Search

A hallmark of the newly published GLI (Global Lungs Initiative) spirometric reference values is their "all-age" (3-95yr) predictive power, accomplished by incorporating non-linear age dependencies into modelling parameters. This modelling strategy is especially promising for the age range of puberty; however, the performance of GLI-values for adolescents is currently unknown. We calculated GLI-based z-scores for children/adolescents without apparent respiratory diseases from two different German studies, LUNOKID (N = 1943, 4-19 years) and GINIplus (N = 1042, 15 years) and determined the goodness of fit for specific age groups. We defined fit sufficient if the absolute mean of z-scores was <0.5. For children (<10yr) the mean GLI-based z-scores for FEV1 and FVC reached a good fit with mean z-scores for FEV1 between -0.11 and 0.01 and mean z-scores for FVC between 0.01 and 0.16, but larger deviations were observed in adolescents, especially boys (mean z-score -0.58 for FEV1 and -0.57 for FVC in GINIplus). The fit for FEV1/FVC was sufficient. GLI reference values provided reasonable estimates for the individuals enrolled in our studies, which span the age range of lung growth and development. However, we found that GLI-predictions overestimated lung volumes, especially those for German adolescent boys, which may, left unrecognised, lead to erroneous diagnosis of lung disease. Caution should be taken when applying these reference values to epidemiologic studies.

The gold standard for assessing quality of forced expiratory manoeuvres is visual inspection by an expert. American Thoracic Society/European Respiratory Society numerical quality criteria (NQC) include back-extrapolated volume (BEV), repeatability and forced expiratory time (FET). Equipment currently available provides feedback tempting the investigator to use NQC as pass-fail criterion. To investigate whether using NQC instead of visual acceptability is a valid option, we analysed data from a multicentre national reference study in Germany of children aged 4-18 years. Spirometry was performed under field conditions. Receiver operating characteristic analysis was used to assess performance of BEV, repeatability, FET and a combination thereof in relation to visual acceptability. We included data from 3133 healthy Caucasians in the analyses; 72% delivered at least two visually acceptable manoeuvres. Of these, 59% would have been rejected based on combined NQC, mainly because the FET criterion was not feasible. Specificity of the NQC was generally low (BEV 10%, repeatability 30% and FET 50%). Receiver operating characteristic analysis showed that a combination of the three measures could reach at best a sensitivity of 90% and specificity of 56%. We conclude that visual control is mandatory and NQC may help obtain the best possible results, but a fixed cut-off for FET should be abandoned.

Background: Comparing children's lung function with reference values is important for diagnosing respiratory diseases. The values by Zapletal et al., commonly used nowadays, are not appropriate for the current stage of children's development. We have now developed new reference values and a lower limit of normal (LLN) for children in Germany, divided into small-range age and height categories., Material and Methods: We examined 4- to 18-year-old children in 3 German communities under field conditions. 1943 children were healthy and had a visually acceptable lung function which also fulfilled international quality criteria. We used the regression model LMS, which was introduced by Stanojevic and Quanjer in this context., Results: There were significant differences between the measured lung function and the predicted values according to Zapletal et al. The lung function did not only depend on the child's height, but also in a non-linear way on the age. The variation coefficient did not depend on age., Conclusions: To avoid diagnostic errors, the currently often used reference values according to Zapletal et al. should no longer be used. The non-linear dependence on age corresponds to the recently published results by Stanojevic and Quanjer., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: Tumor necrosis factor (TNF) is a central mediator of sepsis. The NcoI polymorphism within the TNF locus has been described as a prognostic marker for mortality in adult patients with sepsis., Objectives: The aim of our study was to investigate the genotype and allele distribution of 2 TNF gene polymorphisms in preterm infants <32 weeks of gestational age, who developed early-onset sepsis., Methods: A double-blinded retrospective cohort study was carried out on stored Guthrie blood spot cards with group A including 67 premature infants <32 weeks of gestational age with proven early-onset sepsis and group B including 102 healthy newborn infants (>32 + 0 weeks of gestation). The genotype andallele distribution of the study population were also compared to reference groups of healthy adult volunteers (n = 252 for TNF-beta NcoI and n = 233 for -308 TNF-alpha promoter). Polymorphisms of the TNF-alpha promoter -308 region and the NcoI site of the TNF-beta gene were assessed using PCR followed by melting curve analysis or NcoI digestion. The groups were compared by estimation of Hardy-Weinberg equilibrium., Results: The overall allele frequency and genotype distribution of the -308 TNF-alpha and NcoI polymorphism of the TNF-beta gene were comparable to the values found in the controls., Conclusion: The study results suggest that none of the analyzed TNF gene polymorphisms may serve as a prognostic marker for preterm infants at high risk of sepsis., (Copyright (c) 2006 S. Karger AG, Basel.)