Biofilm on Toothbrushes of Children with Cystic Fibrosis: A Potential Source of Lung Re-Infection after Antibiotic Treatment?

Frequent recurrent lung infections result in irreversible lung damage in children with cystic fibrosis (CF). This study aimed to determine if toothbrushes contain biofilms of pathogens, and act as potential reservoirs for lung re-infection following antibiotic treatment of acute exacerbations. Toothbrushes were collected from children with CF of lung infection before, during and after antibiotic treatment. Toothbrushes were rinsed with sterile saline and cultured. Bacterial isolates from toothbrushes were identified by 16s rRNA gene sequencing and compared with isolates from a sputum sample of the same patient. Scanning electron microscopy (SEM) was used to visually confirm the presence of bacterial biofilms and confocal laser scanning microscopy (CLSM) combined with Live/Dead stain to confirm bacterial viability. Large numbers of bacteria and biofilms were present on all toothbrushes. SEM confirmed the presence of biofilms and CLSM confirmed bacterial viability on all toothbrushes. Pathogens identified on toothbrushes from children before and during antibiotics treatment were in concordance with the species found in sputum samples. Pseudomonas aeruginosa and Staphylococcus aureus was able to be cultured from children's toothbrushes despite antibiotic treatment. Toothbrushes were shown to be contaminated with viable pathogens and biofilms before and during antibiotic treatment and could be a potential source of lung re-infections.

Safety of inhaled (Tobi®) and intravenous tobramycin in young children with cystic fibrosis.

BACKGROUND: Use of inhaled tobramycin therapy for treatment of Pseudomonas aeruginosa infections in young children with cystic fibrosis (CF) is increasing. Safety data for pre-school children are sparse. METHODS: The aim of this study was to assess the safety of tobramycin solution for inhalation (TOBI®-TSI) administered twice daily for 2 months/course concurrently to intravenous (IV) tobramycin during P. aeruginosa eradication therapy in children (0-5 years). Audiological assessment and estimation of glomerular filtration rate (GFR) was measured prior to any exposure and end of the study. RESULTS: Data were available from 142 patients who were either never exposed to aminoglycosides (n=39), exposed to IV aminoglycosides only (n=36) or exposed to IV+TSI (n=67). Median exposure to TSI was 113 days [59, 119]. Comparison of effects on audiometry results and GFR, showed no detectable difference between the groups. CONCLUSIONS: Use of TSI and IV tobramycin in pre-school children with CF was not associated with detectable renal toxicity or ototoxicity.

Detection of viral and bacterial respiratory pathogens in patients with cystic fibrosis.

The presence of viral respiratory infections is associated closely with exacerbations in patients with cystic fibrosis. Viral and bacterial multiplex PCRs were developed and applied to nasal swab samples from children with cystic fibrosis. This showed a large number of individuals with cystic fibrosis were infected with rhinoviruses, and more were infected with viral than bacterial pathogens. All individuals with parainfluenza 3 virus had clinical exacerbations of their cystic fibrosis, and although 3/4 of these children were co-infected with HRV. The findings do not suggest a significant association for any other virus or bacteria with exacerbation. There is clear evidence some viral infections are associated with cystic fibrosis that dual infection is more likely to produce symptoms, and mechanisms of viral-induced exacerbation should be elucidated.

Improved survival in cystic fibrosis patients diagnosed by newborn screening compared to a historical cohort from the same centre.

BACKGROUND: Newborn screening (NBS) for cystic fibrosis (CF) is associated with improved early nutritional outcomes and improved spirometry in children. The aim of this study was to determine whether early diagnosis and treatment of CF with NBS in New South Wales in 1981 led to better clinical outcomes and survival into early adulthood. METHODS: Retrospective observational study comprising two original cohorts born in the 3 years before ('non-screened cohort', n=57) and after ('screened'; n=60) the introduction of NBS. Patient records were assessed at transfer from paediatric to adult care by age 19 years and survival was documented to age 25 years. RESULTS: Non-screened patients (n=38) when compared with screened patients (n=41) had a higher rate and lower age of Pseudomonas aeruginosa acquisition at age 18 years (p ≤ 0.01). Height, weight and body mass index (BMI) z scores (all p<0.01) and forced expiratory volume in 1 s (FEV(1))% were better in the screened group (n=41) (difference: 16.7 ± 6.4%; p=0.01) compared to non-screened (n=38) subjects on transfer to adult care. Each 1% increase in FEV(1)% was associated with a 3% (95% CI 1% to 5%; p=0.001) decrease in risk of death and each 1.0 kg/m(2) increase in BMI contributed to a 44% (95% CI 31% to 55%; p<0.001) decrease in risk of death. This accumulated in a significant survival difference at age 25 years (25 vs 13 deaths or lung transplants; p=0.01). CONCLUSION: NBS for CF leads to better lung function, nutritional status and improved survival in screened patients in early adulthood.

