Nina Lenherr

Changes in breathing pattern upon 100% oxygen in children at early school age

Nitrogen multiple-breath washout (N2MBW) is an increasingly used tidal breathing test in young children to assess ventilation inhomogeneity. However, the test requires 100% oxygen to perform. We aimed to examine the potential influence of pure oxygen on breathing pattern in school-aged children. We performed tidal breathing measurements under room air followed by N2MBW in 16 former preterm children and 24 healthy controls. We compared tidal volume (VT), coefficient of variation of VT (CVVT), respiratory rate (RR), and minute ventilation (VE) between tidal breathing and N2MBW, and between the start and end of tidal breathing. Mean (range) age was 6.8 (5.9, 9.0) years. VT, RR and VE showed no significant change upon oxygen-exposure, while CVVT significantly decreased by 5% (95% CI: 1.2, 9.0; p=0.012). However CVVT was also the only parameter which significantly decreased during tidal breathing. Overall, pure oxygen has no systematic effect on breathing pattern in young school-aged children. N2MBW can reliably be used as tracer gas in this age group.

Leaks during multiple-breath washout: characterisation and influence on outcomes

Nitrogen multiple-breath washout (N2MBW) is increasingly used in patients with cystic fibrosis. The current European Respiratory Society/American Thoracic Society consensus statement for MBW recommends the rejection of measurements with leaks. However, it is unclear whether this is necessary for all types of leaks. Here, our aim was to 1) model and 2) apply air leaks, and 3) to assess their influence on the primary MBW outcomes of lung clearance index and functional residual capacity. We investigated the influence of air leaks at various locations (pre-, intra- and post-capillary), sizes, durations and stages of the washout. Modelled leaks were applied to existing N2MBW data from 10 children by modifying breath tables. In addition, leaks were applied to the equipment during N2MBW measurements performed by one healthy adolescent. All modelled and applied leaks resulted in statistically significant but heterogeneous effects on lung clearance index and functional residual capacity. In all types of continuous inspiratory leaks exceeding a certain size, the end of the washout was not reached. For practical application, we illustrated six different “red flags”, i.e. signs that enable easy identification of leaks during measurements. Air leaks during measurement significantly influence N2MBW outcomes. The influence of leaks on MBW outcomes is dependent on the location, relation to breath cycle, duration, stage of washout and size of the leak. We identified a range of signs to help distinguish leaks from physiological noise. The influence of leaks on nitrogen MBW outcomes is complex, dynamic and dependent on the size, duration, location and position of leaks during the washout and breathing cycle http://ow.ly/PbHV30hB91H

Aerococcus urinae: a possible reason for malodorous urine in otherwise healthy children

Recently, Aerococcus urinae, primarily recognized as a common pathogen in elderly women, has been reported to cause an extremely unpleasant odour of the urine in paediatric patients similar to trimethylaminuria (fish odour syndrome). Herein, we present a case of A. urinae urinary tract colonization in a 12-year-old otherwise healthy boy, who finally refused micturition outside from his home environment as a result of the unpleasant odour. Within the last year, three cases (including our own) of A. urinae colonization causing foul-smelling urine in healthy children have been published, suggesting that this condition might be as frequent as trimethylaminuria. In case of polymicrobial growth in a urine specimen, A. urinae as the leading pathogen will usually be missed by routine bacteriological investigation. Novel bacteriological techniques such as MALDI-TOF MS provide a rapid tool to recognize this pathogen in urine. Conclusion: As treatment of A. urinae infection is simple, we recommend that in healthy children with malodorous urine, this pathogen is excluded before the initiation of costly metabolic investigations.

Last Word on Viewpoint: Using the same cut-off for sulfur hexafluoride and nitrogen multiple-breath washout may not be appropriate

to the editor: We agree with all important points of the four commentaries (see Ref. [6][1]): a ) Both SF6- and N2-multiple-breath washout (MBW) seem to be useful in detecting ventilation inhomogeneity in patients with cystic fibrosis (CF) and primary ciliary dyskinesia (PCD). b ) There are

Neuroborreliosis-Associated Cerebral Vasculitis: An Uncommon Manifestation of Lyme Disease in a 9-Year-Old Boy.

Creative Commons CC-BY-NC: This article is distributed under the terms of the Creative Commons AttributionNonCommercial 3.0 License (http://www.creativecommons.org/licenses/by-nc/3.0/) which permits non-commercial use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access page (https://us.sagepub.com/en-us/nam/open-access-at-sage). Brief Report

Ivacaftor in a young boy with the rare gating mutation S549R - use of lung clearance index to track progress: a case report

BackgroundIvacaftor acts as a potentiator of the cystic fibrosis transmembrane conductance regulator (CFTR) and increases the transepithelial chloride transport of CFTR in 9 of 10 known gating mutations causing cystic fibrosis. S549R is a rare gating mutation considered to be less sensitive to potentiators than all other gating mutations.Case presentationWe report our first experience with ivacaftor in an 8-year-old boy with the rare S549R gating mutation. Besides subjective clinical improvements, the sweat chloride level and the lung clearance index decreased impressively within a few weeks of treatment while forced expiratory volume in the first second values remained in normal range.ConclusionWe emphasize the value of measuring small airway function by lung clearance index as an outcome measure for new interventions targeting the correction of the CFTR defect at an age before traditional lung function parameters start to deteriorate.

Ivacaftor – le premier médicament pour le traitement causal de la mucoviscidose

La mucoviscidose est une maladie hereditaire autosomale-recessive touchant quelque 70 000 personnes dans le monde entier. Cette maladie resulte de l’absence ou d’une dysfonction du canal du chlore dans les cellules epitheliales.