Dominant negative variants in IKZF2 cause ICHAD syndrome, a new disorder characterised by immunodysregulation, craniofacial anomalies, hearing impairment, athelia and developmental delay.

BACKGROUND: Helios (encoded by IKZF2), a member of the Ikaros family of transcription factors, is a zinc finger protein involved in embryogenesis and immune function. Although predominantly recognised for its role in the development and function of T lymphocytes, particularly the CD4+ regulatory T cells (Tregs), the expression and function of Helios extends beyond the immune system. During embryogenesis, Helios is expressed in a wide range of tissues, making genetic variants that disrupt the function of Helios strong candidates for causing widespread immune-related and developmental abnormalities in humans. METHODS: We performed detailed phenotypic, genomic and functional investigations on two unrelated individuals with a phenotype of immune dysregulation combined with syndromic features including craniofacial differences, sensorineural hearing loss and congenital abnormalities. RESULTS: Genome sequencing revealed de novo heterozygous variants that alter the critical DNA-binding zinc fingers (ZFs) of Helios. Proband 1 had a tandem duplication of ZFs 2 and 3 in the DNA-binding domain of Helios (p.Gly136_Ser191dup) and Proband 2 had a missense variant impacting one of the key residues for specific base recognition and DNA interaction in ZF2 of Helios (p.Gly153Arg). Functional studies confirmed that both these variant proteins are expressed and that they interfere with the ability of the wild-type Helios protein to perform its canonical function-repressing IL2 transcription activity-in a dominant negative manner. CONCLUSION: This study is the first to describe dominant negative IKZF2 variants. These variants cause a novel genetic syndrome characterised by immunodysregulation, craniofacial anomalies, hearing impairment, athelia and developmental delay.

The management of very mild and mild asthma in preschoolers, children, and adolescents.

This practice point summarizes recommendations from the Canadian Thoracic Society's 2021 "Guideline update: Diagnosis and management of asthma in preschoolers, children, and adults." New recommendations include: a decrease in the frequency of daytime symptoms and reliever use to ≤2 per week in the asthma control criteria; assessing for risk of asthma exacerbation; not using as-needed short-acting beta-agonists alone in patients at higher risk for exacerbation; and the option of as-needed budesonide/formoterol (bud/form) in those ≥12 years old if they are unable to take daily inhaled corticosteroids despite extensive asthma education and support. The preference for daily inhaled corticosteroids to manage mild asthma in children, and the recommendation against intermittent short courses of inhaled corticosteroids, are unchanged.

La prise en charge de l'asthme léger et très léger chez les enfants d'âge préscolaire, les enfants et les adolescents.

Le présent point de pratique résume la mise à jour des lignes directrices de la Société canadienne de thoracologie publiée en 2021 sur le diagnostic et la prise en charge de l'asthme chez les enfants d'âge préscolaire, les enfants et les adultes. Ces nouvelles recommandations incluent, parmi les critères de contrôle de l'asthme, une diminution de la fréquence des symptômes diurnes et de l'utilisation de médicaments pour soulager l'asthme à un maximum de deux fois par semaine. Elles comprennent également l'évaluation du risque d'exacerbation de l'asthme, la non-utilisation de bêta-agonistes à courte durée d'action seuls au besoin chez les patients à plus fort risque d'exacerbation et la possibilité d'administrer du budésonide-formotérol au besoin aux jeunes de 12 ans ou plus qui sont incapables de prendre des corticostéroïdes inhalés au quotidien malgré une éducation sur l'asthme et un soutien importants. La préférence pour la prise quotidienne de corticostéroïdes inhalés afin de traiter l'asthme léger chez les enfants et la recommandation d'éviter les courts traitements intermittents de corticostéroïdes inhalés ne changent pas.

Individualized treatment strategies and considerations in patients with mild asthma: Discussion of Canadian Thoracic Society guideline recommendations.

