Measuring persistent cough in children in epidemiological studies: development of a questionnaire and assessment of prevalence in two countries

Coin Aspiration Presenting as Chronic Cough and Tracheoesophageal Fistula

Chronic cough can be a diagnostic challenge in the pediatric population. Foreign body aspiration without typical signs and symptoms can often be overlooked as a cause of chronic cough in children. Coin aspirations in the trachea typically have a sagittal orientation on an anteroposterior (AP) chest radiograph. We report a rare case of a previously healthy five-year-old girl presenting with a chronic cough for five months caused by a coin with a coronal orientation on an AP chest radiograph. The coin, initially presumed to be lodged in the esophagus, was actually lodged in the cervical trachea, leading to the development of a tracheoesophageal fistula (TEF). Her AP chest radiograph showed a coronal, circular radio-opaque shadow and the lateral view a tangential radio-opaque shadow, prompting an initial evaluation by esophagogastroduodenoscopy, which was normal. She then underwent rigid bronchoscopy, revealing a coin lodged in the trachea along with a TEF. Surgical removal was achieved through an external approach with a vertical tracheotomy and insertion of a tracheostomy tube. Five days later, a repeat rigid bronchoscopy showed a well-healed TEF, and she was successfully decannulated. She was ultimately discharged home on room air and oral feeds. TEF as a complication of a foreign body lodged in the trachea or esophagus is rare but life-threatening. Foreign body aspiration should always be considered in the differential diagnosis when evaluating younger children with chronic cough.

Methacholine and FeNO Measurement in Patients with Habit Cough

BACKGROUND

Chronic cough is one of the most common symptoms in childhood. Making a definite diagnosis is a challenge for all pediatricians especially in patients when cough is without an organic cause like in habit cough.

PATIENTS AND METHODS

In this retrospective analysis, all electronic outpatient charts of the Division of Allergology and Pneumology, between January 1, 2010 and December 31, 2019 were reviewed in order to study all children with potential habit cough. All children underwent the following diagnostic algorithms, skin prick test (SPT), measurement of fractional exhaled nitric oxide (FeNO), spirometry and methacholine challenge test (MCT). The value of a normal MCT and FeNO measurement for diagnosing habit cough was investigated.

RESULTS

The chart review revealed 482 patients with chronic cough>4 weeks. Of these, 99 (20.5%) with suspected habit cough were collected. 13 patients had to be excluded for other diagnosis and a complete data set was available in 55 patients. 33 (60.0%) of 55 patients were SPT negative and 22 (40.0%) had sensitization to common allergens. Five patients had elevated FeNO≥20 ppb and three showed severe bronchial hyperresponsiveness<0.1 mg methacholine, challenging the diagnosis of habit cough.

CONCLUSION

A normal FeNO and MCT can help confirm the clinical diagnosis of habit cough. However, in patients with positive MCT and/or elevated FeNO habit cough can be present. Especially in patients with elevated FeNO and severe BHR cough variant asthma and eosinophilic bronchitis have to be ruled out.

Therapeutic principles and unmet needs in the treatment of cough in pediatric patients: review and expert survey

BACKGROUND

There are evidence gaps in the management of pediatric cough, particularly for acute pediatric cough. This study had two aims: to identify therapeutic principles and unmet needs in the treatment of cough in pediatric patients (internationally), and to consider the evidence required to address these unmet needs.

METHODS

A MEDLINE/PubMed database search was performed to identify articles describing therapeutic principles in the treatment of pediatric cough. An online survey of international pediatric cough experts was conducted, with questions on the definitions, diagnosis, treatment, and unmet needs in pediatric cough management.

RESULTS

Cough guidelines have differing definitions of pediatric patients (≤12-18 years), acute pediatric cough (< 2-3 weeks), and chronic pediatric cough (> 4-8 weeks). Similarly, among 18 experts surveyed, definitions varied for pediatric patients (≤10-21 years), acute pediatric cough (< 3-5 days to < 6 weeks), and chronic pediatric cough (> 2-8 weeks). Guidelines generally do not recommend over-the-counter or prescription cough medicines in acute pediatric cough, due to lack of evidence. In the expert survey, participants had differing opinions on which medicines were most suitable for treating acute pediatric cough, and noted that effective treatments are lacking for cough-related pain and sleep disruption. Overall, guidelines and experts agreed that chronic pediatric cough requires diagnostic investigations to identify the underlying cough-causing disease and thereby to guide treatment. There are unmet needs for new effective and safe treatments for acute pediatric cough, and for randomized controlled trials of existing treatments. Safety is a particular concern in this vulnerable patient population. There is also a need for better understanding of the causes, phenotypes, and prevalence of pediatric cough, and how this relates to its diagnosis and treatment.

CONCLUSIONS

Whereas pediatric cough guidelines largely align with regard to the diagnosis and treatment of chronic cough, there is limited evidence-based guidance for the management of acute cough. There is a need for harmonization of pediatric cough management, and the development of standard guidelines suitable for all regions and patient circumstances.

