congenital Heart Disease

Introduction

The REGAL (RSV Evidence—a Geographical Archive of the Literature) series provide a comprehensive review of the published evidence in the field of respiratory syncytial virus (RSV) in Western countries over the last 20 years. This fourth publication covers the risk and burden of RSV infection in infants with congenital heart disease (CHD).

Methods

A systematic review was undertaken for articles published between January 1, 1995 and December 31, 2015 across PubMed, Embase, The Cochrane Library, and Clinicaltrials.gov. Studies reporting data for hospital visits/admissions for RSV infection among children with CHD as well as studies reporting RSV-associated morbidity, mortality, and healthcare costs were included. The focus was on children not receiving RSV prophylaxis. Study quality and strength of evidence (SOE) were graded using recognized criteria.

Results

A total of 1325 studies were identified of which 38 were included. CHD, in particular hemodynamically significant CHD, is an independent predictor for RSV hospitalization (RSVH) (high SOE). RSVH rates were generally high in young children (<4 years) with CHD (various classifications), varying between 14 and 357/1000 (high SOE). Children (<6 years) with RSV infection spent 4.4–14 days in hospital, with up to 53% requiring intensive care (high SOE). Infants (<2 years) with CHD had a more severe course of RSVH than those without CHD (high SOE). Case fatality rates of up to 3% were associated with RSV infection in children with CHD (high SOE). RSV infection in the perioperative period of corrective surgery and nosocomial RSV infection in intensive care units also represent important causes of morbidity (moderate SOE).

Conclusion

CHD poses a significant risk for RSVH and subsequent morbidity and mortality. RSV infection often complicates corrective heart surgery. To reduce the burden and improve outcomes, further research and specific studies are needed to determine the longer-term effects of severe RSV infection in young children with CHD.

Electronic supplementary material

The online version of this article (doi:10.1007/s40121-016-0142-x) contains supplementary material, which is available to authorized users.

Retrospective Multicenter Study of Respiratory Syncytial Virus Prophylaxis in Korean Children with Congenital Heart Diseases

BACKGROUND AND OBJECTIVES

We conducted a review of current data on respiratory syncytial virus (RSV) prophylaxis with palivizumab, in Korean children with congenital heart diseases (CHD). In 2009, the Korean guideline for RSV prophylaxis had established up to five shots monthly per RSV season, only for children <1 year of age with hemodynamic significance CHD (HS-CHD).

SUBJECTS AND METHODS

During the RSV seasons in 2009-2015, we performed a retrospective review of data for 466 infants with CHD, examined at six centers in Korea.

RESULTS

Infants received an average of 3.7±1.9 (range, 1-10) injections during the RSV season. Fifty-seven HS-CHD patients (12.2%) were hospitalized with breakthrough RSV bronchiolitis, with a recurrence in three patients, one year after the initial check-up. Among patients with simple CHD, only five (1.1%) patients received one additional dose postoperatively, as per the limitations set by the Korean guideline. Among the 30 deaths (6.4%), five (1.1%) were attributed to RSV infection; three to simple CHD, one to Tetralogy of Fallot, and one to hypertrophic cardiomyopathy (HCM). Of the three HCM patients that exceeded guidelines for RSV prophylaxis, two (66.6%) were hospitalized, and one died of RSV infection (33.3%).

CONCLUSION

In accordance to the Korean guideline, minimal injections of palivizumab were administered to patients having HS-CHD <one year of age during the RSV season; the risk of RSV infection remains significant among children with simple CHD, cardiomyopathy, and children above the age of one year with HS-CHD.

Respiratory syncytial virus-associated hospitalizations over three consecutive seasons in children with congenital heart disease

The purpose of this investigation was to analyze the burden of respiratory syncytial virus (RSV)-related hospitalizations in infants and children with congenital heart disease (CHD) over three consecutive RSV seasons. Retrospectively, all children with hemodynamically significant (HS-CHD) and not significant (HNS-CHD) CHD born between 2004 and 2008 at a tertiary care university hospital and identified by ICD-10 diagnoses were included. Data on RSV-related hospitalizations over the first three years of life covering at least three RSV seasons (November-April) were analyzed. The overall incidence of RSV-related hospitalization was 9.6 % (58/602), without a statistically significant difference between HS-CHD and HNS-CHD (7.3 % vs. 10.4 %; p = 0.258). Recommendation of palivizumab prophylaxis did not influence the RSV hospitalization rates between groups. Patients with HS-CHD and early surgery were significantly less often hospitalized due to RSV compared to those with delayed surgery (1.3 % vs. 14.3 %; p = 0.003). The median duration of hospitalization was 8.5 days (HS-CHD: 14 vs.

