C.K. van der Ent

Diagnostic value of serological tests against Pseudomonas aeruginosa in a large cystic fibrosis population

Background: Serological methods to monitor Pseudomonas aeruginosa colonisation in patients with cystic fibrosis (CF) are advocated but the diagnostic value of a commercially available P aeruginosa antibody test to detect early and chronic P aeruginosa colonisation in a non-research setting has not been assessed. Methods: Colonisation with P aeruginosa was estimated by regular culture of sputum or oropharyngeal swabs during three consecutive years in 220 patients with CF aged 0–65 years. Commercially available ELISA tests with three P aeruginosa antigens (elastase, exotoxin A, alkaline protease) were performed at the end of the study period. In a subgroup of 57 patients (aged 4–14 years) serological tests were performed annually. Results: Using culture as the reference standard, the ELISA tests using the advised cut off values had a sensitivity of 79% and a specificity of 89% for chronic colonisation. Receiver-operator characteristic curves were created to optimise cut off values. Applying these new cut off values resulted in a sensitivity of 96% and a specificity of 79%. All three individual serological tests discriminated well between the absence and presence of chronic P aeruginosa colonisation. The sensitivity of the individual antibody test was 87% for elastase, 79% for exotoxin A, and 76% for alkaline protease. First colonisation was preceded by positive serological results in only five of 13 patients (38%). Conclusion: In patients with CF, serological tests using specific antigens are sensitive for diagnosing chronic P aeruginosa colonisation. However, the failure of serological tests to detect early colonisation in young patients emphasises the need for continued reliance on cultures.

Spirometry in young children: should computer-animation programs be used during testing?

Currently, computer-animation programs are frequently used to instruct and stimulate young children in performing maximal expiratory flow/volume (MEFV) curves. The reproducibility and maximal performance of MEFV manoeuvres with and without the use of two computer-animation programs (the “candles” and the “balloon” programs) were evaluated. Eighty-eight children, aged 4–8 yrs, were randomly assigned to one of the two animation programs. All children performed two series of at least three technically acceptable curves, one series with the incentive and one without, in random order. With the use of computer-animation programs, a lower proportion of children were able to fulfil international criteria for forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) reproducibility. The use of incentives improved reproducibility and performance of peak expiratory flow (PEF). Performance of FVC decreased significantly in 6–8‐yr-old children using the animation programs. Training with a program for a short period of time before the formal lung-function test may be valuable. According to the results, however, the use of these programs during tests under the guidance of an experienced lung-function technician cannot be routinely recommended because of possible deteriorating effects on reproducibility and performance of forced expiratory manoeuvres.

Poor perception of dyspnoea in children with undiagnosed asthma

The aim of the present study was to establish the differences in dyspnoea perception between children with undiagnosed and diagnosed asthma. A cross-sectional community-based study was performed, which included a parental questionnaire on the childs respiratory health and testing of airway reversibility and bronchial hyperresponsiveness (BHR). “Diagnosed asthma” was defined by a physicians diagnosis of asthma. “Undiagnosed asthma” was defined by the presence of asthma symptoms combined with either airway reversibility or BHR without a physicians diagnosis of asthma. Only children with a positive BHR test were selected for further analysis. Perception of dyspnoea was assessed using the Borg scale and the visual analogue scale (VAS), plotted against the percentage fall in forced expiratory volume in one second and expressed as the slope of the regression line. Of the initial 1,758 participating children, 70 had undiagnosed asthma and 38 had diagnosed asthma. The Borg and VAS slopes in children with undiagnosed asthma were less steep than those of children with diagnosed asthma (Borg: 0.07 and 0.14, respectively; VAS: 0.06 and 0.11, respectively). Among children with bronchial hyperresponsiveness, those without a parents report of physicians diagnosis of asthma had a worse perception of dyspnoea than children with diagnosed asthma.

A bioassay using intestinal organoids to measure CFTR modulators in human plasma

Treatment efficacies of drugs depend on patient-specific pharmacokinetic and pharmacodynamic properties. Here, we developed an assay to measure functional levels of the CFTR potentiator VX-770 in human plasma and observed that VX-770 in plasma from different donors induced variable CFTR function in intestinal organoids. This assay can help to understand variability in treatment response to CFTR potentiators by functionally modeling individual pharmacokinetics.

