Congenital laryngomalacia is related to exercise-induced laryngeal obstruction in adolescence

Characteristics and outcomes of interventions for pediatric laryngomalacia: A systematic review with meta-analysis

OBJECTIVES

To analyze characteristics of children treated for laryngomalacia to determine predictive factors and provide an updated meta-analysis on outcomes.

METHODS

A systematic review was conducted according to PRISMA guidelines from inception to May 2, 2023, using CINAHL, PubMed, and Scopus databases. Study screening, data extraction, quality rating, and risk of bias assessment were performed by 2 independent reviewers. Data were meta-analyzed using fixed-/random-effects model to derive continuous measures (mean), proportions (%), and mean difference (Δ) with 95% confidence interval (CI).

RESULTS

100 articles were identified with information on outcomes of pediatric patients with laryngomalacia (N = 18,317). The mean age was 10.6 months (range: 0 to 252, 95%CI: 9.6 to 11.6, p = 0.00) with a 1.4:1 male to female ratio. Many patients presented with stridor (87.9%, 95% CI: 69.8 to 98.4), and the most common comorbidity at time of diagnosis was gastroesophageal reflux disease (48.8%, 95%CI: 40.9 to 56.8). Based on the patient population included in our analysis, 86.1% received supraglottoplasty (95% CI: 78.7 to 92.1). A total of 73.6% (95% CI: 65.5 to 81.0) had reported complete resolution of symptoms. For patients with a concurrent diagnosis of sleep disordered breathing receiving supraglottoplasty, the apnea-hypopnea index improved with a mean difference of -10.0 (95%CI: 15.6 to -4.5) events per hour post-treatment.

CONCLUSIONS

Laryngomalacia continues to be a common problem in the pediatric population. Supraglottoplasty remains an effective treatment option leading to symptomatic improvement in many cases. For those with concurrent sleep disordered breathing, supraglottoplasty lowers the apnea-hypopnea index.

Resting Respiratory Resistance in Female Teenage Athletes With and Without Exercise-Induced Laryngeal Obstruction

OBJECTIVE

Exercise-induced laryngeal obstruction (EILO) occurs with paradoxical vocal fold motion or supraglottic collapse during moderate to vigorous exercise. Previously, Gallena et al (2015) reported lower-than-normal inspiratory (Ri) and expiratory (Re) resistances during resting tidal breathing (RTB) in female teenage athletes with EILO. This study aimed to replicate that unexpected result.

METHOD

The Airflow Perturbation Device measured Ri and Re during three 1-minute trials of RTB in 16 teenage female athletes with EILO and 16 sex-, age-, and height-matched controls. Multiple linear regression examined group, age, height, and weight as predictors of Ri and Re.

RESULTS

Ri and Re tended to be lower in the EILO group than the control group [Ri: F(1,30) = 3.58, P = 0.068, d = 0.686; Re: F(1,30) = 3.28, P = 0.080, d = 0.640], but there was no statistically significant difference in the overall effect [F(2,29) = 1.75, P = 0.192]. After one outlier for Re from the EILO group and her matched control were removed, the overall difference was statistically significant, F(2,27) = 3.38, P = 0.049, with Re primarily contributing to the difference [Ri: F(1,28) = 3.66, P = 0.066, d = 0.719; Re: F(1,28) = 5.69, P = 0.024, d = 0.899].

CONCLUSION

These results did not replicate the robust differences found previously between Ri and Re during RTB in teenage girls with and without EILO, but the results trended in the same direction and met criterion for statistical significance once an outlier was removed from analysis. Overall, the observation that resting respiratory resistances were lower in most teenage girls with EILO suggests that reduced tone of the laryngeal and/or lower airways may predispose young athletes to EILO.