Cystic fibrosis in Australia, 2009: results from a data registry.

OBJECTIVES: To describe the demographics, clinical features and outcomes among people with cystic fibrosis (CF) in Australia and to estimate incidence of the disease. DESIGN AND SETTING: Cross-sectional analysis using data from the Australian Cystic Fibrosis Data Registry for 2009. MAIN OUTCOME MEASURES: Numbers of diagnoses, pulmonary and anthropometric measurements, microbiological culture results, rates of hospitalisation and transplantation, and numbers of medical complications and deaths. RESULTS: In 2009, data were submitted on 2986 people (48% female). Median age was 17.6 years and 49% of people were aged 18 years or over. Seventy-eight people were newly diagnosed. Fourteen people died and 14 people underwent lung transplantation in the year. Lung function and nutrition were relatively normal among children but deteriorated (more rapidly) among adolescents. With increasing age, progressive respiratory disease was apparent, and the frequency of CF-related complications and use of health care resources increased. In all age groups, there was a wide range in severity of lung disease and nutritional status. CONCLUSIONS: CF remains a progressive respiratory disease and is associated with multisystem complications. The acceleration in disease severity in adolescence and early adulthood suggests that better treatment at these stages is required to further improve survival.

Post-natal corticosteroids are associated with reduced expiratory flows in children born very preterm.

AIM: Infants born very prematurely often received corticosteroids to minimise the risk of developing bronchopulmonary dysplasia (BPD) but their long term impact on lung function at school age is unclear. METHODS: A cross-sectional study of 105 children [mean gestation of 27 weeks] was undertaken. Lung function assessments were conducted at a mean age of 10 years according to standard criteria. Corticosteroid dose was obtained from the medical record. RESULTS: Spirometry in the BPD group was not significantly different to the non-BPD group, mean per-cent predicted (95% confidence interval) forced expiratory volume in 1 s (FEV1) 83% (79, 87) versus 86% (83, 90), FEF25%-75% 67% (60, 73) versus 75% (69, 81). Antenatal steroid treatment alone did not adversely affect airflow FEV1, 88% (84.92) versus 90% (82.97), and forced expiratory flow (FEF)25%-75%, 75% (69.81) versus 87% (70.104). Children who received post-natal corticosteroids had significantly lower flows than those who did not (FEV1 82% (78.85) vs. 88% (85.92), P = 0.006; FEF25%-75% 65% (59.71) vs. 78% (72.84), P = 0.003). Regression analysis revealed days on oxygen and days ventilated were statistically significant but weak predictors of airflow at 10 years of age. CONCLUSIONS: A diagnosis of BPD did not predict reduced spirometry in middle childhood. Children who received post-natal corticosteroids as preterm infants had reduced expiratory flows compared with those who did not. While post-natal corticosteroids may be a marker of severity of lung disease, the potential of post-natal corticosteroids to influence lung development requires further investigation.

Home IV Antibiotic Therapy and Exercise Capacity in Children with CF: A Case Series.

PURPOSE: This case series describes the effect of home intravenous (IV) antibiotic therapy on spirometry and exercise capacity in a group of children with cystic fibrosis (CF). METHODS: Outcomes from 10 children with CF who were prescribed a 14-day course of home IV antibiotics for a respiratory exacerbation are reported. All children performed spirometry and a modified shuttle test (MST) before and after 14-days of home IV therapy. RESULTS: After 14 days, FEV(1) increased by mean (± SE) 12 ± 4 % (p < 0.05) but mean MST did not improve compared to baseline. All children improved or maintained spirometry values with treatment, however, only 5 improved MST distance. CONCLUSION: After 14 days of home IV antibiotic therapy, a significant improvement in spirometry, but not exercise capacity, was seen in this small series of children with CF. The lack of improvement in exercise capacity for all children following home IV antibiotic therapy suggests factors other than spirometry determine exercise capacity. Identifying and investigating the factors that influence exercise capacity during home IV antibiotic therapy requires further investigation.