OBJECTIVE: To highlight recommendations from the Canadian Thoracic Society (CTS) 2021 asthma guideline for adults and children aged 12 years and older and to address controversies related to the update. SOURCES OF INFORMATION: The CTS 2021 asthma guideline. MAIN MESSAGE: Asthma is a common condition encountered in primary care. Poor symptom control and exacerbations contribute substantially to the burden of disease. Practice guidelines have been shifting in recent years toward more aggressive treatment of very mild and mild asthma, with goals of optimizing symptom control and reducing exacerbations. Consider underlying risk of exacerbation, extent of asthma symptoms, adherence levels, and treatment cost when choosing therapy for patients with very mild and mild asthma. CONCLUSION: The goal of this article is to briefly review the evidence and rationale behind treatment options in the CTS guideline to help physicians make patient-centred decisions.

Impact of Perinatal Exposure to SARS-CoV-2 Infection on Early Health Outcomes among Infants Born from 2020 to 2021 in British Columbia, Canada.

Background: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has impacted healthcare services and outcomes. We aimed to investigate healthcare resource utilization and early health outcomes of infants born to mothers with perinatal SARS-CoV-2 infection. Methods: The study included all infants born alive between February 1, 2020, and April 30, 2021, in British Columbia. We used linked provincial population-based databases including data on COVID-19 testing, birth, and health information for up to one year from birth. Perinatal COVID-19 exposure for infants was defined being born to mothers with a positive test for SARS-CoV-2 infection during pregnancy or at delivery. Cases of COVID-19-exposed infants were matched with up to four non-exposed infants by birth month, sex, birthplace, and gestational age in weeks. Outcomes included hospitalizations, emergency department visits, and in-/outpatient diagnoses. Outcomes were compared between groups using conditional logistic regression and linear mixed effects models including effect modification by maternal residence. Results: Among 52,711 live births, 484 infants had perinatal exposure to SARS-CoV-2, an incidence rate of 9.18 per 1000 live births. Exposed infants (54.6% male) had a mean gestational age of 38.5 weeks, and 99% were born in hospital. Proportions of infants requiring at least one hospitalization (8.1% vs. 5.1%) and at least one emergency department visit (16.9% vs. 12.9%) were higher among the exposed vs. unexposed infants, respectively. Among infants from the urban area, those with exposure were more likely to have respiratory infectious diseases (odds ratio: 1.74; 95% confidence intervals: 1.07, 2.84), compared with those without exposure. Interpretation. In our cohort, infants born to mothers with SARS-CoV-2 infection have increased healthcare demands in their early infancy, which warrants further investigation.

Stratégies thérapeutiques individualisées et facteurs à considérer chez les patients atteints d'asthme léger: Discussion sur les recommandations des lignes directrices de la Société canadienne de thoracologie.

OBJECTIF: Mettre en valeur les recommandations des lignes directrices de 2021 de la Société canadienne de thoracologie (SCT) pour les adultes et les enfants de 12 ans et plus, et aborder les controverses entourant leur actualisation. SOURCES DE L'INFORMATION: Les lignes directrices de 2021 de la SCT sur l'asthme. MESSAGE PRINCIPAL: L'asthme est un problème souvent rencontré en soins primaires. Un mauvais contrôle des symptômes et les exacerbations contribuent considérablement à la morbidité. Au cours des dernières années, les lignes directrices de pratique clinique ont eu tendance à préconiser un traitement plus intense de l'asthme très léger et léger dans le but d'optimiser la maîtrise des symptômes et de réduire les exacerbations. Il faut tenir compte du risque d'exacerbations, de l'ampleur des symptômes d'asthme, des degrés d'adhésion et du coût du traitement dans le choix d'une thérapie pour les patients atteints d'un asthme très léger et léger. CONCLUSION: Cet article a pour but de passer brièvement en revue les données probantes et les justifications qui sous-tendent les options de traitement dans les lignes directrices de la SCT, pour aider les médecins à prendre des décisions centrées sur le patient.

FOXP1 haploinsufficiency: Phenotypes beyond behavior and intellectual disability?