HNS-CHD

7 days; p = 0.003). Thirteen patients (22.4 %) were admitted to the intensive care unit (ICU), for a median of 10 days. The median age at admission was 2 months, with a significant difference between HS-CHD and HNS-CHD (6 vs. 2 months; p = 0.001). The majority (97 %) of RSV-related hospitalizations occurred before 12 months of age. Patients with HS-CHD had a significantly more severe course of RSV disease and were older at the time of hospitalization. Early surgery seemed to significantly reduce the risk of RSV hospitalization during the first RSV season.

Efficacy of palivizumab prophylaxis among infants with congenital heart disease: A case control study

BACKGROUND

Palivizumab prophylaxis for RSV has been consistently reported to reduce the risk of hospital admissions related to RSV infection in children with symptomatic cardiac disease. This study was designed to investigate the efficacy of palivizumab prophylaxis among infants with congenital heart disease (CHD) in Turkey.

METHODS

A total of 91 infants with CHD who received palivizumab prophylaxis and 96 infants with CHD without prophylaxis (0-12 months:52; 12-24 months:44) were included in this single-center retrospective case control study. Data on patient characteristics, household environment, and LRTIs were evaluated.

RESULTS

In patients without prophylaxis, the rate of overall lower respiratory tract infections (LRTIs) (P < 0.001), complicated LRTIs (P = 0.006), LRTI-related hospitalization (P < 0.001) and ICU admission (P = 0.008) were significantly higher than control patients. Weight <10th percentile (odds ratio (OR) 5.78, 95% confidence interval (CI):1.37; 24.4, P < 0.001) and concomitant chromosome abnormality (OR 4.01, 95% CI:1.01;16.45, P < 0.001) in patients with prophylaxis, while presence of a sibling <11 years of age (OR 3.38, 95% CI: 1.21; 9.46, P < 0.001) and congestive heart failure (OR 8.63, 95% CI: 2.81; 26.6, P < 0.001) in the control group were the significant correlates of LRTI-related hospitalization.

CONCLUSION

Our findings revealed significantly lower rate of overall and complicated LRTIs, LRTI-related hospitalization and ICU admissions in infants with CHD via palivizumab prophylaxis.

Preventing hospitalizations for respiratory syncytial virus infection

Respiratory syncytial virus infection is the leading cause of lower respiratory tract infections in young children. Palivizumab has minimal impact on RSV hospitilization rates as it is only practical to offer it to the highest risk groups. The present statement reviews the published literature and provides updated recommendations regarding palivizumab use in children in Canada.

Respiratory Syncytial Virus Bronchiolitis in Children up to 5 Years of Age in Spain: Epidemiology and Comorbidities: An Observational Study

This epidemiological survey in Spain estimates the burden of respiratory syncytial virus (RSV) infection in children up to 5 year of age during a 15-year period (1997-2011). Observational retrospective survey was conducted by reviewing data of the National Surveillance System for Hospital Data, including >98% of Spanish hospitals. All hospitalizations related to RSV infection for children up to 5 years, reported during 1997-2011 period, were analyzed. Codes were selected by using the International Classification of Diseases 9th Clinical Modification 466.0-466.19, 480.1, and 079.6. A total of 326,175 and 286,007 hospital discharges for children up to 5 and 2 years of age were reported during the study period. The annual incidence was 1072 and 2413 patients per 100,000, respectively. The average length of hospital stay was 5.7 (standard deviation 8.2) days. Four hundred forty-six deaths were reported; of those, 403 occurred in children <2 years and 355 (80%) occurred in children <12 months of age. Hospitalization and mortality rates were significantly higher in boys and decrease significantly with age. The higher rate of hospitalization and mortality rates were found in the first year of life. Annual average cost for National Health Care System was € 47 M with a mean hospitalization cost of €2162. The average length of hospitalization and costs were significantly higher in high-risk children. RSV infections in children up to 5 year of age still pose a significant health threat in Spain, especially in the infants. The development of preventive, diagnostic, and therapeutic guidelines focused in children with comorbidities may help reduce the hospital and economic burden of the disease.