Segregation of children with CF diagnosed via newborn screening and acquisition of Pseudomonas aeruginosa.

BACKGROUND: Data from the Wisconsin newborn screening (NBS) study show that neonatally diagnosed infants are at risk of early Pseudomonas aeruginosa (PsA) acquisition. We have had NBS since 1981 and in 2003, introduced PsA-free 'segregation' from older patients for children < or =5. This study investigated the effect of simple 'segregation' on acquisition of respiratory pathogens. METHODS: Sputum culture results (n=2814) and details of antibiotic use before (1999-2002) and after (2004-2007) 'segregation' were collected. RESULTS: Each year each child provided an average of 4.6 samples for culture. There was a significant decrease (p< or =0.001 Chi(2)) in the acquisition of mucoid (from 5.9% of children to 1.0%) but not non-mucoid PsA (22.3% and 22.7%, respectively) after 'segregation'. There was no significant change in other respiratory pathogens. CONCLUSIONS: Young children with CF diagnosed via NBS can be protected from the acquisition of mucoid PsA by 'segregation' and the acquisition of non-mucoid PsA is likely to be from environmental sources outside the hospital.

Modifier gene study of meconium ileus in cystic fibrosis: statistical considerations and gene mapping results.

Cystic fibrosis (CF) is a monogenic disease due to mutations in the CFTR gene. Yet, variability in CF disease presentation is presumed to be affected by modifier genes, such as those recently demonstrated for the pulmonary aspect. Here, we conduct a modifier gene study for meconium ileus (MI), an intestinal obstruction that occurs in 16-20% of CF newborns, providing linkage and association results from large family and case-control samples. Linkage analysis of modifier traits is different than linkage analysis of primary traits on which a sample was ascertained. Here, we articulate a source of confounding unique to modifier gene studies and provide an example of how one might overcome the confounding in the context of linkage studies. Our linkage analysis provided evidence of a MI locus on chromosome 12p13.3, which was segregating in up to 80% of MI families with at least one affected offspring (HLOD = 2.9). Fine mapping of the 12p13.3 region in a large case-control sample of pancreatic insufficient Canadian CF patients with and without MI pointed to the involvement of ADIPOR2 in MI (p = 0.002). This marker was substantially out of Hardy-Weinberg equilibrium in the cases only, and provided evidence of a cohort effect. The association with rs9300298 in the ADIPOR2 gene at the 12p13.3 locus was replicated in an independent sample of CF families. A protective locus, using the phenotype of no-MI, mapped to 4q13.3 (HLOD = 3.19), with substantial heterogeneity. A candidate gene in the region, SLC4A4, provided preliminary evidence of association (p = 0.002), warranting further follow-up studies. Our linkage approach was used to direct our fine-mapping studies, which uncovered two potential modifier genes worthy of follow-up.

Newborn screening for cystic fibrosis offers an advantage over symptomatic diagnosis for the long term benefit of patients: the motion for.

Comprehensive newborn screening for cystic fibrosis has occurred for more than 25 years in some regions and the results of randomised controlled trials reporting the outcomes have been published. Testing protocols for CF have recently been reviewed and the sensitivity and specificity of these protocols are high. In spite of this, many remain sceptical in respect of the advantages conferred by newborn screening for CF. Every study of newborn screening has shown that diagnosis occurs at a significantly younger age. While this alone is sufficient to justify newborn screening, the clinical course of those diagnosed via newborn screening indicates that many additional advantages accrue. These include a decreased morbidity and mortality in early life, facilitation of better growth and prevention of vitamin deficiency in early infancy, as well as some indication of an advantage in terms of pulmonary status later in life. This review summarises the arguments in favour of newborn screening for CF.

Reduced exercise capacity in children born very preterm.