Cough hypersensitivity and chronic cough

Chronic cough is globally prevalent across all age groups. This disorder is challenging to treat because many pulmonary and extrapulmonary conditions can present with chronic cough, and cough can also be present without any identifiable underlying cause or be refractory to therapies that improve associated conditions. Most patients with chronic cough have cough hypersensitivity, which is characterized by increased neural responsivity to a range of stimuli that affect the airways and lungs, and other tissues innervated by common nerve supplies. Cough hypersensitivity presents as excessive coughing often in response to relatively innocuous stimuli, causing significant psychophysical morbidity and affecting patients' quality of life. Understanding of the mechanisms that contribute to cough hypersensitivity and excessive coughing in different patient populations and across the lifespan is advancing and has contributed to the development of new therapies for chronic cough in adults. Owing to differences in the pathology, the organs involved and individual patient factors, treatment of chronic cough is progressing towards a personalized approach, and, in the future, novel ways to endotype patients with cough may prove valuable in management.

Otolaryngologic Management of Chronic Cough in School-aged Children: A Review

Importance

The causes of pediatric chronic cough are numerous and span across several medical subspecialties. In addition to the vast array of underlying causes, there are also several different ways to approach and evaluate chronic cough. Given the frequency with which children present to otolaryngology clinics with this problem, a review of common otolaryngologic causes and an algorithm for evaluation and treatment can be beneficial.

Observations

The primary 3 causes of pediatric chronic cough presenting to an otolaryngologist include infectious causes, reflux, and airway hyperreactivity. In these cases and other instances of specific cough, treatment should be directed at the underlying cause-which may include supportive care, antibiotics, antireflux medication, bronchodilators, inhaled steroids, or other intervention. Patients with nonspecific cough should be treated according to pediatric-specific cough algorithms.

Conclusions and Relevance

Appropriate workup and treatment of chronic cough can lead to higher cure rates, shorter cough duration, and improved quality of life for both patients and caregivers. A systematic approach using cough algorithms can help otolaryngologists effectively manage this common yet complex problem.

An approach to the child with a wet cough

When children have a wet cough, it suggests the presence of secretions in their airways. This often has an infectious aetiology which is usually a self-limiting viral infection requiring no investigation or treatment. In those with acute wet cough it is, however, important to identify features suggestive of community acquired pneumonia or an inhaled foreign body as these causes require specific management. When there is chronic wet cough, the most common diagnoses are protracted bacterial bronchitis (PBB) and bronchiectasis. The relationship between these two conditions is complex as the development of bronchiectasis manifests as a clinical continuum in which the early features of which are indistinguishable from PBB. It is therefore important to identify PBB and chronic cough endotypes which are associated with an increased risk of bronchiectasis. This article offers a pragmatic approach to the investigation and treatment of children with wet cough. It is hoped this will limit unnecessary investigations whist aiding the prompt diagnosis of conditions needing treatment to reduce symptom burden and prevent further lung damage.

'Dry' and 'wet' cough: how reliable is parental reporting?

Introduction

Chronic cough in childhood is common and causes much parental anxiety. Eliciting a diagnosis can be difficult as it is a non-specific symptom indicating airways inflammation and this may be due to a variety of aetiologies. A key part of assessment is obtaining an accurate cough history. It has previously been shown that parental reporting of 'wheeze' is frequently inaccurate. This study aimed to determine whether parental reporting of the quality of a child's cough is likely to be accurate.

Methods

Parents of 48 'new' patients presenting to a respiratory clinic with chronic cough were asked to describe the nature of their child's cough. They were then shown video clips of different types of cough using age-appropriate examples, and their initial report was compared with the types of cough chosen from the video.

Results

In a quarter of cases, the parents chose a video clip of a 'dry' or 'wet' cough having given the opposite description. In a further 20% parents chose examples of both 'dry' and 'wet' coughs despite having used only one descriptor.

Discussion

While the characteristics of a child's cough carry important information that may be helpful in reaching a diagnosis, clinicians should interpret parental reporting of the nature of a child's cough with some caution in that one person's 'dry' cough may very well be another person's 'wet' cough.

Fifteen-minute consultation: A structured approach to the management of chronic cough in a child

Coughing is a primary pulmonary defence mechanism that enhances clearance of secretions and particles from the airways and protects against aspiration of foreign materials. Coughing may affect 30% of children at any given time (1). Many are healthy children but some may have serious underlying disease. Childhood cough accounts for a large number of consultations and 80% of families who are referred to a paediatric respiratory clinic for chronic cough have sought medical advice five times or more (2). The majority of childhood coughs are secondary to an acute respiratory tract infection and will improve once the infection resolves, usually within 1 to 3 weeks. With pre-school children who may experience between 6 and 10 respiratory infections a year differentiating acute recurrent cough from chronic cough is key (Table 1). Chronic cough can significantly impact a family's quality of life, as it affects the child's sleep, school attendance and play. Parents experience distress and anxiety, worrying that the cough may lead to long-term chest damage or even death (3). This article aims to guide clinicians through the assessment of the child with a chronic cough. It will discuss identifying causes, use of first line investigations, initiating appropriate management and addressing parental anxiety and exacerbating factors (4,5).

Test-retest repeatability of child's respiratory symptoms and perceived indoor air quality - comparing self- and parent-administered questionnaires

Background

Questionnaires can be used to assess perceived indoor air quality and symptoms in schools. Questionnaires for primary school aged children have traditionally been parent-administered, but self-administered questionnaires would be easier to administer and may yield as good, if not better, information. Our aim was to compare the repeatability of self- and parent-administered indoor air questionnaires designed for primary school aged pupils.