The forkhead box (FOX) transcription factors have roles in development, carcinogenesis, metabolism, and immunity. In humans FOXP1 mutations have been associated with language and speech defects, intellectual disability, autism spectrum disorder, facial dysmorphisms, and congenital anomalies of the kidney and urinary tract. In mice, Foxp1 plays critical roles in development of the spinal motor neurons, lymphocytes, cardiomyocytes, foregut, and skeleton. We hypothesized therefore that mutations of FOXP1 affect additional tissues in some humans. Supporting this hypothesis, we describe two individuals with novel variants of FOXP1 (NM_032682.5:c.975-2A>C and NM_032682.5:c.1574G>A) and additional features. One had a lung disease resembling neuroendocrine cell hyperplasia of infancy (NEHI), and the second had a skeletal disorder with undertubulation of the long bones and relapsing-remitting fevers associated with flushing and edema. Although attribution of these traits to mutation of FOXP1 requires ascertainment of additional patients, we hypothesize that the variable expression of these additional features might arise by means of stochastic developmental variation.

Treatment of Pulmonary Exacerbations Improves Short But Not Long-Term Growth Trajectory in Children With Cystic Fibrosis.

OBJECTIVES: The present study sought to determine the long-term growth consequences after a pulmonary exacerbation in children with cystic fibrosis (CF). METHODS: Retrospective cohort study of pediatric patients with CF with a hospital admission for a pulmonary exacerbation. Logistic regression used to determine risk factors for failure to recover baseline body mass index (BMI) percentile. RESULTS: Of 72 patients, 43% failed to recover their baseline BMI percentile 12 months after discharge and these patients also had a lower forced expiratory volume in 1 second at follow-up. A greater decrease in weight percentile from baseline to admission was the only risk factor identified (odds ratio 0.83, P = 0.0015). CONCLUSIONS: Greater decrease in weight percentile from baseline to admission predicts failure to recover BMI percentile 1 year after a pulmonary exacerbation. Children with CF with poor growth preceding a pulmonary exacerbation continue to be at risk for long-term nutritional failure despite treatment for pulmonary exacerbation.

Bleomycin-associated Lung Toxicity in Childhood Cancer Survivors.

Pulmonary disease is a significant morbidity among childhood cancer survivors. The aim of this study was to characterize the pulmonary dysfunction experienced by childhood cancer survivors treated with bleomycin. A cross-sectional analysis of pulmonary function testing (PFT) in survivors treated with bleomycin was preformed. The most recent posttherapy PFT was assessed. Spirometry and lung volumes were categorized as normal, restrictive, obstructive, or mixed. Diffusing capacity of carbon monoxide (DLCO) was categorized as normal or abnormal. PFT data of 143 survivors was analyzed. PFTs were performed a median of 2.3 years (interquartile range, 1.4 to 4.9) from completion of therapy. Spirometry was abnormal in 58 (41%), only 5 (9%) had respiratory symptoms. Forty-two (70%) had obstructive, 11 (18%) restrictive, and 5 (9%) mixed ventilatory defects. The majority of abnormalities were mild (91%). DLCO was abnormal in 27. Reductions were mild in 96%. Patients with a history of relapse were more likely to develop abnormalities in spirometry and/or DLCO (odds ratio=5.02, 95% confidence interval: 1.3-19.4, P=0.01; odds ratio=3.47, 95% confidence interval: 1.01-11.9, P=0.03). Asymptomatic abnormalities of PFT are common among childhood cancer survivors treated with bleomycin and associated with a history of relapse. Research studying the risk for clinical progression of this dysfunction is warranted.

Diagnosis and management of asthma in preschoolers: A Canadian Thoracic Society and Canadian Paediatric Society position paper.

