S. Van Daele

Pseudomonas aeruginosa in the home environment of newly infected cystic fibrosis patients

The source of acquisition of Pseudomonas aeruginosa in cystic fibrosis (CF) patients remains unknown. Patient-to-patient transmission has been well documented but the role of the environment as a source of initial infection is as yet unclear. In the present study, the origin of the first P. aeruginosa isolate in CF patients was investigated by comparing the P. aeruginosa genotype(s) from newly infected patients with genotypes of P. aeruginosa isolates from the home environment and from other patients from the same CF centre. A total of 50 newly infected patients were studied. P. aeruginosa could be cultured from 5.9% of the environmental samples, corresponding to 18 patients. For nine of these, the genotype of the environmental P. aeruginosa isolate was identical to the patients isolate. In total, 72% of the environmental P. aeruginosa isolates were encountered in the bathroom. Patient-to-patient transmission within the CF centre could not be ruled out for three patients. In summary, a low prevalence of Pseudomonas aeruginosa was found in the home environment of the newly infected cystic fibrosis patients. The bathroom should be targeted in any preventive cleaning procedures. An environmental source of the new infection could not be ruled out in nine patients.

Polymorphisms in the lectin pathway genes as a possible cause of early chronic Pseudomonas aeruginosa colonization in cystic fibrosis patients.

Genes of innate immunity may be involved in early onset of chronic Pa (Pseudomonas aeruginosa) colonization (cPaC) in cystic fibrosis (CF) patients. We studied 19 single nucleotide polymorphisms (SNPs) in 5 genes coding for proteins of the lectin complement pathway: MBL2 (Mannose binding lectin 2), MASP 1, 2, 3 (MBL-associated serine Protease) and FCN 1, 2 (Ficolin) gene in 96 CF patients. Association survival analysis using different genetic models was performed looking for an association between SNPs and age at onset of cPaC. CF patients who are MBL deficient are earlier chronic Pa colonized compared to MBL sufficient patients. Also patients with MBL2 genotype YO/YO, YO/XA, XA/XA, YA/YO and YA/XA are earlier chronic Pa colonized. CF patients heterozygous or homozygous for mutant alleles of two linked SNPs in the FCN1 gene (rs2989727 and rs1071583) are earlier colonized with Pa. Similarly, earlier onset of Pa colonization is seen in CF patients heterozygous for linked SNPs of FCN2 gene (rs7865453 and rs7851696) and MASP3 gene (rs7851696). Variants in MBL2, FCN1, FCN2 and MASP3 genes are significantly associated with earlier onset of chronic P. aeruginosa colonization.

Survey of Pseudomonas aeruginosa genotypes in colonised cystic fibrosis patients

The current authors aimed to examine whether cystic fibrosis (CF) patients in Belgium shared Pseudomonas aeruginosa genotypes and to compare the genotypes of isolates from the same patients during two consecutive years. A Belgian databank of the P. aeruginosa genotypes of all colonised CF patients was created. Sputum samples from a total of 276 P. aeruginosa colonised patients during 2003, and from a subgroup of 95 patients in 2004, were analysed. Patients were asked about any social contact between each other by questionnaire. All P. aeruginosa isolates exhibiting different colonial morphology on McConkey agar were first genotyped using arbitrarily primed PCR, whereafter single representatives of each randomly amplified polymorphic DNA-type were further genotyped by fluorescent amplified fragment length polymorphism analysis. In the 213 patients from whom P. aeruginosa could be cultured (resulting in 910 isolates), a total of 163 genotypes were found. The majority (75%) of patients harboured only one genotype. In most of the limited number of clusters, previous contacts between patients could be suspected. In 80% of the patients studied during both years, P. aeruginosa genotype remained unchanged. In conclusion, most colonised cystic fibrosis patients harbour only one Pseudomonas aeruginosa genotype, despite showing different colonial morphotypes. The number of clusters is limited, and most patients seem to retain the same genotypic strain during both years.