Methods

Indoor air questionnaire with questions on child’s symptoms and perceived indoor air quality in schools was sent to parents of pupils aged 7–12 years in two schools and again after two weeks. Slightly modified version of the questionnaire was administered to pupils aged 9–12 years in another two schools and repeated after a week. 351 (52%) parents and 319 pupils (86%) answered both the first and the second questionnaire. Test-retest repeatability was assessed with intra-class correlation (ICC) and Cohen’s kappa coefficients (k).

Results

Test-retest repeatability was generally between 0.4–0.7 (ICC; k) in both self- and parent-administered questionnaire. In majority of the questions on symptoms and perceived indoor air quality test-retest repeatability was at the same level or slightly better in self-administered compared to parent-administered questionnaire. Agreement of self- and parent administered questionnaires was generally < 0.4 (ICC; k) in reported symptoms and 0.4–0.6 (ICC; k) in perceived indoor air quality.

Conclusions

Children aged 9–12 years can give as, or even more, repeatable information about their respiratory symptoms and perceived indoor air quality than their parents. Therefore, it may be possible to use self-administered questionnaires in future studies also with children.

Electronic supplementary material

The online version of this article (10.1186/s12890-018-0584-x) contains supplementary material, which is available to authorized users.

An underestimated cause of chronic cough: The Protracted Bacterial Bronchitis

Chronic cough in childhood is associated with a high morbidity and decreased quality of life. Protracted bacterial bronchitis (PBB) seems to be the second most common cause of chronic cough in children under 6 years of age. Its main clinical feature is represented by wet cough that worsens when changing posture and improves after the introduction of antibiotics. Currently, the mainstay of PBB treatment is a 2-week therapy with a high dose of antibiotics, such as co-amoxiclav, to eradicate the infection and restore epithelial integrity. It is very important to contemplate this disease in a child with chronic cough since the misdiagnosis of PBB could lead to complications such as bronchiectasis. Clinicians, however, often do not consider this disease in the differential diagnosis and, consequently, they are inclined to change the antibiotic therapy rather than to extend it or to add steroids. Data sources of this review include PubMed up to December 2016, using the search terms “child,” “chronic cough,” and “protracted bacterial bronchitis.”

Impact of Air Pollution on Age and Gender Related Increase in Cough Reflex Sensitivity of Healthy Children in Slovakia

BACKGROUND

Numerous studies show higher cough reflex sensitivity (CRS) and cough outcomes in children compared to adults and in females compared to males. Despite close link that exists between cough and environment the potential influence of environmental air pollution on age- and gender -related differences in cough has not been studied yet.

PURPOSE

The purpose of our study was to analyse whether the effects of exposure to environmental tobacco smoke (ETS) from parental smoking and PM10 from living in urban area are implied in age- and gender-related differences in cough outcomes of healthy, non-asthmatic children. Assessment of CRS using capsaicin and incidence of dry and wet cough was performed in 290 children (mean age 13.3 ± 2.6 years (138 females/152 males).

RESULTS

CRS was significantly higher in girls exposed to ETS [22.3 μmol/l (9.8-50.2 μmol/l)] compared to not exposed girls [79.9 μmol/l (56.4-112.2 μmol/l), p = 0.02] as well as compared to exposed boys [121.4 μmol/l (58.2-253.1 μmol/l), p = 0.01]. Incidence of dry cough lasting more than 3 weeks was significantly higher in exposed compared to not exposed girls. CRS was significantly higher in school-aged girls living in urban area [22.0 μmol/l (10.6-45.6 μmol/l)] compared to school-aged girls living in rural area [215.9 μmol/l (87.3-533.4 μmol/l); p = 0.003], as well as compared to teenage girls living in urban area [108.8 μmol/l (68.7-172.9 μmol/l); p = 0.007]. No CRS differences were found between urban and rural boys when controlled for age group. No CRS differences were found between school-aged and teenage boys when controlled for living area.

CONCLUSIONS

Our results have shown that the effect of ETS on CRS was gender specific, linked to female gender and the effect of PM10 on CRS was both gender and age specific, related to female gender and school-age. We suggest that age and gender related differences in incidence of cough and CRS might be, at least partially, ascribed to the effect of environmental pollutants. The role of age and gender in the effect of air pollution on cough strongly suggest some interplay of development with biological and behavioral factors.

Therapeutic effects of naringin in a guinea pig model of ovalbumin-induced cough-variant asthma

Naringin, a well known component isolated from Exocarpium Citri Grandis, has significant antitussive effects. Recently, Naringin exhibited novel anti-inflammatory effect in chronic inflammatory diseases. In this work, we firstly evaluated the effects of naringin on enhanced cough, airway hyper-responsiveness (AHR), and airway inflammation in an ovalbumin-induced experimental cough-variant asthma (CVA) model in guinea pigs. We investigated the effect of naringin (18.4 mg/kg, per os, single dose or consecutively) on cough to inhaled capsaicin after challenge with an aerosolized antigen in actively sensitized guinea pigs. The effect of naringin on AHR to inhaled methacholine was evaluated 24 h after cough determination. Airway inflammation was assessed via bronchoalveolar lavage fluid (BALF) cytology and lung histopathology. Naringin, given consecutively, significantly reduced ovalbumin-induced enhanced cough and AHR, inhibited the increases in the leukocytes, interleukin-4 (IL-4), IL-5, and IL-13 in BALF compared with the model group. Moreover, the pathologic changes in lung tissues were clearly ameliorated by naringin treatment. These results suggest that naringin may be a beneficial agent for CVA treatment.