A case of vocal cord dysfunction in the emergency department

We describe the case of a 78-year-old woman admitted to our emergency department for an acute onset of severe dyspnoea with inspiratory wheezing-like sounds. She denied fever, cough, voice change and pain. She referred a similar but less severe episode occurred spontaneously one year before, with complete resolution in few minutes without sequelae. On examination upper airway obstruction was firstly excluded. She was initially treated as having asthma, without response. Parenteral high dose corticosteroids and antihistamines provided no benefit. Point-of-care-ultrasound resulted normal. Flexible laryngoscopy during the episode showed paradoxical vocal cord movement with adduction during both inspiration and expiration. This demonstrated that her dyspnoea was from Vocal Cord Dysfunction (VCD). VCD completely solved after administration of intravenous benzodiazepines.

International Olympic Committee (IOC) consensus statement on acute respiratory illness in athletes part 2: non-infective acute respiratory illness

Acute respiratory illness (ARill) is common and threatens the health of athletes. ARill in athletes forms a significant component of the work of Sport and Exercise Medicine (SEM) clinicians. The aim of this consensus is to provide the SEM clinician with an overview and practical clinical approach to non-infective ARill in athletes. The International Olympic Committee (IOC) Medical and Scientific Committee appointed an international consensus group to review ARill in athletes. Key areas of ARill in athletes were originally identified and six subgroups of the IOC Consensus group established to review the following aspects: (1) epidemiology/risk factors for ARill, (2) infective ARill, (3) non-infective ARill, (4) acute asthma/exercise-induced bronchoconstriction and related conditions, (5) effects of ARill on exercise/sports performance, medical complications/return-to-sport (RTS) and (6) acute nasal/laryngeal obstruction presenting as ARill. Following several reviews conducted by subgroups, the sections of the consensus documents were allocated to 'core' members for drafting and internal review. An advanced draft of the consensus document was discussed during a meeting of the main consensus core group, and final edits were completed prior to submission of the manuscript. This document (part 2) of this consensus focuses on respiratory conditions causing non-infective ARill in athletes. These include non-inflammatory obstructive nasal, laryngeal, tracheal or bronchial conditions or non-infective inflammatory conditions of the respiratory epithelium that affect the upper and/or lower airways, frequently as a continuum. The following aspects of more common as well as lesser-known non-infective ARill in athletes are reviewed: epidemiology, risk factors, pathology/pathophysiology, clinical presentation and diagnosis, management, prevention, medical considerations and risks of illness during exercise, effects of illness on exercise/sports performance and RTS guidelines.

Exercise-induced laryngeal obstruction (EILO) in athletes: a narrative review by a subgroup of the IOC Consensus on 'acute respiratory illness in the athlete'

Exercise-induced laryngeal obstruction (EILO) is caused by paradoxical inspiratory adduction of laryngeal structures during exercise. EILO is an important cause of upper airway dysfunction in young individuals and athletes, can impair exercise performance and mimic lower airway dysfunction, such as asthma and/or exercise-induced bronchoconstriction. Over the past two decades, there has been considerable progress in the recognition and assessment of EILO in sports medicine. EILO is a highly prevalent cause of unexplained dyspnoea and wheeze in athletes. The preferred diagnostic approach is continuous visualisation of the larynx (via laryngoscopy) during high-intensity exercise. Recent data suggest that EILO consists of different subtypes, possibly caused via different mechanisms. Several therapeutic interventions for EILO are now in widespread use, but to date, no randomised clinical trials have been performed to assess their efficacy or inform robust management strategies. The aim of this review is to provide a state-of-the-art overview of EILO and guidance for clinicians evaluating and treating suspected cases of EILO in athletes. Specifically, this review examines the pathophysiology of EILO, outlines a diagnostic approach and presents current therapeutic algorithms. The key unmet needs and future priorities for research in this area are also covered.