Participation in Daily Life of Children with Asthma

Asthma can have a negative effect on psychological and social well-being in childhood. Sports participation, school attendance, and quality of life are important issues for children with asthma and their parents. However, a structural evaluation of these factors is not always incorporated in the routine medical approach of children with asthma. Moreover, goals in asthma treatment, such as minimal symptoms and normal activity levels, are achieved in a minority of children. This review describes determinants that are important for the well-being of children with asthma and their parents. Besides the control of symptoms, factors such as sports participation, socializing in peer groups, school attendance, and quality of life must be considered. These issues are relevant when evaluating the management of children and adolescents with asthma. A multidisciplinary evaluation by a pediatrician, school nurse, gym teacher, and psychologist might contribute to an important decrease in the impact of asthma on daily life.

Nutritional intervention in patients with Cystic Fibrosis: A systematic review

BACKGROUND To systematically assess the literature published after 1997 describing the effectiveness of nutritional interventions in Cystic Fibrosis patients. METHODS An online search in PUBMED, EMBASE and COCHRANE databases was conducted. Original studies with 4 patients or more, describing a nutritional intervention and giving at least weight as an outcome parameter were included. RESULTS The inclusion criteria were met by 17 articles, focusing on respectively behavioural interventions (n=6), oral supplementation (n=4) or enteral tube feeding (n=7). This latter intervention was universally successful to induce weight gain. One behavioural study and 2 oral supplementation studies also reported significant weight gain. CONCLUSION Enteral tube feeding is effective to improve nutritional status, while the described effects of behavioural intervention and oral supplementation are not consistent at present.

Dietary intake in children and adolescents with cystic fibrosis.

BACKGROUND & AIMS The recommendation for caloric intake in CF patients is to obtain intakes between 110 and 200% of the estimated average requirement (EAR) for age groups and gender, of which 35-40 energy% should be from fat. It is questionable whether the advice is met. METHODS 1726 Completed 3-day dietary food records of 234 CF patients (111 girls) and 2860 completed two non-consecutive 24-h dietary assessments of healthy controls (1411 girls) were studied. The dietary intake in CF patients was compared with that of healthy controls by using independent sample t tests. RESULTS Caloric intake in children with CF varied highly with age (88-127% EAR), which is below or in the lower range of the recommended 110-200% EAR. However the absolute caloric intake in CF children was significantly higher compared to controls at all ages. In addition, apart from boys aged 1-3 years, all CF children had a fat intake of 35 energy% or more. This fat intake was significantly higher than in controls, as was the consumption of saturated fat, the latter being well above 10% of the total energy intake. CONCLUSION Although CF patients generally do not meet the EAR recommendations, they had a significantly higher caloric intake than controls. Moreover fat intake in CF patients does generally meet recommendations, but this resulted in a considerable consumption of saturated fat; a reduction of the latter seems appropriate.

Comparing 6 and 10 Sec Exhalation Time in Exhaled Nitric Oxide Measurements in Children

Standard exhalation time for Fractional exhaled Nitric Oxide (FeNO) measurements is 10 sec but this is difficult for young children. Recommended exhalation time for children is 6 sec, but this was never substantiated in literature. We aimed to investigate the agreement between FeNO values measured with exhalation times of 6 and 10 sec and the preference of children for either method. The study population comprised children aged 5–17 years visiting the Pediatric Pulmonology outpatient clinic. FeNO values, measured during 6 (FeNO‐6) and 10 (FeNO‐10) sec (random order) using the single‐breath online (SBOL) technique, were compared. Preferences for exhalation times were related to FVC values. Ninety‐eight children (mean age 10.6 years) were included. Median FeNO‐6 (15.2 ppb) and FeNO‐10 (13.6 ppb) did not differ significantly (P = 0.259). Mean difference between FeNO‐6 and FeNO‐10 was −0.3 ppb, limits of agreement ranging from −5.8 ppb to +5.3 ppb. Sixty percent of children with a Forced Vital Capacity (FVC) less than 3 L preferred the FeNO‐6 method. We found good agreement between FeNO‐6 and FeNO‐10, so they can be used interchangeably. An exhalation time of 6 sec was preferred by the majority of subjects with a FVC below 3 L. Pediatr Pulmonol. 2009; 44:340–344.

Objective eliciting doses of peanut‐allergic adults and children can be combined for risk assessment purposes

To improve food labelling strategies, information regarding eliciting doses (EDs) and the effect of patient characteristics on these EDs is necessary.

Adherence to follow-up recommendations in asthma

A cross-sectional study showed that 130 out of 1758 (8%) primary school children without a previous asthma diagnosis had undiagnosed asthma. Thirty-eight per cent of their parents refused to visit a general practitioner for this disorder. Factors associated with the refusal were high maternal education, mild symptoms and absence of airway reversibility.