Bacterial distribution in the lungs of children with protracted bacterial bronchitis

OBJECTIVES

Flexible bronchoscopy with bronchoalveolar lavage (FB-BAL) is increasingly used for the microbiological confirmation of protracted bacterial bronchitis (PBB) in children with a chronic wet cough. At our centre, when performing FB-BAL for microbiological diagnosis we sample 6 lobes (including lingula) as this is known to increase the rate of culture positive procedures in children with cystic fibrosis. We investigated if this is also the case in children with PBB.

METHODS

We undertook a retrospective case note review of 50 children investigated for suspected PBB between May 2011 and November 2013.

RESULTS

The median (IQR) age at bronchoscopy was 2.9 (1.7-4.4) years and the median (IQR) duration of cough was 11 (8.0-14) months. Positive cultures were obtained from 41/50 (82%) and 16 (39%) of these patients isolated ≥2 organisms. The commonest organisms isolated were Haemophilus influenzae (25 patients), Moraxella catarrhalis (14 patients), Staphylococcus aureus (11 patients) and Streptococcus pneumoniae (8 patients). If only one lobe had been sampled (as per the European Respiratory Society guidance) 17 different organisms would have been missed in 15 patients, 8 of whom would have had no organism cultured at all. The FB-BAL culture results led to an antibiotic other than co-amoxiclav being prescribed in 17/41 (41%) patients.

CONCLUSIONS

Bacterial distribution in the lungs of children with PBB is heterogeneous and organisms may therefore be missed if only one lobe is sampled at FB-BAL. Positive FB-BAL results are useful in children with PBB and can influence treatment.

Efficacy of procaterol combined with inhaled budesonide for treatment of cough-variant asthma

BACKGROUND AND OBJECTIVE

Procaterol, a selective, short-acting beta-2 adrenoceptor agonist, is effective in treating 'classical' asthma, but its efficacy for cough-variant asthma (CVA) is unknown. We evaluated the efficacy and safety of procaterol combined with budesonide for CVA.

METHODS

A prospective, randomized, double-blind, placebo-controlled, multicenter trial in China was conducted. One hundred and fifty-nine patients diagnosed with CVA (aged 18-75 years) were randomly divided into two groups to receive twice daily for 8 weeks, inhaled budesonide 100 μg plus either oral procaterol 25 μg or placebo. Primary and secondary efficacy variables were cough symptom severity scores and Leicester Cough Questionnaire (LCQ) life quality scores. Adverse events were also assessed.

RESULTS

The budesonide/placebo and budesonide/procaterol groups contained 80 and 78 participants (one excluded for later diagnosis of eosinophilic bronchitis), respectively, with similar baseline characteristics. Daily cough score declined during treatment in both groups and was lower in the budesonide/procaterol group at 8 (0.44 vs 0.73) and 10 (0.36 vs 0.69) weeks (P < 0.05). Compared with the budesonide/placebo group, the proportion of patients with a reduction of 3 points or greater (66% vs 42%) and that of patients scoring 0 points (63% vs 51%) was higher in the budesonide/procaterol group for daily cough scores (P < 0.05). At 8 weeks, LCQ score improvement was superior in the budesonide/procaterol group (38.94 ± 19.24 vs 32.71 ± 18.92; P < 0.05).

CONCLUSION

Procaterol combined with budesonide was well tolerated and effective at improving cough symptoms and quality of life in patients with CVA.

Recurrent wheeze and cough in young children: is it asthma?

A clinical diagnosis of asthma is often considered when a child presents with recurrent cough, wheeze and breathlessness. However, there are many other causes of wheeze in a young child. These range from recurrent viral infections to chronic suppurative lung disease, gastro-oesophageal reflux disease and rare structural abnormalities. Arriving at a diagnosis includes taking into consideration the symptomatology, triggers, atopic features, family history, absence of red flags and therapeutic trial, where indicated.

Evaluating cough assessment tools: a systematic review

BACKGROUND

Little is known about the comparative validity, reliability, or responsiveness of instruments for assessing cough frequency or impact, where the term impact encompasses both cough severity and the impact of cough on health-related quality of life.

METHODS

We conducted a systematic review to evaluate instruments that assess cough frequency or impact in adults, adolescents, and children with acute or chronic cough.

RESULTS

Seventy-eight studies were included, of which eight were randomized controlled trials and 70 were observational studies. In all age groups, audio and video electronic recording devices had good reliability compared with other methods of assessing cough frequency but had variable correlation with other cough assessments, such as visual analog scale scores, quality-of-life questionnaires, cough diaries, and tussigenic challenges. Among adult and adolescent patients, the Leicester Cough Questionnaire (LCQ) and the Cough-Specific Quality-of-Life Questionnaire (CQLQ) were valid and reliable, showing high intraclass and test-retest correlations. Among children, the Parent Cough-Specific Quality of Life Questionnaire and Pediatric Cough Questionnaire were valid and reliable.

CONCLUSIONS

Electronic recording devices can be valid assessments of cough frequency. The LCQ and CQLQ for adults and the Parent Cough-Specific Quality of Life questionnaire for children are valid instruments for assessing cough impact. There is limited but insufficient evidence to determine the reliability or concurrent validity of the different types of cough diaries or visual analog scale scores. There are also limited data to support the responsiveness of recording devices. There is good responsiveness data for the LCQ and CQLQ, but more evidence is needed.