Asthma often starts before six years of age. However, there remains uncertainty as to when and how a preschool-age child with symptoms suggestive of asthma can be diagnosed with this condition. This delays treatment and contributes to both short- and long-term morbidity. Members of the Canadian Thoracic Society Asthma Clinical Assembly partnered with the Canadian Paediatric Society to develop a joint working group with the mandate to develop a position paper on the diagnosis and management of asthma in preschoolers. In the absence of lung function tests, the diagnosis of asthma should be considered in children one to five years of age with frequent (≥8 days/month) asthma-like symptoms or recurrent (≥2) exacerbations (episodes with asthma-like signs). The diagnosis requires the objective document of signs or convincing parent-reported symptoms of airflow obstruction (improvement in these signs or symptoms with asthma therapy), and no clinical suspicion of an alternative diagnosis. The characteristic feature of airflow obstruction is wheezing, commonly accompanied by difficulty breathing and cough. Reversibility with asthma medications is defined as direct observation of improvement with short-acting ß2-agonists (SABA) (with or without oral corticosteroids) by a trained health care practitioner during an acute exacerbation (preferred method). However, in children with no wheezing (or other signs of airflow obstruction) on presentation, reversibility may be determined by convincing parental report of a symptomatic response to a three-month therapeutic trial of a medium dose of inhaled corticosteroids with as-needed SABA (alternative method), or as-needed SABA alone (weaker alternative method). The authors provide key messages regarding in whom to consider the diagnosis, terms to be abandoned, when to refer to an asthma specialist and the initial management strategy. Finally, dissemination plans and priority areas for research are identified.

L'asthme fait souvent son apparition avant l'âge de six ans. Cependant, il subsiste des incertitudes relativement à quand et comment un enfant d'âge préscolaire ayant des symptômes de type asthmatique peut être diagnostiqué avec cette condition. Ceci retarde le traitement et contribue à la morbidité à court et à long terme. L'Assemblée clinique sur l'asthme de la Société canadienne de thoracologie s'est associée à la Société canadienne de pédiatrie pour créer un groupe de travail conjoint afin de préparer un document de principes sur le diagnostic et la prise en charge de l'asthme chez les enfants d'âge préscolaire. En l'absence de mesures de la fonction pulmonaire, le diagnostic d'asthme devrait être envisagé chez les enfants de un à cinq ans ayant des symptômes de type asthmatique fréquents (≥8 jours/mois) ou des exacerbations récurrentes (≥2) (épisodes accompagnés de signes compatibles). Le diagnostic nécessite une documentation objective des signes cliniques ou un compte rendu parental convaincant de symptômes d'obstruction des voies respiratoires et de réversibilité de l' obstruction (amélioration suite à un traitement pour l'asthme), ainsi que l'absence de suspicion clinique de tout autre diagnostic. La respiration sifflante, souvent accompagnée de difficultés respiratoires et de toux, est le signe cardinal de l'obstruction des voies respiratoires. La réversibilité à la suite de la prise de médicaments pour l'asthme se définie par l'observation directe par un professionnel de la santé compétent, d'une amélioration après l'administration de ß2-agonistes à courte durée d'action (BACA) (accompagnés ou non de corticostéroïdes par voie orale) pendant une exacerbation aigue (méthode diagnostique privilégiée). Cependant, chez les enfants qui n'ont pas à l'examen une respiration sifflante (ni d'autres signes d'obstruction des voies respiratoires), la réversibilité peut être déterminée par un compte rendu parental convaincant d'une réponse symptomatique à un essai thérapeutique de trois mois de corticostéroïdes inhalés, à dose moyenne, avec un BACA au besoin (méthode diagnostique alternative), ou avec seulement un BACA au besoin (méthode diagnostique alternative moins certaine) est recommandé. Les auteurs présentent des messages clés quant aux enfants chez lesquels on doit envisager le diagnostic, quant aux termes désuets à abandonner, quant aux situations pour lesquelles on doit orienter l'enfant vers un spécialiste de l'asthme et quant à la stratégie de prise en charge initiale. Enfin, ils décrivent la stratégie de diffusion de ces messages et identifient les domaines de recherche prioritaires.