Die induzierbare laryngeale Obstruktion (ILO) – Ursachen, klinische Präsentation, Diagnostik und Therapie: Positionspaper der Arbeitsgruppe „Dysfunktionelle Respiratorische Symptome“ der Gesellschaft für Pädiatrische Pneumologie (GPP)

Wiederholt episodenhaft auftretende Atemnot ist im Kindes- und Jugendalter ein häufiges Symptom. Neben anstrengungsinduzierter Bronchialobstruktion im Rahmen eines Asthma bronchiale ist eine funktionelle Genese eine sehr häufige Differenzialdiagnose. Dennoch wird diese Diagnose häufig nicht oder mit langer Latenz gestellt. Unter dem Oberbegriff „ILO“ („inducible laryngeal obstruction“) werden sowohl funktionelle supraglottische Obstruktionen durch Kollaps der Knorpelstrukturen als auch Dysfunktionen auf Glottisebene wie „vocal cord dysfunction“ (VCD) subsumiert. Körperliche Anstrengung ist ein häufiger Auslöser; es werden jedoch auch Beschwerdebilder ohne Anstrengungsbezug beobachtet. Es wird der Erkenntnisstand zur Pathophysiologie referiert und die klinische Präsentation beschrieben. Ein wesentlicher Fokus des Artikels liegt im Folgenden auf der Darstellung eines sinnvollen und Ressourcen-orientierten diagnostischen Vorgehens. Der CLE-Test („continuous laryngoscopy exercise test“) als Provokationsmethode unter Wach-Videolaryngoskopie ist der Goldstandard, jedoch wird diese Diagnostik im deutschsprachigen Raum nicht flächendeckend vorgehalten. Dieses Positionspapier stellt daher die diagnostische Wertigkeit verschiedener anderer Diagnostik-Algorithmen und anamnestischer Informationen heraus. Ein weiterer Schwerpunkt des Papiers besteht in der detaillierten Vorstellung geeigneter atemphysiotherapeutischer Interventionen.

Development and validation of the Exercise-Induced Laryngeal Obstruction Dyspnea Index (EILODI)

BACKGROUND

Exercise-induced laryngeal obstruction (EILO) causes exertional dyspnea and is important for its effect on quality of life, diagnostic confusion with exercise-induced asthma, and health care resource utilization. There is no validated patient-reported outcome measure specific to EILO.

OBJECTIVE

We sought to develop, validate, and define a minimal clinically important difference for a patient-reported outcome measure to be used with adolescents and young adults with EILO.

METHODS

A multidisciplinary group created a preliminary measure, modified by a 10-member participant focus group, with 20 items scored along a 5-point Likert scale. A subsequent cohort of participants recruited from a clinic, aged 12 to 21 years, with confirmed EILO by continuous laryngoscopy during exercise testing (1) completed the measure at 3 points in time over 28 days and (2) provided anchoring data in the form of a daily exercise log and categorical self-assessments of clinical improvement. Thirty additional participants without exertional dyspnea served as controls.

RESULTS

Two hundred nineteen subjects with mild to severe EILO participated in the exploratory factor analysis, which identified 7 factors within the preliminary outcome measure. After a process of item reduction, a 12-item metric with a total score ranging from 0 to 48 was developed. Mean scores of patients with EILO and healthy controls at baseline were 28.8 ± 7.4 and 4.5 ± 7.4, respectively. A minimal clinically important difference of 6 was determined by comparison of index change with changes in categorical self-assessments of improvement.

CONCLUSIONS

This is the first patient-reported outcome measure specifically designed for adolescents and young adults with EILO.

Functional Respiratory Disorders in Children

Functional respiratory disorders (FRDs) are those characterized by respiratory symptoms without anatomic or organic etiology. Clinicians caring for children encounter these disorders and should be familiar with diagnosis and treatment. FRDs encompass the habit cough syndrome and its variants, vocal cord dysfunction, hyperventilation disorders, functional dyspnea, and sighing syndrome. Failure to identify these disorders results in unnecessary testing and medication. This article reviews the clinical presentation, manifestation, and treatment of respiratory FRDs in children. How health care providers can successfully identify and treat these reversible conditions in the clinical setting is discussed.