Epidemiology of cough in relation to China

Cough is one of the most common complaints for which patients seek medical attention. Misdiagnosis and mistreatment of cough exist commonly in China. The prevalence of acute cough caused by upper airway infection fluctuates between 9% and 64% in the community, for chronic cough, the prevalence >10% in most surveys, ranging from 7.2%-33%. The common causes of chronic cough are upper airway cough syndrome (previously called as post nasal drip syndrome [PNDS]), cough variant asthma (CVA), gastroesophageal reflux related cough (GERD) and eosinophilic bronchitis (EB). There is a regional discrepancy regarding the prevalence of common causes of cough and distribution of gender among China, UK, USA, the most common cause of chronic cough in China are CVA, followed by UACS, EB and atopic cough (AC), the male is almost equal to female in numbers in China. The risk factors for cough includes cold air, smoking, environmental pollutants, noxious substances and allergens, and unreasonable diet habits.

Prevalence of respiratory signs and identification of risk factors for respiratory morbidity in Swedish Yorkshire terriers

Yorkshire terriers may be prone to respiratory disease; however, limited epidemiological information is available. A cross-sectional study design was used to compare the prevalence of respiratory signs in Yorkshire terriers with the prevalence in a population of dogs in general and to identify risk factors for respiratory clinical signs within the Swedish population of Yorkshire terriers. Data on clinical signs and risk factors were obtained from a questionnaire. The prevalence of respiratory signs in general (RS) was significantly higher among Yorkshire terriers compared with control dogs (RS 56.3 per cent and 23.0 per cent), and likewise more frequent respiratory signs (FRS) (26.0 per cent and 5.0 per cent). Age, sex and breed were shown to be significant risk factors, and an interaction between age and sex was discovered. The study indicated a sex ratio reversal in the prevalence of RS - the probability of females having RS increased with advancing age, while the probability for males was fairly constant.

Characteristics of Chinese patients with cough in primary care centre

Background

Cough is one of the most common respiratory symptoms and is well characterized in specialized cough clinics with high success rates of diagnosis and treatment. However, there is a paucity of data regarding cough in primary care settings. The present study aimed at investigating clinical epidemiology of cough through a national study of two questionnaire surveys sent to primary care physicians in China.

Methods

Approximately 18,000 subjects recruited were having daytime or night symptoms of cough and diagnoses of respiratory disease from February 2005 to April 2006 as Survey 1 and from June 2007 to December 2007 as Survey 2. Patients suffering from respiratory malignancy, hyperthyroidism, hypertension, heart disease, diabetes, severe hypohepatia or renal dysfunction, pregnancy, possible pregnancy or lactation, neutropenia were not eligible. Information regarding demography, history of allergies, symptomatic profile, treatment and curative effects for cough was elicited.

Results

8216 questionnaires were collected in Survey 1 and 9711 in Survey 2. The mean values of ages were 25.7 and 22.3 years old, respectively. Symptoms included expectoration (74% and 76%), wheeze (59% and 74%), breathlessness (22% and 26%), chest pain (9% and 13%) and fever (15% and 18%). About 15% and 23% patients had hypersusceptibility, of whom 6% to 17% had a family history. More than 50% of the cases had histories of allergic rhinitis, asthma, conjunctivitis or atopic dermatitis. Asthma, COPD, and bronchitis were dominant etiologies of cough. Procaterol or the combination of antibiotics and steroids were used as the treatment.

Conclusion

Causes and outcomes of cough differed with ages and time in this particular national study, while successful and precise diagnosis and management of cough in primary care settings need to be further improved in China.

Validation of a Pediatric Cough Questionnaire

We conducted a study to determine if a five-item pediatric cough questionnaire (PCQ) is a valid and reliable means of measuring cough-specific quality of life in children. The five questions, which are answered by the child's parent or caregiver, cover cough frequency (Q1), sleep disturbance of the child (Q2), sleep disturbance of the parent (Q3), cough severity (Q4), and the degree of bothersomeness to the child (Q5). Each of the five items was scored on a 6-point Likert scale. The PCQ was administered three times. The first occurred when the parent telephoned to schedule an appointment for the child at a pediatric pulmonology outpatient clinic for a chief complaint of cough. The second PCQ was administered within 2 weeks of the first but before any treatment had been instituted so that test-retest reliability could be assessed. Each child was then diagnosed and treated in accordance with standard care practices. The third PCQ was administered 3 weeks after the second to determine if it would accurately reflect the parent's perception of how the child's cough had changed following treatment. Also, at the second and third encounters, parents were asked to provide their global assessment of whether their child's cough had improved, worsened, or stayed the same since the previous encounter. The parents of 120 children (70 boys and 50 girls; mean age: 6.8 yr) completed all three PCQs. Test-retest reliability was established (p < 0.001) for each of the five PCQ questions by Spearman correlation analysis (Q1: r = 0.5; Q2: r = 0.38; Q3: r = 0.42; Q4: r = 0.53; Q5: r = 0.5). Other statistical analyses confirmed the PCQ's internal consistency, discriminant validity, and convergent validity. Based on our findings, we conclude that the PCQ is a valid and reliable instrument with which to follow children with chronic cough longitudinally.