[Application of molecular assay for adenovirus detection among different pediatric patients]

OBJECTIVE:

Adenoviruses play an important role in the etiology of severe acute lower respiratory infection, especially in young children. The aim of the present study was to evaluate the Human Adenovirus (HAdV) detection by different methods (Direct Fluorescence Assay DFA and Nested Polymerase Chain Reaction nested PCR), among samples collected from different groups of pediatric patients.

METHODS:

Collection of samples was made in children with congenital heart disease (CHD 123 nasal aspirates collected in the years of 2005, 2007 and 2008) and in community children (CC 165 nasal aspirates collected in 2008). Children were eligible if they presented acute respiratory infection (ARI) of probable viral etiology, within up to 7 days of symptoms' onset. All studied samples were evaluated by DFA and nested PCR assay.

RESULTS:

Of the 290 samples included during the study period, 43 (14.8%) were positive on at least one test: 17/165 (10.3%) of the CC and 26/125 (20.8%) of the CHD children. The nested PCR detection rates in the community children were 15/165 (9.1%), and for children with CHD, 24/125 (19.2%). Molecular method showed higher detection rates when compared to the DFA test (p<0.001). Univariate analysis showed that children with congenital heart disease presented a significantly higher chance for acquiring the HAdV (Odds Ratio 2.3; 95% CI: 1.18-4.43).

CONCLUSIONS:

Based on data obtained in the present evaluation, we suggest that a routine surveillance should be performed in high risk patients by molecular methods, thus improving diagnostic flow and efficiency.

Social, economic, and health impact of the respiratory syncytial virus: a systematic search

BACKGROUND

Bronchiolitis caused by the respiratory syncytial virus (RSV) and its related complications are common in infants born prematurely, with severe congenital heart disease, or bronchopulmonary dysplasia, as well as in immunosuppressed infants. There is a rich literature on the different aspects of RSV infection with a focus, for the most part, on specific risk populations. However, there is a need for a systematic global analysis of the impact of RSV infection in terms of use of resources and health impact on both children and adults. With this aim, we performed a systematic search of scientific evidence on the social, economic, and health impact of RSV infection.

METHODS

A systematic search of the following databases was performed: MEDLINE, EMBASE, Spanish Medical Index, MEDES-MEDicina in Spanish, Cochrane Plus Library, and Google without time limits. We selected 421 abstracts based on the 6,598 articles identified. From these abstracts, 4 RSV experts selected the most relevant articles. They selected 65 articles. After reading the full articles, 23 of their references were also selected. Finally, one more article found through a literature information alert system was included.

RESULTS

The information collected was summarized and organized into the following topics: 1. Impact on health (infections and respiratory complications, mid- to long-term lung function decline, recurrent wheezing, asthma, other complications such as otitis and rhino-conjunctivitis, and mortality; 2. Impact on resources (visits to primary care and specialists offices, emergency room visits, hospital admissions, ICU admissions, diagnostic tests, and treatments); 3. Impact on costs (direct and indirect costs); 4. Impact on quality of life; and 5. Strategies to reduce the impact (interventions on social and hygienic factors and prophylactic treatments).

CONCLUSIONS

We concluded that 1. The health impact of RSV infection is relevant and goes beyond the acute episode phase; 2. The health impact of RSV infection on children is much better documented than the impact on adults; 3. Further research is needed on mid- and long-term impact of RSV infection on the adult population, especially those at high-risk; 4. There is a need for interventions aimed at reducing the impact of RSV infection by targeting health education, information, and prophylaxis in high-risk populations.

Estimating intracardiac and extracardiac shunting in the setting of complex congenital heart disease

Complex congenital heart disease (CHD) is associated with significant morbidity worldwide. Managing hypoxemia in these populations can be difficult, particularly in the setting of cyanotic CHD. However, the presence of additional extracardiac shunts secondary to acute respiratory disease can be very challenging to manage. Before understanding how to deal with hypoxemia in patients with dual shunts, one needs to understand the physiology and diagnosis related to the individual shunts and apply this knowledge to the patient as a whole.