Exercise-Associated Dyspnea and Stridor: Thinking Beyond Asthma

Breathlessness during sport can be caused by various cardiorespiratory conditions, but when associated with stridor, usually arises from an upper airway etiology. The term exercise-induced laryngeal obstruction (EILO) is now used to describe the phenomenon of transient glottic closure occurring in association with physical activity. Exercise-related laryngeal closure is most commonly encountered in athletic individuals and likely affects between 5% and 7% of all young adults and adolescents. The diagnosis of EILO is not always straightforward because features can overlap with exercise-induced asthma/exercise-induced bronchoconstriction. EILO can therefore remain misdiagnosed for years, and most patients receive inappropriate asthma therapy. In contrast with asthma, EILO symptoms are usually most prominent at maximal exercise intensity and resolve quickly on exercise cessation. It is important to recognize that EILO and asthma can coexist in a proportion of athletes. The criterion standard test for diagnosing EILO is continuous laryngoscopy during exercise testing, although eucapnic voluntary hyperpnea testing has also been used. Various surgical or pharmacological interventions can be used to treat EILO, but first-line treatment is breathing technique work. Further research is needed to establish the optimal treatment algorithm, and more work is needed to increase awareness of this important clinical entity.

Exercise-induced laryngeal obstruction (EILO) in children and young adults: From referral to diagnosis

OBJECTIVE

To identify different presentations, referral patterns, comorbidities, and laryngoscopy findings in children and young adults with exercise-induced laryngeal obstruction (EILO).

METHODS

We performed a retrospective chart review of 112 patients, age <26 years, with EILO between 2013 and 2016.

RESULTS

Of the 112 patients who met criteria, 91 were female and 21 were male. Patients were most frequently referred by pulmonologists (60.7%). The majority of patients (93%) participated in organized sports, most of them at a competitive level. The mean age at symptom onset was 13.8 ± 3.3 years, and the mean age of diagnosis was 15.4 ± 3.0 years. Sixty-seven (59.8%) patients presented with a prior diagnosis of asthma, the majority of whom had failed asthma treatment. The most common symptoms reported were dyspnea (93.8%), wheezing/stridor (78.6%), and throat tightness (48.2%). Ninety-one (81.3%) patients had spirometry performed, with 46 (51.1%) showing inspiratory loop flattening. On flexible laryngoscopy, 87 (78.4%) of 111 patients had paradoxical vocal fold motion. Supraglottic involvement was observed to obstruct the airway in 26 (23.9%) patients, with patterns of obstruction similar to those observed in children with laryngomalacia.

CONCLUSION

Most patients participated in competitive sports, were female, and presented with exertional dyspnea. Most patients were diagnosed with exercise-induced asthma but treated unsuccessfully. Almost one-quarter of our patients showed supraglottic collapse obstructing the airway. Exercise-induced laryngeal obstruction is a more descriptive term than paradoxical vocal fold motion or vocal cord dysfunction, which only describe vocal fold involvement. The time to diagnosis of EILO was shorter than previously reported, suggesting that awareness of this condition is increasing.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:E400-E406, 2020.

Severe Exercise-Induced Laryngeal Obstruction Treated With Supraglottoplasty

Introduction: Exercise induced laryngeal obstruction (EILO) is relatively common in adolescents, with symptoms often confused with exercise induced asthma. EILO often starts with medial or inward rotation of supraglottic structures of the larynx, whereas glottic adduction appears as a secondary phenomenon in a majority. Therefore, surgical treatment (supraglottoplasty) is used in thoroughly selected and highly motivated patients with pronounced symptoms and severe supraglottic collapse.

Aim: To investigate efficacy and safety of laser supraglottoplasty as treatment for severe supraglottic EILO by retrospective chart reviews.

