Association Between Estimated Cumulative Vaccine Antigen Exposure Through the First 23 Months of Life and Non-Vaccine-Targeted Infections From 24 Through 47 Months of Age.

Importance: Some parents are concerned that multiple vaccines in early childhood could weaken their child's immune system. Biological data suggest that increased vaccine antigen exposure could increase the risk for infections not targeted by vaccines. Objective: To examine estimated cumulative vaccine antigen exposure through the first 23 months of life in children with and without non-vaccine-targeted infections from 24 through 47 months of age. Design, Setting, and Participants: A nested case-control study was conducted in 6 US health care organizations participating in the Vaccine Safety Datalink. Cases were identified by International Classification of Diseases codes for infectious diseases in the emergency department and inpatient medical settings and then validated by medical record review. Cases of non-vaccine-targeted infection were matched to controls by age, sex, health care organization site, and chronic disease status. Participants were children ages 24 through 47 months, born between January 1, 2003, and September 31, 2013, followed up until December 31, 2015. Exposures: Cumulative vaccine antigen exposure, estimated by summing the number of antigens in each vaccine dose received from birth through age 23 months. Main Outcomes and Measures: Non-vaccine-targeted infections, including upper and lower respiratory infections and gastrointestinal infections, from 24 through 47 months of age, and the association between these infections and estimated cumulative vaccine exposure from birth through 23 months. Conditional logistic regression was used to estimate matched odds ratios representing the odds of non-vaccine-targeted infections for every 30-unit increase in estimated cumulative number of antigens received. Results: Among the 944 patients (193 cases and 751 controls), the mean (SD) age was 32.5 (6.3) months, 422 (45%) were female, and 61 (7%) had a complex chronic condition. Through the first 23 months, the estimated mean (SD) cumulative vaccine antigen exposure was 240.6 (48.3) for cases and 242.9 (51.1) for controls. The between-group difference for estimated cumulative antigen exposure was -2.3 (95% CI, -10.1 to 5.4; P = .55). Among children with vs without non-vaccine-targeted infections from 24 through 47 months of age, the matched odds ratio for estimated cumulative antigen exposure through age 23 months was not significant (matched odds ratio, 0.94; 95% CI, 0.84 to 1.07). Conclusions and Relevance: Among children from 24 through 47 months of age with emergency department and inpatient visits for infectious diseases not targeted by vaccines, compared with children without such visits, there was no significant difference in estimated cumulative vaccine antigen exposure through the first 23 months of life.

Fifteen-minute consultation: structured approach to management of a child with recurrent croup.

Recurrent croup is a distinct clinical entity from viral croup. It is not a specific diagnosis and its presence should alert the clinician to explore the underlying cause. We discuss an evidence-based structured approach to management of a child with recurrent croup.

Outdoor Cold Air Versus Room Temperature Exposure for Croup Symptoms: A Randomized Controlled Trial.

OBJECTIVES: Croup is the most common cause of acute upper airway obstruction in children. The benefits of treating croup with steroids are well established, with an onset of effect 30 minutes after administration. We investigated whether a 30-minute exposure to outdoor cold air might improve mild to moderate croup symptoms before the onset of action of steroids. METHODS: This open-label, single-center, randomized controlled trial, enrolled children aged 3 months to 10 years with croup and a Westley Croup Score (WCS) ≥2 attending a tertiary pediatric emergency department. Participants were randomized (1:1) to either a 30-minute exposure to outdoor cold (<10°C) atmospheric air or to indoor ambient room air immediately after triage and administration of a single-dose oral dexamethasone. The primary endpoint was a decrease in WCS ≥2 points from baseline at 30 minutes. Analyses were intention to treat. RESULTS: A total of 118 participants were randomly assigned to be exposed to outdoor cold air (n = 59) or indoor room temperature (n = 59). Twenty-nine of 59 children (49.2%) in the outdoor group and 14 of 59 (23.7%) in the indoor group showed a decrease in WCS ≥2 points from baseline at 30 minutes after triage (risk difference 25.4% [95% confidence interval 7.0-43.9], P = .007). Patients with moderate croup benefited the most from the intervention at 30 minutes (risk difference 46.1% [20.6-71.5], P < .001). CONCLUSIONS: A 30-minute exposure to outdoor cold air (<10°C), as an adjunct to oral dexamethasone, is beneficial for reducing the intensity of clinical symptoms in children with croup, especially when moderate.

Croup: an overview.