Respiratory syncytial virus prophylaxis in children with cardiac disease: a retrospective single-centre study

OBJECTIVES

To examine the characteristics of congenital heart disease patients hospitalised with respiratory syncytial virus infection after prophylaxis and determine the associated comorbidities and the incidence of breakthrough respiratory syncytial virus infections.

STUDY DESIGN

This is a retrospective, single-centre study that was conducted over a period of 7 years. Respiratory syncytial virus infection was identified by classification codes and confirmed by virological tests. Data on baseline demographics, cardiac anomalies, other underlying disease, criteria for hospitalisation, type of respiratory illness and management, complications, and palivizumab prophylaxis were analysed by standard descriptive methods and comparative statistics.

RESULTS

A total of 30 patients were enrolled. The majority were ≤ 2 years (n = 24). The mean admission age was 15.1 months (standard deviation = 18.3). In all, 90% were acyanotic, 40% had haemodynamically significant disease, and 60% had ≥ 1 underlying medical illness. Patients were admitted with: respiratory distress (86.7%), hypoxaemia (66.7%), fever (60%), inability to maintain oral intake (36.7%), and apnoea (16.7%). More than 50% required mechanical ventilation and intensive care with a median stay of 11 days (range: 1-43); the length of hospital stay for all children was 10 days (range: 1-65). Complications included: concurrent bacterial sepsis (20%), electrolyte abnormalities (16.7%), and worsening pulmonary hypertension (13.3%). Of 10 infants ≤ 2 years with haemodynamically significant heart disease, four had received prophylaxis. There was one death, which was attributed to respiratory syncytial virus infection.

CONCLUSIONS

Overall, 185 infants ≤ 2 years with haemodynamically significant cardiac disease received prophylaxis. In all, six qualifying infants missed immunisation and were hospitalised. Breakthrough respiratory syncytial virus infections occurred in 2.2%, demonstrating good efficacy of palivizumab in this population compared with the original, multi-centre, randomised trial.

Epidemiology and risk factors for severe respiratory syncytial virus infections requiring pediatric intensive care admission in Hong Kong children

PURPOSE

Respiratory syncytial virus (RSV) is a common cause of lower respiratory tract infection in young children. However, there are limited data on severe RSV infection requiring pediatric intensive care unit (PICU) admission. This retrospective study described features of RSV-associated PICU admissions in Hong Kong and investigated factors for mortality and duration of PICU stay.

METHODS

Children with laboratory-confirmed RSV infection and admitted to the PICUs of all eight government hospitals in Hong Kong between January 2009 and June 2011 were identified from computerized auditing systems and PICU databases. RSV in respiratory samples was detected by direct immunofluorescence and/or viral culture. The relationships between mortality and PICU duration and demographic and clinical factors were analyzed.

RESULTS

A total of 118 (2.4 %) PICU admissions were identified among 4,912 RSV-positive pediatric cases in all hospitals. Sixty-five (55.6 %) patients were infants. PICU admissions were higher between October and March. Eight (6.8 %) patients died, but only two were infants. RSV-associated mortality was related to prior sick contact, presence of older siblings, neurodevelopmental conditions, chromosomal and genetic diseases, and bacterial co-infections, but none was significant following logistic regression analyses (odds ratio 9.36, 95 % confidence interval 0.91-96.03 for prior sick contact, p = 0.060). Chronic lung disease was the only risk factor for the duration of PICU admission (β = 0.218, p = 0.017).

CONCLUSIONS

The majority of RSV-infected children do not require PICU support. There is winter seasonality for RSV-associated PICU admission in Hong Kong. Prior sick contact is the only risk factor for RSV-associated mortality, whereas the presence of chronic lung disease is associated with longer PICU stay. The current risk-based approach of RSV prophylaxis may not be effective in reducing severe RSV infections.