Methods: The EILO register at Haukeland University Hospital, Bergen, Norway was used to identify patients who had undergone laser supraglottoplasty for severe supraglottic EILO, verified by continuous laryngoscopy exercise (CLE) test, during 2013–2015. Laser incision in both aryepiglottic folds anterior to the cuneiform tubercles and removal of the mucosa around the top was performed in general anesthesia. Outcomes were questionnaire based self-reported symptoms, and laryngeal obstruction scored according to a defined scheme during a CLE-test performed before and after surgery.

Results: Forty-five of 65 eligible patients, mean age 15.9 years, were included. Post-operatively, 38/45 (84%) patients reported less symptoms, whereas CLE-test scores had improved in all, of whom 16/45 (36%) had no signs of obstruction. Most improvements were at the supraglottic level, but 21/45 (47%) also improved at the glottic level. Two of 65 patients had complications; self-limiting vocal fold paresis and scarring/shortening of plica ary-epiglottica.

Conclusion: Supraglottoplasty improves symptoms and decreases laryngeal obstruction in patients with severe supraglottic EILO, and appears safe in highly selected cases.

Dynamic tonsillar prolapse masquerading as paradoxical vocal fold movement dysfunction

INTRODUCTION

Paradoxical vocal fold movement dysfunction (PVFMD) is a disorder in which the vocal folds involuntarily adduct during inspiration resulting in stridor, cough, dysphonia and dyspnea. Diagnosis of PVFMD is difficult given the episodic nature of the disorder and the often-normal laryngeal exam in between episodes. Moreover, additional sources of obstruction have been identified as sources of Periodic Occurrence of Laryngeal Obstruction (POLO). Treatments can vary with site of obstruction.

OBJECTIVE

To evaluate pediatric patients presenting to a Vocal Fold Dysfunction Center for evaluation of exertional, inspiratory, harsh breath sounds and dyspnea suggestive of PVFMD whom were found to have a dynamic obstruction of the upper airway due to adenotonsillar hypertrophy and prolapse.

METHODS

Retrospective chart review of patients diagnosed with exertional dynamic tonsillar prolapse whom have undergone adenotonsillectomy. Clinical characteristics, spirometry, exam findings and response to adenotonsillectomy were recorded.

RESULTS

Seven patients with exercise induced dyspnea and respiratory distress with whom underwent exercise spirometry then subsequent adenotonsillectomy were identified. Symptomatic co-morbidities were common and included: rhinitis (43%), reflux (29%), sleep disordered breathing (29%), asthma (14%), obesity (14%), prematurity (14%) and anxiety/post-traumatic stress disorder (PTSD) (14%). Preoperative use of bronchodilators or reflux medications was common. All patients were noted to have >50% oropharyngeal obstruction secondary to tonsillar hypertrophy and dynamic lateral pharyngeal collapse or tonsillar prolapse with inspiration. No exercise induced paradoxical vocal fold dysfunction was identified. All baseline and most exertion FVC, FEV1, FEV1/FVC and FEF 25-75% were normal. Four patients had flow volume loops suggestive of obstruction. All patients had symptomatic improvement after adenotonsillectomy.

CONCLUSIONS

Dynamic tonsillar prolapse can result in subjective exertional dyspnea and objective upper airway resistance mimicking PVFMD and treatment with adenotonsillectomy can greatly reduce symptoms.