Inhaled steroids compared with disodium cromoglycate in preschool children with episodic viral wheeze

In school children with atopic asthma the beneficial effects of disodium cromoglycate (DSCG) and beclomethasone dipropionate (BDP) are well‐established. In preschool children, wheezing is quite common, and in the majority of cases the symptoms are episodic and reported to be associated with viral infections rather than atopy. We compared the efficacy of regular treatment with DSCG and BDP for prevention of wheezing in preschool children. We were interested to establish whether regular treatment with inhaled anti‐inflammatory drugs could lead to a decrease in bronchial responsiveness. In 15 patients (median age, 56 months; range, 43–66 months) bronchial responsiveness was assessed by measuring specific airway resistance (sRaw) during a histamine provocation test. The concentration of histamine eliciting a 100% increase in sRaw (PC100his) was determined. In a double‐blind crossover study, patients inhaled either DSCG 10 mg three times a day or BDP 100 μg three times a day for 2 months. After a wash‐out period, treatment was changed to BDP or DSCG, respectively. Daily peak flow measurements were carried out, and exacerbations were noted. PC100his was measured at the start and end of each treatment period.

Communication in healthcare: a narrative review of the literature and practical recommendations.

Effective and efficient communication is crucial in healthcare. Written communication remains the most prevalent form of communication between specialised and primary care. We aimed at reviewing the literature on the quality of written communication, the impact of communication inefficiencies and recommendations to improve written communication in healthcare.

Genetic variations in toll-like receptor pathway and lung function decline in Cystic fibrosis patients

The toll-like receptor (TLR) family maintains pulmonary homeostasis by pathogen recognition, clearance and regulation of inflammation. Genes affecting inflammation response play a key role in modifying Cystic fibrosis (CF) lung disease severity. We assessed the impact of single nucleotide polymorphisms (SNPs) of TLR genes (TLR1 to TLR10, CD14, lipopolyssacharide-binding protein (LBP)) on lung function in CF patients. Each SNP was tested for time-dependent effect on FEV1, using six genetic models. In addition, we investigated associations between SNP genotypes and extreme subject specific slopes of FEV1 decline. Variant alleles of polymorphisms of TLR2 rs1898830, rs5743708, and rs3804100 demonstrated a consistent association with lung disease severity (p = 0.008, p = 0.006 and p = 0.029 respectively). Patients homozygous for variant C allele of TLR5 polymorphism rs5744174 are more frequently associated with extreme fast FEV1 decline (OR: 20 (95% Confidence Interval:1.85-216.18)). Patients homozygous AA for TLR1 polymorphism rs5743551 are more frequently associated with faster decline of FEV1 compared to heterozygous genotype (OR:7.33 (95% CI:1.63-33.11). Our findings indicate that variations in TLR1, TLR2 and TLR5 genes may influence CF lung function decline. Further functional analysis is required to provide new insights into the pathogenesis of TLRs in CF lung disease severity.

Achromobacter xylosoxidans induced bronchiolitis obliterans in cystic fibrosis.

We report a 12‐year‐old boy with progressive bronchiolitis obliterans caused by Achromobacter xylosoxidans (Ax) colonization after liver transplantation, resulting in a steep decline in lung function. Pediatr Pulmonol. 2014; 49:414–416.

