Stability of respiratory symptoms in unlabelled wheezy illness and nocturnal cough

OBJECTIVE: To assess the natural history of respiratory symptoms not labelled as asthma in primary schoolchildren. DESIGN: Repeat questionnaire survey of subgroups identified from a previous questionnaire survey after a two year delay. SUBJECTS: The original population of 5321 Sheffield children aged 8-9 years yielded 4406 completed questionnaires in 1991(82.8%). After excluding children with a label of asthma, there were 370 children with current wheeze, 129 children with frequent nocturnal cough, and a random sample of 222 children with minor cough symptoms and 124 asymptomatic children. RESULTS: Response rates in the four groups were 233 (63.0%), 77 (59.7%), 160 (72.1%), and 90 (72.6%) respectively. Of those who initially wheezed, 114 (48.9%) had stopped wheezing and 42 (18.0%) had been labelled as having asthma. Those with more frequent wheezing episodes (p < 0.02) and a personal history of hay fever (p < 0.01) in 1991 were more likely to retain their wheezy symptoms. In the children with frequent nocturnal cough in 1991, 20.1% had developed wheezing, 42.9% had a reduced frequency of nocturnal coughing, and 14.2% had stopped coughing altogether two years later. One sixth had been labelled as having asthma. Children with nocturnal cough were more likely to develop wheezing if they had a family history of atopy (p = 0.02). Only 3.8% and 3.3% of those with minimal cough and no symptoms respectively in 1991 had developed wheeze by 1993 (1.9% and 1.0% labelled as asthma). CONCLUSIONS: Most unlabelled recurrent respiratory symptoms in 8-10 year olds tend to improve. Unlabelled children who have persistent symptoms have other features such as frequent wheezing attacks and a family or personal history of atopy. If a screening questionnaire were to be used to identify such children, a combination of questions should be employed.     

Stability of respiratory symptoms in unlabelled wheezy illness and nocturnal cough.

OBJECTIVE: To assess the natural history of respiratory symptoms not labelled as asthma in primary schoolchildren. DESIGN: Repeat questionnaire survey of subgroups identified from a previous questionnaire survey after a two year delay. SUBJECTS: The original population of 5321 Sheffield children aged 8-9 years yielded 4406 completed questionnaires in 1991(82.8%). After excluding children with a label of asthma, there were 370 children with current wheeze, 129 children with frequent nocturnal cough, and a random sample of 222 children with minor cough symptoms and 124 asymptomatic children. RESULTS: Response rates in the four groups were 233 (63.0%), 77 (59.7%), 160 (72.1%), and 90 (72.6%) respectively. Of those who initially wheezed, 114 (48.9%) had stopped wheezing and 42 (18.0%) had been labelled as having asthma. Those with more frequent wheezing episodes (p < 0.02) and a personal history of hay fever (p < 0.01) in 1991 were more likely to retain their wheezy symptoms. In the children with frequent nocturnal cough in 1991, 20.1% had developed wheezing, 42.9% had a reduced frequency of nocturnal coughing, and 14.2% had stopped coughing altogether two years later. One sixth had been labelled as having asthma. Children with nocturnal cough were more likely to develop wheezing if they had a family history of atopy (p = 0.02). Only 3.8% and 3.3% of those with minimal cough and no symptoms respectively in 1991 had developed wheeze by 1993 (1.9% and 1.0% labelled as asthma). CONCLUSIONS: Most unlabelled recurrent respiratory symptoms in 8-10 year olds tend to improve. Unlabelled children who have persistent symptoms have other features such as frequent wheezing attacks and a family or personal history of atopy. If a screening questionnaire were to be used to identify such children, a combination of questions should be employed.     

The management of persistent isolated cough in childhood

Persistent isolated cough is a distinct clinical entity, separate from asthma. It is empirically defined as a non-productive cough of at least 3 weeks duration, in the absence of any identifiable respiratory disease. It is usually nocturnal. An accurate diagnosis rests on a good history and examination. Investigations are rarely needed. Management consists of reassuring parents that the symptom is predominantly self-limiting, and will not result in long-term morbidity.     

Validity and reliability of acoustic analysis of respiratory sounds in infants

Objective: To investigate the validity and reliability of computerised acoustic analysis in the detection of abnormal respiratory noises in infants. Methods: Blinded, prospective comparison of acoustic analysis with stethoscope examination. Validity and reliability of acoustic analysis were assessed by calculating the degree of observer agreement using the κ statistic with 95% confidence intervals (CI). Results: 102 infants under 18 months were recruited. Convergent validity for agreement between stethoscope examination and acoustic analysis was poor for wheeze (κ = 0.07 (95% CI, –0.13 to 0.26)) and rattles (κ = 0.11 (–0.05 to 0.27)) and fair for crackles (κ = 0.36 (0.18 to 0.54)). Both the stethoscope and acoustic analysis distinguished well between sounds (discriminant validity). Agreement between observers for the presence of wheeze was poor for both stethoscope examination and acoustic analysis. Agreement for rattles was moderate for the stethoscope but poor for acoustic analysis. Agreement for crackles was moderate using both techniques. Within-observer reliability for all sounds using acoustic analysis was moderate to good. Conclusions: The stethoscope is unreliable for assessing respiratory sounds in infants. This has important implications for its use as a diagnostic tool for lung disorders in infants, and confirms that it cannot be used as a gold standard. Because of the unreliability of the stethoscope, the validity of acoustic analysis could not be demonstrated, although it could discriminate between sounds well and showed good within-observer reliability. For acoustic analysis, targeted training and the development of computerised pattern recognition systems may improve reliability so that it can be used in clinical practice.     