Croup is a common illness responsible for up to 15 percent of emergency department visits due to respiratory disease in children in the United States. Croup symptoms usually start like an upper respiratory tract infection, with low-grade fever and coryza followed by a barking cough and various degrees of respiratory distress. In most children, the symptoms subside quickly with resolution of the cough within two days. Croup is often caused by viruses, with parainfluenza virus (types 1 to 3) as the most common. However, physicians should consider other diagnoses, including bacterial tracheitis, epiglottitis, foreign body aspiration, peritonsillar abscess, retropharyngeal abscess, and angioedema. Humidification therapy has not been proven beneficial. A single dose of dexamethasone (0.15 to 0.60 mg per kg usually given orally) is recommended in all patients with croup, including those with mild disease. Nebulized epinephrine is an accepted treatment in patients with moderate to severe croup. Most episodes of croup are mild, with only 1 to 8 percent of patients with croup requiring hospital admission and less than 3 percent of admitted patients requiring intubation.

The Relationship between Croup and Gastroesophageal Reflux: A Systematic Review and Meta-Analysis.

OBJECTIVE: The mechanism by which recurrent croup occurs is unknown. Gastroesophageal reflux is commonly implicated, although this relationship is only loosely documented. We conducted a systematic review with a meta-analysis component to evaluate the relationship between recurrent croup and gastroesophageal reflux disease (GERD), and to assess for evidence of improvement in croup symptoms when treated. STYLE DESIGN: Systematic Review and Meta Analysis. METHODS: We searched five separate databases. Studies were included if they discussed the relationship between croup and GERD in children, >5 subjects, and available in English. Literature retrieved was assessed according to pre-specified criteria. Retrieved articles were reviewed by two independent authors and decisions mediated by a third author. If there was a difference of opinion after first review, a second review was performed to obtain consensus. Heterogeneity was calculated and summarized in forest plots. RESULTS: Of 346 initial records, 15 met inclusion criteria. These were two retrospective cohort and 13 cross-sectional studies. Thirteen of 15 articles support an association between recurrent croup and GERD. Although heterogeneity is high among studies that reported prevalence of GERD, there is less uncertainty in results for improvement to recurrent croup after GERD treatment. Most studies lacked a control group and all carry a moderate-to-high risk of bias. CONCLUSION: There is limited evidence linking GERD to recurrent croup; Further research is needed to assess for causality as most studies are retrospective, lack a control group, and have a study design exposing them to bias. Patients treated with reflux medication appear to demonstrate a reduced incidence of croup symptoms. LEVEL OF EVIDENCE: 1 Laryngoscope, 131:209-217, 2021.

A Curious Case of Croup: Laryngotracheitis Caused by COVID-19.

We describe a case of croup in a 14-month-old boy caused by severe acute respiratory syndrome coronavirus 2, the virus that causes coronavirus disease 2019. The patient presented with classic signs and symptoms consistent with croup. Workup was remarkable for a positive point-of-care test for severe acute respiratory syndrome coronavirus 2. This case represents recognition of a new clinical entity caused by coronavirus disease 2019.

Balloon dilation for recurrent stenosis after pediatric laryngotracheoplasty.

OBJECTIVES: We assessed the safety and efficacy of balloon dilation as treatment for recurrent stenosis after pediatric laryngotracheoplasty. METHODS: We studied a retrospective case series at an academic tertiary care children's hospital. We included all patients under the age of 18 years with subglottic or tracheal stenosis treated at our institution with balloon dilation between June 2007 and April 2009. The records were analyzed for patient demographics, presenting symptoms, surgical technique, and airway description. The outcome measures were airway diameter, postoperative symptoms, tracheotomy status, and complications. RESULTS: Ten patients (9 with subglottic stenosis and 1 with tracheal stenosis) underwent 20 balloon dilation procedures without complication. The average age at the time of the procedure was 17 months (range, 3 months to 9 years). The patient presenting symptoms were stridor in 7 cases and tracheotomy in 3 cases. Vascular balloons (diameter range, 6 to 12 mm; length, 20 mm) were inflated to 10 to 12 cm H2O pressure for an average of 40 seconds (range, 10 to 120 seconds). Each procedure consisted of 1 to 3 dilation cycles. The immediate postdilation airway area increased by an average factor of 4.9 (range, 1.9 to 9). Six patients had repeat procedures with an average interval between dilations of 67 days (range, 6 to 337 days). Stridor was eliminated or greatly improved in all patients on the first postoperative day; 7 patients sustained this benefit, with an average follow-up time of 10 months (range, 4 to 23 months). Six of the 10 patients had undergone previous laryngeal reconstruction (age range, 3 months to 4 years). Of these 6, 3 have no tracheotomy, with a mean follow-up of 12.5 months. The 3 children who benefited the least from dilation were noted to have more diffuse and chronic inflammation of the larynx in comparison to the responders. CONCLUSIONS: This case series suggests that balloon dilation is a relatively safe and effective procedure. It may be particularly well suited to recent stenosis after laryngotracheal reconstruction.

