W.M.C. van Aalderen

Definition, assessment and treatment of wheezing disorders in preschool children: an evidence-based approach

There is poor agreement on definitions of different phenotypes of preschool wheezing disorders. The present Task Force proposes to use the terms episodic (viral) wheeze to describe children who wheeze intermittently and are well between episodes, and multiple-trigger wheeze for children who wheeze both during and outside discrete episodes. Investigations are only needed when in doubt about the diagnosis. Based on the limited evidence available, inhaled short-acting β2-agonists by metered-dose inhaler/spacer combination are recommended for symptomatic relief. Educating parents regarding causative factors and treatment is useful. Exposure to tobacco smoke should be avoided; allergen avoidance may be considered when sensitisation has been established. Maintenance treatment with inhaled corticosteroids is recommended for multiple-trigger wheeze; benefits are often small. Montelukast is recommended for the treatment of episodic (viral) wheeze and can be started when symptoms of a viral cold develop. Given the large overlap in phenotypes, and the fact that patients can move from one phenotype to another, inhaled corticosteroids and montelukast may be considered on a trial basis in almost any preschool child with recurrent wheeze, but should be discontinued if there is no clear clinical benefit. Large well-designed randomised controlled trials with clear descriptions of patients are needed to improve the present recommendations on the treatment of these common syndromes.

Re: Oral desensitization as a useful treatment in 2‐year‐old children with cow's milk allergy

Cite this as: L. Hulshof, A. A. Schoemaker, N. C. M. Petrus, W. M. C. van Aalderen and A. B. Sprikkelman, Clinical & Experimental Allergy, 2011 (41) 1815–1816.

Incidence and short-term outcome of acute lung injury in mechanically ventilated children

The aim of this study was to determine the incidence and short-term outcome of mechanically ventilated children suffering from acute lung injury (ALI) on a paediatric intensive care unit (PICU). Between January 1 1998 and January 1 2000, all mechanically ventilated children were evaluated using the criteria of an American-European Consensus Conference. Of the 443 children eligible for analysis, 44 (9.9%) were diagnosed as suffering from ALI. Of these, 79.5% developed the acute respiratory distress syndrome (ARDS); 54.5% (24 of 44) fulfilled the ARDS criteria at inclusion and 25% (11 of 44) later. PICU mortality for ALI was 27.3% (12 of 44) and within the ARDS subgroup 31.4% (11 of 35). Of the 12 children who died, 11 had ARDS; the main cause of death was cerebral damage (seven of 12). Acute lung injury and acute respiratory distress syndrome are rare diseases on apaediatric intensive care unit with a high mortality. Most of the children with acutelung injury develop acute respiratory distress syndrome. In the acute respiratory distress syndrome subgroup, mortality is higher than in the acute lung injury nonacute respiratory distress syndrome subgroup. Further investigations should confirm prognostic factors (e.g. respiratory parameters) for prediction of outcome.

Synbiotics prevent asthma-like symptoms in infants with atopic dermatitis

To cite this article: van der Aa LB, van Aalderen WMC, Heymans HSA, Henk Sillevis Smitt J, Nauta AJ, Knippels LMJ, Ben Amor K, Sprikkelman AB, the Synbad Study Group. Synbiotics prevent asthma‐like symptoms in infants with atopic dermatitis. Allergy 2011; 66: 170–177.

Effect of a new synbiotic mixture on atopic dermatitis in infants: a randomized-controlled trial.

Background Clinical trials investigating the therapeutic effect of probiotics on atopic dermatitis (AD) show inconsistent results. Better results can possibly be achieved by combining probiotics with prebiotics, i.e. synbiotics.