Predicting clinically significant lower respiratory tract illness in childhood following mild bronchiolitis

A historical cohort study was conducted to measure lower respiratory tract illness (LRTI) up to nine years following mild bronchiolitis and to discover attributes that predict an increased risk for LRTI in childhood. The hypothesis assessed was that the occurrence of bronchiolitis predicts LRTI following the second birthday (childhood LRTI) after adjusting for potentially confounding variables such as a family history of respiratory allergy. Fifty-three children (index subjects) who were seen for bronchiolitis at a suburban community pediatric practice were compared on the basis of childhood LRTI with a control group of 159 children. Chart review, when children were a mean of 8 years old, determined the frequency of childhood LRTI. The mean frequency of childhood LRTI was greater in index subjects than in control subjects (1.62 vs 0.98). This difference remained after adjusting for potentially confounding variables. The yearly occurrence of any LRTI was significantly more common in index subjects through the third year of life (38% vs 15%). A tendency for a more common occurrence of any LRTI was noted through the fifth year (25% vs 16%), but not thereafter. Further analysis of index subjects disclosed that only those who experienced a subsequent LRTI before the second birthday were at an increased risk for the development of childhood LRTI.     

Validity and reliability of acoustic analysis of respiratory sounds in infants.

OBJECTIVE: To investigate the validity and reliability of computerised acoustic analysis in the detection of abnormal respiratory noises in infants. METHODS: Blinded, prospective comparison of acoustic analysis with stethoscope examination. Validity and reliability of acoustic analysis were assessed by calculating the degree of observer agreement using the kappa statistic with 95% confidence intervals (CI). RESULTS: 102 infants under 18 months were recruited. Convergent validity for agreement between stethoscope examination and acoustic analysis was poor for wheeze (kappa = 0.07 (95% CI, -0.13 to 0.26)) and rattles (kappa = 0.11 (-0.05 to 0.27)) and fair for crackles (kappa = 0.36 (0.18 to 0.54)). Both the stethoscope and acoustic analysis distinguished well between sounds (discriminant validity). Agreement between observers for the presence of wheeze was poor for both stethoscope examination and acoustic analysis. Agreement for rattles was moderate for the stethoscope but poor for acoustic analysis. Agreement for crackles was moderate using both techniques. Within-observer reliability for all sounds using acoustic analysis was moderate to good. CONCLUSIONS: The stethoscope is unreliable for assessing respiratory sounds in infants. This has important implications for its use as a diagnostic tool for lung disorders in infants, and confirms that it cannot be used as a gold standard. Because of the unreliability of the stethoscope, the validity of acoustic analysis could not be demonstrated, although it could discriminate between sounds well and showed good within-observer reliability. For acoustic analysis, targeted training and the development of computerised pattern recognition systems may improve reliability so that it can be used in clinical practice.     

The hypersensitive respiratory system in childhood

Aetiological factors and mechanisms of bronchial hyperreactivity are discussed. The hypothesis of increased permeability of the bronchial mucosa--caused by either endogenous or exogenous stimuli--as the most plausible explanation for the connection between hyperreactivity and childhood asthma bronchiale is emphasized. Finally, unspecific inhalative provocation tests for proof of bronchial hyperreactivity, its indications and contraindications as well as the criteria of judgement are mentioned.     

Prognostic values of specific respiratory sounds for asthma in adolescents

Childhood wheezing is a common condition associated with asthma, but the term is often misapplied. The present study aimed to investigate the prognostic values of specific respiratory sounds for asthma onset in adolescence. In a prospective study, six specific respiratory sounds were evaluated for their prediction of asthma. Parents were asked for respiratory sounds of their initially asthma-free children and to describe them in specified terms. Self-reported doctor-diagnosed asthma of 1,569 children aged 5 to 14 years from Germany was assessed at baseline and at follow-up for up to 12 years later. Except for ‘ronchus’ (17%), reported ‘gasp’ and ‘whimper’ had the highest positive predictive values of 15% and 11%, respectively. These sounds also showed the greatest increase in asthma incidence (odds ratio = 3.18; 95%CI, 1.46–6.94 and odds ratio = 2.09; 95%CI, 1.00–4.37). It could be shown that from six respiratory sounds, ‘gasp’ and ‘whimper’ were the expressions with the best prediction for asthma onset. This study suggests that parents can sensibly distinguish between respiratory sounds and that it is important to specify breathing sounds, as not all are good predictors for asthma.     

Pediatric HIV disease. The newest chronic illness of childhood

HIV disease has emerged as a major chronic illness of childhood. Children with HIV infection and children with other chronic health impairments have much in common, including the need for comprehensive, multidisciplinary, coordinated care that includes special attention to the psychosocial effects on the child and family. However, because the mother and often the father and siblings share this lethal viral infection, the impact of HIV disease upon the family surpasses that of virtually all other chronic conditions. This is compounded by the association of the disease with drug use, its preponderance among the most disenfranchised populations in the United States, and the persistent public fear and discrimination surrounding AIDS. We have made substantial progress already in the medical management of this infection, and while we await the development of more effective therapies, we already have the tools and knowledge in hand to help these families.