Recurrent lower respiratory tract infections in children: a practical approach to diagnosis

Many children are affected by recurrent lower respiratory tract infections (LRTIs), but the majority of them do not suffer from serious lung or extrapulmonary disease. The challenge for clinicians is to distinguish the recurrent RTIs with self-limiting or minor problems from those with underlying disease. The aim of this review is to describe a practical approach to children with recurrent LRTIs that limits unnecessary, expensive and time-consuming investigations. The children can be divided into three groups on the basis of their personal and family history and clinical findings: 1) otherwise healthy children who do not need further investigations; 2) those with risk factors for respiratory infections for whom a wait-and-see approach can be recommended; and 3) those in whom further investigations are mandatory. However, regardless of the origin of the recurrent LRTIs, it is important to remember that prevention by means of vaccines against respiratory pathogens (i.e. type b Haemophilus influenzae, pertussis, pneumococcal and influenza vaccines) can play a key role.

Early repair of large infant ventricular septal defect despite respiratory syncytial virus-induced respiratory failure with postrepair chylous pericardial effusion requiring pleuropericardial window: a case report and review of the literature

The surgical correction of congenital cardiac lesions that are complicated by intercurrent respiratory syncytial virus (RSV) pneumonitis has traditionally been deferred for at least 6 to 8 weeks. The presumption is that using cardiopulmonary bypass will increase the risk of postoperative pulmonary complications. We present an infant who developed acute respiratory failure related to RSV pneumonitis and required urgent mechanical ventilation. Cardiac evaluation revealed a large nonrestrictive ventricular septal defect (VSD), aortic arch hypoplasia, normally functioning bicuspid aortic valve, and hemodynamic instability associated with markedly increased pulmonary blood flow. Separation from mechanical ventilation was unsuccessful preoperatively. He underwent VSD repair with cardiopulmonary bypass less than 4 weeks after initial RSV infection. He was extubated successfully within 72 hours of VSD repair. Approximately 6 weeks postoperatively, he developed a circumferential chylous pericardial effusion of unclear etiology--an exceedingly rare complication of VSD repair in early infancy in a non-Down syndrome patient. The chylous effusion was initially managed unsuccessfully with Portogen/Monogen and a percutaneously placed pericardial drain. Two weeks later, he underwent creation of a pleuropericardial window with successful resolution of the chylous effusion. It is of interest to pediatricians to be able to correctly time the repair of congenital heart disease lesions after RSV infection to minimize post-bypass pulmonary complications and yet avoid morbidity from undue delays in repair. In addition, chylopericardium can occur in infants after VSD repair, and dietary modification and catheter drainage may not be adequate.

Pulmonary complications of congenital heart disease

Cardiac and pulmonary pathophysiologies are closely interdependent, which makes the management of patients with congenital heart disease (CHD) all the more complex. Pulmonary complications of CHD can be structural due to compression causing airway malacia or atelectasis of the lung. Surgical repair of CHD can also result in structural trauma to the respiratory system, e.g., chylothorax, subglottic stenosis, or diaphragmatic paralysis. Disruption of the Starling forces in the pulmonary vascular system in certain types of CHD lead to alveolar-capillary membrane damage and pulmonary oedema. This in turn results in poorly compliant lungs with a restrictive lung function pattern that can deteriorate to cause hypoxemia. The circulation post single ventricle palliative surgery (the so called "Fontan circulation") poses a unique spectrum of pulmonary pathophysiology with restrictive lung function and a low pulmonary blood flow state that predisposes to thromboembolic complications and plastic bronchitis. As the population of patients surviving post CHD repair increases, the incidence of pulmonary complications has also increased and presents a unique cohort in both the paediatric and adult clinics.

Managing the morbidity associated with respiratory viral infections in children with congenital heart disease

Children with congenital heart disease (CHD) are at risk for increased morbidity from viral lower respiratory tract infections because of anatomical cardiac lesions than can worsen an already compromised respiratory status. Respiratory syncytial virus (RSV) remains an important pathogen in contributing toward the morbidity in this population. Although the acute treatment of RSV largely remains supportive, the development of monoclonal antibodies, such as palivuzumab, has reduced the RSV-related hospitalization rate in children with CHD. This review highlights the specific cardiac complications of RSV infection, the acute treatment of bronchiolitis in patients with CHD, and the search for new therapies against RSV, including an effective vaccine, because of the high cost associated with immunoprophylaxis and its lack of reducing RSV-related mortality.