Tobacco smoke exposure in hospitalised Aboriginal children in Central Australia

AIM

Child exposure to tobacco smoke is detrimental to health. Australian Aboriginal people have a higher rate of cigarette smoking compared with the national average. Thus, we aim to measure the proportion of children admitted to Alice Springs Hospital who are exposed to tobacco smoke at home, to correlate this with prevalence of regular cough and gauge smokers' interest in quitting.

METHOD

A questionnaire was administered verbally to carers of children admitted to Alice Springs Hospital, November 2006 to January 2007. Main outcome measures were presence of a smoker at home and presence of a regular cough. We measured the interest of carers and speculated interest of other smokers in quitting. Eighty-two questionnaires were completed (60% of children admitted during the study period). Eighty-nine per cent of children were Aboriginal.

RESULTS

As so few non-Aboriginal children were included in the study, their results were not included in analysis. Sixty-four per cent of children lived with at least one smoker. Seventy per cent of children exposed to smoke at home lived with more than one smoker. Point prevalence of reported regular cough was 33%. Forty-three per cent of children who lived with at least one smoker had regular cough compared with 13% in those who did not (P= 0.035). The rate ratio for regular cough when living with a smoker versus when not living with a smoker was 2.77 (95% confidence interval: 1.06-7.23). Forty-two per cent of the smokers expressed interest in quitting.

CONCLUSION

It is concerning that the majority of hospitalised children were exposed to tobacco smoke at home, while fewer than half of smokers were interested in quitting.

Cough

The management of cough in children should be etiologically based. This requires that all children with cough should be carefully evaluated and managed differently than adults because the etiologic factors and treatment in children are significantly different than that in adults. In all children with cough, exacerbation factors should be sought and intervention options for cessation advised or initiated. Parental expectations and specific concerns should also be sought and addressed.

The International Study of Wheezing in Infants: questionnaire validation

BACKGROUND

There are no internationally validated questionnaires to investigate the prevalence of infant wheezing. This study was undertaken to validate a questionnaire for the International Study on the Prevalence of Wheezing in Infants (Estudio Internacional de Sibilancias en Lactantes, EISL).

MATERIAL AND METHODS

Construct and criterion validity were tested for the question 'Has your baby had wheezing or whistling in the chest during his/her first 12 months of life?'. Construct validity (i.e. the ability of parents and doctors to refer to the same symptoms with the same words) was tested in a sample of 50 wheezing and 50 non-wheezy infants 12-15 months of age in each of 10 centres from 6 different Spanish- or Portuguese-speaking countries. Criterion validity (i.e. the ability of parents to correctly detect the symptom in the general population) was evaluated in 2 samples (Santiago, Chile and Cartagena, Spain) of 50 wheezing and 50 non-wheezing infants (according to parents) of the same age, randomly selected from the general population, who were later blindly diagnosed by a paediatric pulmonologist.

RESULTS

Construct validity was very high (kappa test: 0.98-1) in all centres. According to Youden's index, criterion validity was good both in Cartagena (75.5%) and in Santiago (67.0%). Adding questions about asthma medication did not improve diagnosis accuracy.

CONCLUSIONS

The EISL questionnaire significantly distinguished wheezy infants from healthy ones. This questionnaire has a strong validity and can be employed in large international multicentre studies on wheezing during infancy.

Clinical assessment of chronic cough severity

The assessment of cough severity solely through consultation with the patient is limited by its subjective nature and variability of physician judgement. The assessment of cough has been hampered by a paucity of objective tools, those available have been poorly validated, non-standardized and are impractical for clinical use. Recent developments have overcome some of these problems and a variety of tools can now be used to assess cough that include visual analogue scales (VAS), quality-of-life questionnaires, cough reflex sensitivity measurement and automated cough frequency monitors. These tools can be used to validate the presence of cough and assess response to therapy. They will also have an important role in clinical trials.

A comparison of risk factors for wheeze and recurrent cough in preschool children

In a study of 2,978 Danish children aged 5 years from two suburban counties of Copenhagen, carried out in 1998, the authors compared risk factor profiles for wheeze and recurrent cough without wheeze by using polytomous logistic regression to clarify whether the two conditions are likely to have the same etiology. Data were obtained 1) by a mailed parental questionnaire (International Study of Asthma and Allergies in Childhood questions and supplementary questions on cough, sociodemography, perinatal factors, and environmental exposure); 2) through general practitioners (familial allergic disease); and 3) from the National Medical Birth Register (birth weight). Wheeze (WH) was defined as more than one episode of wheeze within the last 12 months (irrespective of cough status) and recurrent cough without WH (RC) as cough occurring outside colds and usually lasting for periods of more than 1 week in children with no more than one attack of wheeze within the last 12 months. Risk factors for comparison were selected as those that, after repeated stepwise logistic regression, remained significant for children with WH or RC. Significant differences were found for gender (p = 0.003), gestational age (p = 0.0002), maternal history of asthma (p = 0.0008), and standard of housing condition (p = 0.04)-all risk factors for WH but not RC. Results may suggest that the two conditions have different etiologies.