A simple case of a small elbow effusion.

An 11-month-old child presented with what initially appeared to be 2 simple problems, a small elbow effusion followed 1 week later by croup. This case history is presented to remind emergency medicine physicians of the importance of index of suspicion and recognition of the difference between common events occurring in a normal host versus common events occurring in an abnormal host.

Bridging bronchus (pseudocarina) and left pulmonary artery sling: A case report and literature review.

Congenital airway malformations can present with respiratory distress, cyanosis, and difficulty feeding in the neonate or infant. Clinical presentation may vary from asymptomatic to fatal airway obstruction. They may exist in isolation or in association with vascular rings and slings, bronchopulmonary malformations, and/or syndromes. We present an unusual case of bridging bronchus, complete bronchial rings, and left pulmonary artery sling presenting with recurrent croup, highlighting the importance of bronchoscopy and CT imaging to achieve an accurate diagnosis in patients with recurrent croup and/or respiratory failure not responding to usual treatment measures and a multidisciplinary treatment approach.

Risk factors for croup in children with recurrent respiratory infections: a case-control study.

Croup accounts for approximately 15% of all lower respiratory disease in children, but little is known about risk factors or its recurrence rate. The aim of this study was to determine the risk factors for croup and recurrent croup and to find out whether it is possible to predict the course of the disease. We considered croup patients who visited the Paediatric Department of Oulu University Hospital as primary health care patients at night during 1996-2000. For most analyses we used sex- and age-matched control patients who had had other respiratory infection but for environmental factors we used population controls. We performed conditional logistic regression analysis on data applying to 182 pairs of patients and controls. The recurrence rate was high, as 61% of the croup patients had had at least three episodes. Family history of croup was the most significant risk factor for both croup itself and recurrent croup. In multivariable analysis the odds ratio (OR) for the parents having a history of croup was 3.2 (95% CI 1.5, 7.1, P < 0.01) and 4.1 (95% CI 1.4, 11.7, P < 0.01) for recurrent croup. Parental smoking appeared to be a risk factor for respiratory infections but not for croup. Patients with croup had a cat as a pet less often than the controls, with OR 0.5 (95% CI 0.2, 1.0, P = 0.04). Family history appeared to be an exceptionally strong predictive factor for croup and its recurrence. In this patient series prone to respiratory infections recurrence of croup was common.

Utility of bronchoscopy for recurrent croup.

OBJECTIVES: We performed a retrospective review to determine the utility of bronchoscopy in patients with recurrent croup (RC). METHODS: Bronchoscopy was performed on 30 patients with a diagnosis of RC (age, 14 months to 13.9 years) over a 2-year period. RESULTS: One third of the patients (33.3%) were found to have airway disorders, including subglottic stenosis (7), subglottic edema (2), and a subglottic cyst (1). Patients with RC who were less than 3 years of age were more likely to have an airway abnormality found on endoscopy (9 of 14 or 64.2%) than were those older than 3 years (1 of 16 or 6.2%; chi2 p < 0.001). There was no statistically significant difference in abnormal findings 1) in patients with RC who had a history of prematurity or prior intubations (chi2, p = 0.17 and p = 0.052, respectively); 2) between infectious and spasmodic croup (chi2, p = 0.794); or 3) by number of croup episodes (chi2, p = 0.300). Two patients required surgical intervention (laryngotracheal reconstruction and marsupialization of a subglottic cyst). CONCLUSIONS: Of 30 patients who underwent bronchoscopy for RC, 33% had airway disorders--mostly children less than 3 years old. We suggest a higher index of suspicion for finding airway disorders in children less than 3 years old with RC and having a lower threshold for performing diagnostic bronchoscopy in this population.

Defining atypical croup: A case report and review of the literature.