Exercise-Induced Dyspnea in Children and Adolescents: Differential Diagnosis

Exercise-induced dyspnea in children and adolescents can occur for many reasons. Although asthma is the common cause, failure to prevent exercise-induced asthma by pretreatment with a bronchodilator, such as albuterol, indicates that other etiologies should be considered. Other causes of exercise-induced dyspnea include exercise-induced vocal cord dysfunction, exercise-induced laryngomalacia, exercise-induced hyperventilation, chest wall restrictive abnormalities, cardiac causes, and normal physiologic limitation. When exercise-induced dyspnea is not from asthma, cardiopulmonary exercise testing with reproduction of the patient's dyspnea is the means to identify the other causes. Cardiopulmonary exercise testing monitors oxygen use, carbon-dioxide production, end-tidal pCO₂ (partial pressure of carbon dioxide), and electrocardiogram. Additional components to testing are measurement of blood pH and pCO₂ when symptoms are reproduced, and selective flexible laryngoscopy when upper airway obstruction is observed to specifically identify vocal cord dysfunction or laryngomalacia. This approach is a highly effective means to identify exercise-induced dyspnea that is not caused by asthma. [Pediatr Ann. 2019;48(3):e121-e127.].

Exercise-induced laryngeal obstruction in athletes treated with inspiratory muscle training

Background

Exercise-induced laryngeal obstruction (EILO) is common in athletes and presents with dyspnoea, chest tightness, inspiratory stridor and sometimes panic reactions. The evidence for conservative treatment is weak, but case reports suggest effects from inspiratory muscle training (IMT). We aimed to explore effects from IMT used in athletes with EILO.

Method

Twenty-eight athletes, mean age 16.4 years, diagnosed with EILO at our clinic, participated in a 6-week treatment programme, using a resistive flow-dependent IMT device (Respifit S). Four athletes competed at international level, 13 at national and 11 at regional levels. Video-recorded continuous transnasal flexible laryngoscopy was performed from rest to peak exercise (continuous laryngoscopy exercise (CLE) test) and scored before and 2–4 weeks after the training period. Ergospirometric variables were obtained from this CLE set-up. Lung function was measured according to guidelines. Symptom scores and demographic variables were obtained from a questionnaire.

Results

After the treatment period, symptoms had decreased in 22/28 (79%) participants. Mean overall CLE score had improved after treatment (p<0.001), with the scores becoming normal in five athletes but worse in two. Most of the improvement was explained by changes at the glottic laryngeal level (p=0.009). Ergospirometric variables revealed significantly higher peak minute ventilation explained by higher tidal volumes and were otherwise unchanged.

Conclusion

This explorative study underlines the heterogeneous treatment response of EILO and suggests that IMT may become an efficient conservative treatment tool in subgroups, possibly contributing to better control of the vocal folds. The signals from this study should be tested in future controlled interventional studies.

Exercise-Induced Laryngeal Obstruction: When Pediatric Exertional Dyspnea Does not Respond to Bronchodilators

Exertional dyspnea is a common complaint in general pediatric practice. While a high proportion of the general pediatric population has asthma, other diagnoses, including exercise-induced laryngeal obstruction should be considered, especially when asthma therapy is not sufficient to control symptoms. This review describes some of the key clinical features of exercised-induced laryngeal obstruction as well as preferred diagnostic and therapeutic approaches. Importantly, current diagnostic technology has considerably improved in the last decade at specialty centers. At the same time, infrastructure for clinical trials is emerging and there is not strong evidence to support specific therapies at the current time.

Management of asthma in children

This manuscript takes a challenging look at the management of asthma in childhood, in particular in the light of the recent Lancet commission. One of the central pillars of the Commission is the need to deliver personalized medicine for airway disease by deconstructing the airway into components of fixed and variable airflow obstruction, inflammation and infection. Before any treatment for asthma, a diagnostic workup is essential to exclude other conditions. A diagnosis of asthma needs to be based on objective evidence of bronchodilator sensitive variable airflow obstruction, eosinophilic airway inflammation and atopy. Most children with atopic asthma respond to low dose inhaled corticosteroids, sometimes requiring a long acting β-agonist. If the response is unsatisfactory, then, rather than escalate treatment, an approach for which there is little evidence, a full review of the child should be undertaken, including extrapulmonary comorbidities, adherence and adverse environmental influences. If these cannot or will not be addressed by the family, then further treatment including biologicals may be indicated. Asthma attacks are an important warning sign and should always be taken seriously, including a focused reassessment of all aspects of the management of the child. Finally, preschool children with wheeze can also be evaluated for eosinophilic airway inflammation using peripheral blood eosinophil count as a surrogate. It is essential that we start to deliver personalized medicine to children with airway disease.