Cough . 2: Chronic cough in children

Chronic cough is a common problem in childhood. Viral infections are the most prevalent cause, but other rarer disorders should be excluded whenever cough appears unusually severe and/or frequent, and when there is evidence of failure to thrive and growth retardation. The younger the child, the more the need to exclude underlying disease at an early stage. Passive smoking is an important contributor to chronic cough in children. Chronic productive cough with purulent sputum is always reason for concern in children and is not common as a symptom of asthma. More or less specific diagnoses in children include cystic fibrosis, aspirated foreign body, congenital anatomic abnormalities and primary ciliary dyskinesia.

Psychogenic cough in a schoolboy: evaluation using an ambulatory cough recorder

Psychogenic cough occurs most commonly in patients under 18 years of age. Making the diagnosis on clinical features alone is problematic, and it is usually a diagnosis of exclusion after several negative clinical investigations. We report on the case of a 13-year-old schoolboy with a 3-month history of persistent dry cough with no other associated symptoms. Clinical examination and investigations revealed no abnormality, and empirical trials of antiasthma and antacid medications proved unsuccessful. An objective assessment of his cough frequency was made using an ambulatory cough monitor. A large number of cough episodes were recorded during the day, but during the time he was in bed there were very few episodes recorded. This suggested a diagnosis of psychogenic cough, and he underwent behavior modification therapy under the guidance of a clinical psychologist, with good result. Objective cough monitoring may therefore improve the evaluation and management of chronic cough.

A parent completed questionnaire to describe the patterns of wheezing and other respiratory symptoms in infants and preschool children

AIM

To develop a standardised and validated respiratory symptom questionnaire for use in epidemiological or follow up studies in infants and preschool children.

METHODOLOGY

After initial design and development, the questionnaire was administered to two cohorts of subjects, one recruited from a respiratory clinic and the other from a postnatal ward. The two cohorts then repeated the questionnaire, two weeks apart. The qualities of the questionnaire were assessed.

RESULTS

Response rate to the initial questionnaire was 100% for the clinic based cohort and 64% for postnatally recruited families (total number of subjects 114). Questions showed good to moderate short term reliability (weighted kappa scores 0.47-0.7; average correct classification rates 0.74-0.91). Four domain concept scores showed excellent internal consistency (Cronbach alpha scores 0.87-0.95). Using principal component factor analysis, four new domains were devised showing acceptable construct validity and internal consistency. Criterion validity was assessed using a respiratory physician based diagnosis of asthma (RPBDA) as the gold standard for comparison. All eight scales in the questionnaire could significantly distinguish between infants with RPBDA and well or mildly symptomatic subjects.

CONCLUSION

We have developed a practical, acceptable questionnaire with eight concept domains for use in infants and preschool children. The questionnaire has strong construct validity and internal consistency with good short term reliability of questions. More detailed study of criterion validity and the responsiveness of the questionnaire is required using a larger population and including children with the different phenotypes of wheezy illness.

Issues in identifying asthma and estimating prevalence in an urban school population

This article first presents salient issues related to identifying children in urban schools who might benefit from asthma services. It discusses a brief questionnaire for identifying cases and problems in estimating asthma prevalence. Subsequently, results of case detection in 14 urban schools are presented and discussed in light of these issues. The questionnaire was employed with parents of 4,653 African-American children in Detroit. Results suggest that determining number, type, and frequency of symptoms may be necessary to ascertain prevalence of asthma. Using only number and type produced a rate of asthma of 25%. Adding frequency provided a more conservative estimate of 19%. About 9% of children exhibiting symptoms of asthma had no physician diagnosis. Only 25% with symptoms reflecting mild persistent, 35% with moderate persistent, and 26% with severe persistent disease had prescriptions for anti-inflammatory medicine. Further, 23% of children with asthma-like symptoms had no prescription for asthma medicine of any type.

CONCLUSIONS

(1) low-cost procedures can be used in schools to identify children with suspected undiagnosed and undertreated asthma; (2) prevalence estimates for asthma in the group of urban school children studied are among the highest in the United States; and (3) asthma is undertreated in this sample.

Exhaled nitric oxide levels in atopic children: relation to specific allergic sensitisation, AHR, and respiratory symptoms

BACKGROUND

Exhaled nitric oxide (eNO), which has been proposed as a measure of airway inflammation, is increased in atopic subjects. This raises the question of whether eNO provides any additional information about airway inflammation in asthmatic subjects, other than as a marker for atopy. A study was undertaken to determine whether eNO levels in a population of atopic children are associated with sensitisation or natural exposure to specific allergens, and to examine the relationship between eNO, airway responsiveness, and current respiratory symptoms.

METHODS

Exhaled NO and airway responsiveness to histamine were measured in winter and in summer in 235 children aged 8-14 years who had been classified as atopic by skin prick testing. Current respiratory symptoms, defined as wheeze or cough during the month preceding the test, were measured by a parent completed questionnaire. Airway hyperresponsiveness (AHR) was defined as a dose response ratio (DRR) of >8.1 (% fall in forced expiratory volume in 1 second (FEV(1))/micromol + 3).

RESULTS

Sensitisation to house dust mite was associated with raised eNO levels in winter while sensitisation to Cladosporium was associated with raised eNO levels in both winter and summer. Grass pollen sensitisation was not associated with raised eNO levels in either season. Exhaled NO correlated significantly with DRR histamine (r=0.43, p<0.001) independently of whether the children had current symptoms or not. In children with current wheeze, those with AHR had eNO levels 1.53 (95% CI 1.41 to 1.66) times higher than those without AHR (p=0.006). Neither DRR (p=1.0) nor eNO levels (p=0.92) differed significantly between children with or without persistent dry cough in the absence of wheeze.