Verifying a questionnaire diagnosis of asthma in children using health claims data.

BACKGROUND: Childhood asthma prevalence is widely measured by parental proxy report of physician-diagnosed asthma in questionnaires. Our objective was to validate this measure in a North American population. METHODS: The 2884 study participants were a subsample of 5619 school children aged 5 to 9 years from 231 schools participating in the Toronto Child Health Evaluation Questionnaire study in 2006. We compared agreement between "questionnaire diagnosis" and a previously validated "health claims data diagnosis". Sensitivity, specificity and kappa were calculated for the questionnaire diagnosis using the health claims diagnosis as the reference standard. RESULTS: Prevalence of asthma was 15.7% by questionnaire and 21.4% by health claims data. Questionnaire diagnosis was insensitive (59.0%) but specific (95.9%) for asthma. When children with asthma-related symptoms were excluded, the sensitivity increased (83.6%), and specificity remained high (93.6%). CONCLUSIONS: Our results show that parental report of asthma by questionnaire has low sensitivity but high specificity as an asthma prevalence measure. In addition, children with "asthma-related symptoms" may represent a large fraction of under-diagnosed asthma and they should be excluded from the inception cohort for risk factor studies.

Juvenile Dermatomyositis and Acute Respiratory Failure in a Teen.

CASE PRESENTATION: A 17-year-old previously healthy Taiwanese girl presented with syncope on a background of 1 month of weakness, polyarthritis, and heliotrope rash. Her presentation and investigations, which included an elevated creatine phosphokinase level and diffuse myositis on lower limb MRI, were consistent with juvenile dermatomyositis (JDM).

A Systematic Review of the Clinical Efficacy and Safety of CFTR Modulators in Cystic Fibrosis.

Several placebo-controlled trials have been recently published evaluating novel therapies targeting the defective CFTR protein. This systematic review examines the clinical efficacy and safety of CFTR modulators in individuals with cystic fibrosis (CF) with specific genetic mutations. Online sources were searched for placebo-controlled, parallel-design clinical trials investigating CFTR modulators from January 1, 2005 to March 31, 2018. The primary outcome of interest was FEV1% predicted (ppFEV1). Fourteen RCTs met our eligibility criteria. The largest improvement in ppFEV1 favouring treatment was observed for ivacaftor (IVA) in G551D individuals (≥6 years old). Both tezacaftor-ivacaftor (TEZ-IVA) and lumacaftor-ivacaftor (LUM-IVA) also improved ppFEV1 in F508del homozygous individuals but there was increased reporting of respiratory adverse events with LUM-IVA compared to placebo. IVA also significantly improved ppFEV1 in a sub-group of individuals ≥18 years old with an R117H mutation. No significant improvements in ppFEV1 were observed for IVA, LUM, or TEZ in F508del homozygous individuals, LUM or LUM-IVA in F508del heterozygous individuals, or ataluren in individuals with a nonsense mutation. Significant improvements in ppFEV1 and other clinical outcomes were observed for IVA in G551D individuals, TEV-IVA and LUM-IVA in F508del homozygous individuals, and IVA in adults with a R117H mutation.

An investigation into biomarkers for the diagnosis of ABPA and aspergillus disease in cystic fibrosis.