Viral lower respiratory tract infection in infants and young children

Viruses are the most common cause of lower respiratory tract disease in infants and young children and are a major public health problem in this age group. The novel variant of coronavirus that is associated with the worldwide outbreak of severe acute respiratory syndrome and human metapneumovirus, a recently identified new respiratory pathogen, have stressed the continuing importance of viral respiratory infections over the whole age spectrum. Costs attributable to viral lower respiratory tract infections in both outpatient and inpatient settings are an important burden on national healthcare budgets.1 Each year approximately 3% of all children less than 1 year of age need to be admitted to hospital with moderate or severe viral lower respiratory tract infection.2 This review gives an update of viral lower respiratory tract infection in infants and young children, with special emphasis on treatment and prevention. We gathered information from our own experience and by reading relevant literature on viral respiratory infections in infants and children obtained by searching Medline and the Cochrane database. Much literature is available on the topic, so we based our review on well designed major observational studies, controlled trials, and systematic reviews. We consulted the websites of the World Health Organization and the Centers for Disease Control for the most recent information on severe acute respiratory syndrome. A great variety of viruses can cause lower respiratory tract disease in children—for example, respiratory syncytial virus, influenza viruses, parainfluenza viruses, rhinovirus, adenovirus, and the recently identified human metapneumovirus.3,w1,w2 Although most respiratory viral infections occur throughout the year, seasonal variation (in a worldwide comparable pattern) is obvious for certain viruses, such as respiratory syncytial virus and influenza virus (figure). Epidemiology of respiratory syncytial virus, influenza A, adenovirus, and parainfluenza virus in the Netherlands, 1997-2003 ### Respiratory syncytial virus and influenza viruses Worldwide, respiratory syncytial virus is …

Dexamethasone for treatment of patients mechanically ventilated for lower respiratory tract infection caused by respiratory syncytial virus

Background: A study was undertaken to evaluate the efficacy of dexamethasone in patients mechanically ventilated for lower respiratory infection caused by respiratory syncytial virus (RSV-LRTI). Methods: In a multicentre randomised controlled trial patients were randomised to receive either intravenous dexamethasone (0.15 mg/kg 6 hourly for 48 hours) or placebo. End points were the duration of mechanical ventilation, length of stay (LOS) in the pediatric intensive care unit (PICU) and in hospital, and the duration of supplemental oxygen administration. Results: Thirty seven patients received dexamethasone and 45 received placebo. There was no significant difference in any of the end points between the two groups. In a post hoc analysis patients were stratified into those with mild gas exchange anomalies (Pao2/Fio2 >200 mm Hg and/or mean airway pressure ⩽ 10 cm H2O, bronchiolitis group) and those with severe gas exchange anomalies (Pao2/Fio2 ⩽200 mm Hg and mean airway pressure >10 cm H2O, pneumonia group). In the 39 patients with bronchiolitis the duration of mechanical ventilation was 4.3 days shorter in the dexamethasone group than in the placebo group (4.9 v 9.2 days, 95% CI −7.8 to −0.8, p=0.02) and the duration of supplemental oxygen was 3.6 days shorter (7.7 v 11.3 days, 95% CI −8.0 to −0.1, p=0.048). No differences in end points were found in the pneumonia group. Conclusions: Dexamethasone had no beneficial effect in patients mechanically ventilated for RSV-LRTI but was found to have a beneficial effect in patients with bronchiolitis.

Severity scoring of atopic dermatitis: a comparison of three scoring systems

In studies on atopic dermatitis (AD), different scoring systems are used to evaluate the severity of the disease. The objective of this study was to investigate agreement between observers in the assessment of the overall severity of AD, and interobserver variation in the assessment of severity of AD for each scoring item separately, using the Simple Scoring System (SSS), the Scoring Atopic Dermatitis (SCORAD) index, and the Basic Clinical Scoring System (BCSS), and, furthermore, to investigate agreement between these three scoring systems in the assessment of the overall severity of AD. Eighty‐two patients (42 male) with AD, mean age 13.4 years (range 0.2−67.0), were included. Agreement between observers in assessing the overall AD severity scores, and interobserver variation in assessing AD severity of each scoring item separately were determined in 34 of these 82 patients by two physicians scoring the severity of AD by the three scoring systems. To determine agreement between the scoring systems, one physician scored the severity of AD in all patients with the three scoring systems. Agreement between observers and agreement between the three scoring systems was calculated by Cohens kappa (κ) and by the measure of agreement according to Bland & Altaian. κ>0.4 represents fair agreement; κ>0.75 excellent agreement. In addition, interobserver variation for each scoring item separately was calculated by the Wilcoxon signed rank test. The mean differences (d) and the limits of agreement (d±2 SD of the differences) between observers by the SSS and the SCORAD were −0.82±5.58 and −0.28±7.49, respectively. κ between observers for the BCSS was 0.90 (95% CI 0.79−1.03). By the SSS, significant interobserver variation was found in assessing the severity of excoriations (P=0.02) and scales (P=0.02). By the SCORAD, significant interobserver variation was found in assessing the severity of edema/papulation (P=0.04), erythema (P=0.04), and excoriations (P=0.01). No significant interobserver variation was found in assessing the extent of AD. The mean difference and the limits of agreement between the SSS and the SCORAD were −4.17±9.52. k between the SSS and the BCSS was 0.21 (95% CI 0.09−0.33), and k between the SCORAD and the BCSS was 0.38 (95% CI 0.26−0.51). We found good agreement between observers assessing the overall severity of AD in the lower and higher scoring rates by the SSS and the SCORAD, and excellent agreement by the BCSS. Significant interobserver variation was found on the isolated intensity items scales, excoriations, edema/papulation, and erythema. We found poor agreement between the three scoring systems in assessing the overall severity of AD, indicating that the SSS, the SCORAD, and the BCSS cannot be used interchangeably to assess the overall severity of AD.