CONCLUSIONS

In atopic children, raised eNO levels are associated with sensitisation to perennial allergens, but not to seasonal allergens such as grass pollen. In this population, an increase in eNO is associated with AHR and current wheezing, suggesting that eNO is more than just a marker for atopy.

Evaluation of a cough-specific quality-of-life questionnaire

STUDY OBJECTIVE

To psychometrically evaluate a cough-specific quality-of-life questionnaire (CQLQ) in adults.

DESIGN

Prospective evaluation of CQLQ using three different cohorts of adult subjects with cough.

SETTING

Academic tertiary-care ambulatory medical facilities.

PARTICIPANTS

One hundred fifty-four subjects complaining of chronic cough, 30 of acute cough, and 31 smokers with cough.

INTERVENTIONS

Self-administration of the CQLQ in acute coughers, smokers, and chronic coughers before and after therapy.

MEASUREMENTS

Psychometric analyses including factor analysis (FA), and assessments of reliability and validity.

RESULTS

Acute and chronic cough data were subjected to FA, and the Cronbach alpha and interitem correlations were computed. FA of chronic and acute cough data (n = 184) revealed six subscales. The Cronbach alpha for the total CQLQ was 0.92, and it was 0.62 to 0.86 (mean, 0.76) for the six subscales. Interitem correlations for the total CQLQ ranged from -0.06 to 0.72, with a mean of 0.28. Test-retest reliability in 52 chronic coughers demonstrated nonsignificant changes with readministration of the questionnaire, and the intraclass correlation for total CQLQ was 0.89, and for the subscales the range was 0.75 to 0.93. Analysis of variance followed by tests of contrasts among all possible pairings of chronic coughers, acute coughers, and smokers showed significant differences (p < or = 0.001) among the groups. Posttreatment cure scores were significantly lower (p < or = 0.001) than pretreatment scores in 24 chronic coughers.

CONCLUSIONS

The 28-item CQLQ has dimensionality that is consistent with a cough-specific quality-of-life instrument. It is a valid and reliable method by which to assess the impact of cough on the quality of life of chronic and acute coughers, and the efficacy of cough therapies in chronic coughers.

Assessing the evidence for remodelling of the airway in asthma

Asthma is now described as being characterized by reversible airflow obstruction, with bronchial inflammation and tissue remodelling of the airway wall. The description of remodelling has been usefully invoked to account for a component of airflow obstruction that is unresponsive to usual bronchodilator therapy. It is crucial to examine critically the evidence for this view, particularly the quantitation of specific changes in the epithelium, mucus glands, cell infiltrate, collagen, vessels and smooth muscle of the bronchial wall. The useful tools of immunohistochemistry and molecular biology combined with airway biopsy and well-designed clinical trials will be essential to determine the specific roles of cells and cytokines in airway remodelling in asthma.

[Definition and nosological aspects of chronic cough in children]

Cough is a physiological reflex occurring when sensitive receptors located in upper airways and the larynx are activated. By definition a 'chronic cough' lasts at least 3 weeks. An analysis of clinical characteristics is essential for setting up the diagnosis and giving correct treatment. We can individualize three mainly clinical aspects: the young child of less than 3 years of age, the nocturnal cough and the productive cough. The 'variant of asthma' cough is a common problem among all ages that frequently goes unrecognized. Any patient with dry nocturnal coughing that lasts more than three weeks should have an empiric bronchodilator treatment. The prognosis is on the whole favourable.

Validation of the Brief Pediatric Asthma Screen

STUDY OBJECTIVES

The purpose of this study was to confirm the validity of a brief screen for pediatric asthma in schools.

BACKGROUND

Asthma is the most common chronic disease of childhood, yet the frequency with which this condition is recognized among school-aged children varies widely. Several methods are used to increase the accuracy of detection of asthma, but many are cumbersome and difficult to apply on a large scale.

DESIGN

We elected to validate a five-question instrument, the Brief Pediatric Asthma Screen (BPAS), to screen for the presence of asthma among children attending school in Region 5 of the Chicago school district, where the schools report a 2.7% frequency of asthma. The questionnaire was distributed to the parents of grade-school children at the time of report-card pick-up.

SETTING

A clinical assessment was performed on a selected group of children whose parents completed the questionnaire in a school and in a hospital outpatient clinic.

PARTICIPANTS

Of 4,147 questionnaires that we distributed, 1,796 (43%) were returned. We excluded 341 children (19% of the total sample) whose parents reported that they had been diagnosed with asthma. The remaining pool indicated that the children of 183 responders (10%) had symptoms suggestive of asthma, while 1,272 parents (71%) indicated that their children did not have symptoms of asthma.

MEASUREMENTS AND RESULTS

We selected 90 of the respondents who did not indicate that their children had a diagnosis of asthma. Of this group, 81 completed the validation, in which their responses suggested symptoms of asthma (n = 34) or no asthma symptoms (n = 47). The children of these respondents were given a blinded clinical evaluation consisting of history, physical examination, and spirometry. The survey demonstrated a sensitivity of 75% and a specificity of 81.2% for the presence of asthma among those who were unaware of the diagnosis.

CONCLUSIONS

The BPAS is brief, can be filled out by parents, and appears accurate in detecting asthma.