BACKGROUND: Allergic bronchopulmonary aspergillosis (ABPA) is a hypersensitivity lung disease due to Aspergillus fumigatus (Af) which occurs in 10% of patients with cystic fibrosis (CF). ABPA is associated with increased morbidity and accelerated lung function decline; however, existing diagnostic criteria are nonspecific and diagnosis remains challenging. As ABPA is driven by Th2 inflammation, the aim of this study was to evaluate exhaled nitric oxide (FE NO ), eosinophilic cationic protein (ECP), peripheral eosinophil count, and bronchodilator response (BDR) in patients with CF. METHODS: A prospective observational cohort study of pediatric CF patients in a tertiary center. Patients had a clinical and serologic ABPA assessment, FENO , serum ECP, peripheral eosinophil count, and assessment of BDR. Patients were stratified into three groups; ABPA, Af sensitized (AFS), and non-ABPA non-Af-sensitized (non-AFS). RESULTS: A total of 62 patients were included in the study: 13% ABPA, 19% AFS, and 68% non-AFS. Mean FENO was higher in the ABPA group at 37.8 ppb compared to AFS 15.1 ppb (P = .05) and non-AFS 13.7 ppb (P = .04). Mean peripheral eosinophil count in ABPA group was also higher at 1000 cells/uL, compared to AFS 221 cells/uL (P = .03) and non-AFS 220 cells/uL (P = .03). Mean BDR in ABPA group was 13% compared to 5.5% in non-AFS (P = .01). Serum ECP was higher in patients with ABPA positive compared to the other groups, although this was not statistically significant. CONCLUSION: In children with cystic fibrosis, FENO and peripheral eosinophil counts are elevated in ABPA compared to those that are just sensitized to Aspergillus and may serve as useful diagnostic tests.

Intrapleural Dornase and Tissue Plasminogen Activator in pediatric empyema (DTPA): a study protocol for a randomized controlled trial.

BACKGROUND: A randomized controlled trial of adults with empyema recently demonstrated decreased length of stay in hospital in patients treated with intrapleurally administered dornase alfa and fibrinolytics compared to fibrinolytics alone. Whether this treatment strategy is safe and effective in children remains unknown. METHODS/DESIGN: This study protocol is for a superiority, placebo-controlled, parallel-design, multicenter randomized controlled trial. The participants are previously well children admitted to a children's hospital with a diagnosis of empyema requiring chest tube insertion and fibrinolytics administered intrapleurally. Children will be randomized after the treating physician has decided that pleural drainage is required but prior to chest tube insertion. After chest tube insertion, participants in the treatment group will receive intrapleurally administered tissue plasminogen activator (tPA) 4 mg followed by dornase alfa 5 mg. Participants in the placebo group will receive tPA 4 mg followed by normal saline. Study treatments will be administered once daily for 3 days. All participants, parents or caregivers, clinicians, and research personnel will remain blinded. The primary outcome is length of stay from chest tube insertion to discharge from hospital. Secondary outcomes include time to meeting discharge criteria, chest tube duration, fever duration, need for additional procedures, adverse events, hospital readmission, cost of hospitalization, and mortality. DISCUSSION: This multicenter randomized controlled trial will assess the safety, effectiveness, and cost-effectiveness of combined treatment with dornase alfa and fibrinolytics compared to fibrinolytics alone for the treatment of empyema in children. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01717742 . Registered on 8 October 2012.

Respiratory Presentation of Pediatric Patients in the 2014 Enterovirus D68 Outbreak.

Background. In the fall of 2014, a North American outbreak of enterovirus D68 resulted in a significant number of pediatric hospital admissions for respiratory illness throughout North America. This study characterized the clinical presentation and risk factors for a severe clinical course in children admitted to British Columbia Children's Hospital during the 2014 outbreak. Methods. Retrospective chart review of patients with confirmed EV-D68 infection admitted to BCCH with respiratory symptoms in the fall of 2014. Past medical history, clinical presentation, management, and course in hospital was collected and analyzed using descriptive statistics. Comparison was made between those that did and did not require ICU admission to identify risk factors. Results. Thirty-four patients were included (median age 7.5 years). Fifty-three percent of children had a prior history of wheeze, 32% had other preexisting medical comorbidities, and 15% were previously healthy. Ten children (29%) were admitted to the pediatric intensive care unit. The presence of complex medical conditions (excluding wheezing) (P = 0.03) and copathogens was associated with PICU admission (P = 0.02). Conclusions. EV-D68 infection resulted in severe, prolonged presentations of asthma-like illness in the hospitalized pediatric population. Patients with a prior history of wheeze and preexisting medical comorbidities appear to be most severely affected, but the virus can also cause wheezing in previously well children.