BACKGROUND: Croup is a common respiratory illness in children. It presents with a barky cough, stridor and hoarseness occurring secondary to inflammation of the subglottis and larynx. The clinical course of croup is well-described, however atypical presentations pose a diagnostic and management challenge. OBJECTIVES: This case report and systematic review aims to synthesize the published literature on the definition, diagnosis and treatment of atypical croup. STUDY SELECTION: Peer-reviewed journal publications in Ovid MEDLINE® and EMBASE from inception to January 1, 2019 in English, focusing on pediatric patients (<18 years of age) with diagnoses of atypical croup. DATA EXTRACTION: Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: Twelve studies involving 670 patients ranging from 6 months to 11 years of age presenting with atypical croup were selected. A variety of definitions of atypical croup were identified based on recurrence, duration of symptoms, severity, and etiology. Data on the incidence of atypical croup, the overall rates of intubation and tracheostomy, and patient characteristics leading to definitive airway management were not clearly characterized. LIMITATIONS: All studies were case series, case reports or retrospective chart reviews. CONCLUSIONS: Atypical croup is a poorly defined clinical entity that is used to describe recurrent, refractory, or croup-like illness that follows an uncharacteristic natural history. Our case presentation and accompanying literature review highlights the variable, but limited, information available on the diagnosis of atypical croup. Given the commonality of its use in clinical practice, we propose some guidelines around the use of the term 'atypical croup' as well as a management algorithm.

Acute subglottic laryngitis. Etiology, epidemiology, pathogenesis and clinical picture.

In about 3% of children, viral infections of the airways that develop in early childhood lead to narrowing of the laryngeal lumen in the subglottic region resulting in symptoms such as hoarseness, abarking cough, stridor, and dyspnea. These infections may eventually cause respiratory failure. The disease is often called acute subglottic laryngitis (ASL). Terms such as pseudocroup, croup syndrome, acute obstructive laryngitis and spasmodic croup are used interchangeably when referencing this disease. Although the differential diagnosis should include other rare diseases such as epiglottitis, diphtheria, fibrinous laryngitis and bacterial tracheobronchitis, the diagnosis of ASL should always be made on the basis of clinical criteria.

Uncommon presentation of a common disease: influenza A presenting as adult croup .

An 88-year-old woman presented to our emergency room with complaints of fever, coryza, barking cough and generalised fatigue for 2 days. Physical examination showed stridor, tachypnoea with use of accessory muscles of respiration on admission. Laboratory tests were unremarkable except for monocytosis with a normal total white cell count. Rapid influenza diagnostic test was positive for influenza A. Chest X-ray showed subglottic narrowing of the trachea suggestive of steeple sign. A diagnosis of influenza A-induced croup was made. She was given humidified oxygen, nebulised racemic epinephrine, intravenous dexamethasone and oseltamivir. Stridor resolved within minutes of giving nebulised epinephrine. Work of breathing improved within 4-6 hours. She was discharged 2 days later on a tapering dose of steroids.

Subglottic acute lymphoblastic leukaemia.

Acute lymphoblastic leukaemia (ALL) is one of the the most common malignancies of childhood and can occasionally present as acute airway obstruction. We present the unusual case of a 1-year-old boy who was referred to our Paediatric Otolaryngology (ENT) clinic with a recurrent history of croup. This is the first reported case of localised ALL presenting as a subglottic mass in a paediatric patient. It highlights the need to have a broader differential diagnosis in children presenting with 'recurrent croup' including extramedullary presentation of leukaemia and to have a low threshold for performing endoscopy in such cases.

Tracheostomy in human immuno-deficiency virus infected children at the Red Cross War Memorial Children's Hospital, Cape Town, South Africa.

UNLABELLED: Tracheostomy in adults with HIV/AIDS has been reported to be associated with both high and early mortality of 47-100%. There is minimal data regarding the role of tracheostomy in HIV infected children. We did a retrospective analysis of HIV positive children that underwent tracheostomy at our institution over a 5-year period, 2002-2006. A total of 70 tracheostomies were done during the period and 15 (21.4%) of these children were confirmed as HIV infected. The average age at presentation for HIV infected children with upper airway obstruction resulting eventually in tracheostomy was 9.4 months and 60% were under 1 year of age. Only three (20%) were on Anti-Retroviral Therapy (ART) prior to presentation. The cause of upper airway obstruction was croup in 14 (93%) of these 15 children. Following tracheostomy all were treated with ART. To date six children have been successfully decannulated (40%) and there have been three deaths (20%) which were unrelated to tracheostomy. CONCLUSION: Tracheostomy in HIV positive children is not associated with the high mortality that has been reported in adults provided such children are started on treatment with antiretroviral therapy.