Laryngomalacia presenting as severe uncontrolled asthma

Congenital laryngomalacia is the most common cause of stridor in infants and usually resolves without therapy by 12–18 months of age. However, a recent study found that laryngomalacia may leave structural and functional traces with increased risk of later respiratory symptoms, suggesting that late‐onset laryngomalacia may represent long‐term consequences of milder or even undiagnosed forms. Unusual cases demonstrated that inspiratory stridor developed subsequent to upper respiratory tract infections. The lack of airway hyperresponsiveness in adulthood also raised questions regarding the diagnosis of childhood asthma. Laryngomalacia should be distinguished from severe asthma.

Exercise-Induced Laryngeal Obstruction-An Overview

Exertional dyspnea is common in health and disease. Despite having known for centuries that breathlessness can arise from the larynx, exercise-induced laryngeal obstruction is a more prevalent condition than previously assumed. This article provides a brief overview of the history, epidemiology, and pathophysiology of exercise-induced laryngeal obstruction.

Severe asthma in children

Most children with asthma have their disease easily controlled if low-dose inhaled corticosteroids (ICSs) are regularly and correctly administered. If a child presents with asthma which is apparently resistant to therapy with high-dose ICS and other controllers, then they have problematic severe asthma. However, in light of the UK National Review of Asthma Deaths, definitions of severe asthma based solely on the levels of prescribed treatment are too narrow. A detailed assessment of all such children should be performed. First, the diagnosis of asthma should be confirmed, then co-morbidities assessed. Next, a nurse-led assessment further characterizes the problem, conventionally categorizing the child as either having difficult asthma or severe therapy-resistant asthma. Here, we reassess in particular the interactions between, and management of, these two categories, highlighting that this dichotomous classification may need reconsideration. We use bronchoscopy and an intramuscular steroid injection to determine if the child has steroid-resistant asthma, using a novel, multidomain approach because the adult definition does not apply to around half the children we see. Finally, we highlight some mechanistic data which have emerged from this protocol such as the absence of T-helper 2 (TH2) cytokines even in eosinophilic severe asthma and the potential role of the innate epithelial cytokine IL-33, novel data on lineage negative innate lymphoid cells, which we can measure in induced sputum, and demonstrating that intraepithelial neutrophils are associated with better, not worse asthma outcomes. Severe paediatric asthma is very different from severe asthma in adults, and approaches must not be uncritically extrapolated from adult disease to children.

Vocal cord dysfunction: a functional cause of respiratory distress

VCD has several clinical and physiological phenotypes, which should be individually identifiedhttp://ow.ly/orfb309fMxh.

Exercise inducible laryngeal obstruction: diagnostics and management

Obstruction of the central airways is an important cause of exercise-induced inspiratory symptoms (EIIS) in young and otherwise healthy individuals. This is a large, heterogeneous and vastly understudied group of patients. The symptoms are too often confused with those of asthma. Laryngoscopy performed as symptoms evolve during increasing exercise is pivotal, since the larynx plays an important role in symptomatology for the majority. Abnormalities vary between patients, and laryngoscopic findings are important for correct treatment and handling. The simplistic view that all EIIS is due to vocal cord dysfunction [VCD] still hampers science and patient management. Causal mechanisms are poorly understood. Most treatment options are based on weak evidence, but most patients seem to benefit from individualised information and guidance. The place of surgery has not been settled, but supraglottoplasty may cure well-defined severe cases. A systematic clinical approach, more and better research and randomised controlled treatment trials are of utmost importance in this field of respiratory medicine.