Effects of Dioxins, PCBs, and PBDEs on Immunology and Hematology in Adolescents

Dioxins and PCBs are environmental pollutants, proven to be immunotoxic. In the period 1987-1991 a cohort of mother-baby pairs was initiated to detect abnormalities in relation to dioxin levels in the mothers milk. At birth and at follow-up at 8-12 years, immunological and hematological effects were seen, prompting us to perform a new follow-up during adolescence. In addition, we assessed the immunological and hematological parameters in relation to current levels of PBDEs and PCBs. In the Netherlands, the pre- and postnatal exposure to dioxins have been studied prospectively since 1987. Venapuncture was performed to assess hematological (Hemoglobin, thrombocytes, thrombopoietin) and immunological (leukocytes, leukocyte differentiation) parameters and the current serum levels of dioxin, dioxinlike (dl)-PCBs and PBDEs. A decrease in the number of polymorphic neutrophils was found in adolescents with higher dl-PCBs in their serum (p = 0.021). No relation with total leukocytes, thrombocytes, hemoglobin, or thrombopoietin levels was seen. Similarly, we found no relation between prenatal, nor current dioxin levels and the hematological and the immunological parameters determined. The SigmaPBDEs were negatively associated with the number of lymphocytes (p = 0.01) and positively associated with the hemoglobin concentration (p = 0.003). These effects on the innate immunity by current levels of dl-PCBs and on the adaptive immunity by PBDEs are disconcerting, especially as the dl-PCB (0.04-7.8 WHOTEQ pg/g lipid, mean: 2.2 WHOTEQ pg/g lipid) and SigmaPBDE levels (mean 14.0 ng/g lipid, including one outlier with a sum of 73.6 ng/g lipid) were not high.

Seasonality of long term wheezing following respiratory syncytial virus lower respiratory tract infection

Background: It is well known that respiratory syncytial virus (RSV) lower respiratory tract infection (LRTI) is associated with subsequent wheezing episodes, but the precise natural course of wheezing following RSV LRTI is not known. This study aimed to determine the continuous development of wheezing following RSV LRTI in children up to the age of 3 years. Methods: A prospective cohort study was performed in 140 hospitalised infants with RSV LRTI. Continuous follow up data were obtained with a unique log in which parents noted daily respiratory symptoms. Results: A marked decrease in wheezing was seen during the first year of follow up. The burden of wheezing following RSV LRTI was observed during the winter season. Signs of airflow limitation during RSV LRTI were strongly associated with wheezing during the follow up period. Total and specific serum immunoglobulin E levels, patient eczema, and parental history of atopy were not associated with wheezing. Conclusions: Airway morbidity following RSV LRTI has a seasonal pattern, which suggests that viral upper respiratory tract infections are the predominant trigger for wheezing following RSV LRTI. There is a significant decrease in airway symptoms during the first 12 months after admission to hospital. Simple clinical variables, but not allergic risk factors, can predict the development of wheezing following RSV LRTI.