75 A single clone of Achromobacter xylosoxidans colonizes Belgian cystic fibrosis patients from different centres

Objective Several major infection problems with Achromobacter xylosoxidans were observed for CF patients in Belgium. We tried to assess the epidemiology. Methods We typed 50 strains from 24 CF patients – from Ghent University Hospital (UZG, n=17) and from the University of Antwerp Hospital (UZA, n=7), most of which (14 from Ghent and 5 from Antwerp) had stayed at the rehabilitation centre. CF-related strains had been collected over a period of 10 years. We also included 8 unrelated strains: 7 clinical strains from non-CF patients and the type strain. McRAPD (arbitrarily primed PCR in combination with melting curve analysis)(Deschaght et al. 2011. Res Microbiol 162: 386–392), nrdA gene sequencing (Spilker et al. 2013. J Cystic Fibrosis 12: 298–301) and MALDI-TOF typing (newly developed) were used for typing. Results Typing revealed that most isolates from CF patients were indistinguishable by any of the three approaches. Only 6 CF patients had invididual types of A. xylosoxidans . Non-CF strains, including the one isolated from a non-CF patient at the rehabilitation centre, belonged to separate genotypes. The major clone observed in this study had previously been recognized as a major cluster (10 patients) in the rehabilitation centre of De Haan and its distinctness from a previously established minor cluster in De Haan (4 patients, Van Daele et al. 2005. J Clin Microbiol 43: 2998–3002) was confirmed in this study. Conclusion These data indicate that most CF patients from different CF centres in Belgium are colonized by a single clone of genuine A. xylosoxidans , that is spreading since at least 10 years. We thank the MucoVereniging Belgium

156 Exercise performance in children with mild cystic fibrosis (CF): Are there arguments to enhance physical activity?

Objectives Physical activity is strongly recommended in children with CF to improve exercise capacity and quality of life. The aim of this study is to investigate exercise performance and oxygen consumption in children with CF and mild respiratory involvement. Methods Children with mild CF (FEV1>60%) who where referred for cardiopulmonary exercise testing (CPET) were enrolled. Maximal heart rate (HR), oxygen consumption (VO2max), respiratory exchange ratio (RER), VO2 at anaerobic threshold (AT) and HR at AT were analysed. Data were compared with a healthy control group. Results 20 CF patients (9 boys, 12.5±2.7 yrs, weight 47.1±11.2 kg, length 156.1±14.7cm) performed a CPET. FEV1 was 91.8±15.9%, not different from a normal population. They were compared with 60 healthy controls (30 boys, age 11.5±2.3 yrs, weight 43.6±12.4 kg, length 151.2±13.6cm). MaxHR was 180.7±13.7 bpm in CF and 185.2±12.7 in controls (P>0.05). RER at maximal exercise was 1.1±0.1 in CF versus 1±0.1(P Conclusion Children with mild CF have lower VO2max despite equal maximal load, test duration and HR. They reach AT at a lower HR and VO2, which highlights the impaired condition. We can conclude that it is important to stimulate physical activity in children with mild CF to improve VO2 during exercise.

WS19.7 Pseudomonas aeruginosa genotyping: Predicting transition to chronic colonization in cystic fibrosis patients

Objectives Chronic respiratory infection with Pseudomonas aeruginosa (Pa) is known to increase morbidity in cystic fibrosis (CF) patients. Following a first ever Pa isolation, patients may go through subsequent episodes of intermittent colonization, preceding chronic colonization by a variable time span, before chronic infection eventually is established. Currently, definitions of chronic colonization are based on the frequency of Pa isolation. This study evaluates whether genotyping of subsequent Pa isolates can be predictive towards persistence of Pa , and therefore towards transition from intermittent to chronic colonization. Methods Between January 2002 and December 2014 respiratory samples were prospectively collected and cultured from 80 CF patients with a first ever Pa isolation and all available isolates were compared using McRAPD genotyping (Deschaght et al.). Results Sixty-eight patients, 22 of which became chronically colonized – according to the European consensus criteria – during the study period, had at least one subsequent Pa isolate. Isolates were genotyped for a sample group of 25 patients. For 10 out of the 11 patients becoming chronically colonized during the study period. the first and second isolate were identical, as compared to for only 7 out of the 14 patients remaining non-chronically colonized (p Conclusion Our results indicate that the presence of a genotypically identical subsequent Pa isolate can predict impending chronic colonization. As such, genotyping and comparison of the subsequent Pa isolates could – for many patients – speed up the diagnosis of chronic colonization, compared to the currently used criteria.