OBJECTIVE: In the past 20 years, there has been an increase in survivors of very preterm birth, but little is known regarding their long-term respiratory and fitness outcomes. We aimed to assess the 10-year lung function and fitness outcomes for children who were born weighing <1000 g and before 32 weeks' gestation in 1992-1994. METHODS: A cross-sectional study was conducted of 126 children (mean age: 10 years) who were born at a mean gestation of 27 weeks and 34 term-born control subjects. Extensive lung function (spirometry, lung volumes, and gas exchange) and fitness (6-minute walk and 20-m shuttle run tests) assessments were conducted at a single visit according to previously validated techniques. RESULTS: The preterm group had significantly lower values for all measured spirometric parameters compared with the control group. In contrast to airflow, the preterm group had significantly higher percentage predicted values in all standard lung-volume parameters and transfer factor than the control group. The exercise capacity of the preterm group was approximately half that of the control group. There was no significant difference in the distance walked in the 6-minute walk test. CONCLUSIONS: In the largest cohort of school-aged children (born very preterm in the 1990s) to undergo extensive lung function and fitness assessments, we demonstrated significant impairment in exercise capacity despite evidence of only mild small-airway obstruction and gas trapping. Additional studies are required to evaluate the cause of this exercise limitation and whether it can be improved with a training program.

Inhaled mannitol improves lung function in cystic fibrosis.

BACKGROUND: The airways in patients with cystic fibrosis (CF) are characterized by the accumulation of tenacious, dehydrated mucus that is a precursor for chronic infection, inflammation, and tissue destruction. The clearance of mucus is an integral component of daily therapy. Inhaled mannitol is an osmotic agent that increases the water content of the airway surface liquid, and improves the clearance of mucus with the potential to improve lung function and respiratory health. To this end, this study examined the efficacy and safety of therapy with inhaled mannitol over a 2-week period. METHODS: This was a randomized, double-blind, placebo-controlled, crossover study. Thirty-nine subjects with mild-to-moderate CF lung disease inhaled 420 mg of mannitol or placebo twice daily for 2 weeks. Following a 2-week washout period, subjects were entered in the reciprocal treatment arm. Lung function, respiratory symptoms, quality of life, and safety were assessed. RESULTS: Mannitol treatment increased FEV(1) from baseline by a mean of 7.0% (95% confidence interval [CI], 3.3 to 10.7) compared to placebo 0.3% (95% CI, - 3.4 to 4.0; p < 0.001). The absolute improvement with mannitol therapy was 121 mL (95% CI, 56.3 to 185.7), which was significantly more than that with placebo (0 mL; 95% CI, - 64.7 to 64.7). The forced expiratory flow in the middle half of the FVC increased by 15.5% (95% CI, - 6.5 to 24.6) compared to that with placebo (increase, 0.7%; 95% CI, - 8.3 to 9.7; p < 0.02). The safety profile of mannitol was adequate, and no serious adverse events related to treatment were observed. CONCLUSIONS: Inhaled mannitol treatment over a period of 2 weeks significantly improved lung function in patients with CF. Mannitol therapy was safe and well tolerated. TRIAL REGISTRATION: (ClinicalTrials.gov) Identifier: NCT00455130.

Lentivirus vector-mediated gene transfer to the developing bronchiolar airway epithelium in the fetal lamb.

BACKGROUND: Development of effective and durable gene therapy for treatment of the respiratory manifestations of cystic fibrosis remains a formidable challenge. Obstacles include difficulty in achieving efficient gene transfer to mature airway epithelium and the need to stably transduce self-renewing epithelial progenitor cells in order to avoid loss of transgene expression through epithelial turnover. Targeting the developing airway epithelium during fetal life offers the prospect of circumventing these challenges. METHODS: In the current study we investigated vesicular stomatitis virus glycoprotein (VSVg)-pseudotyped HIV-1-derived lentivirus vector-mediated gene transfer to the airway epithelium of mid-gestation fetal lambs, both in vitro and in vivo. In the in vitro studies epithelial sheet explants and lung organ culture were used to examine transduction of the proximal and more distal airway epithelium, respectively. For the in vivo studies, vector was delivered directly into the proximal airway. RESULTS: We found that even during the early pseudoglandular and canalicular phases of lung development, occurring through mid-gestation, the proximal bronchial airway epithelium was relatively mature and highly resistant to lentivirus-mediated transduction. In contrast, the more distal bronchiolar airway epithelium was relatively permissive for transduction although the absolute levels achieved remained low. CONCLUSION: This result is promising as the bronchiolar airway epithelium is a major site of pathology in the cystic fibrosis airway, and much higher levels of transduction are likely to be achieved by developing strategies that increase the amount of vector reaching the more distal airway after intratracheal delivery.

Pancreatic phenotype in infants with cystic fibrosis identified by mutation screening.

OBJECTIVE: To determine the pancreatic phenotype of infants with cystic fibrosis (CF) diagnosed in the first week of life by a combined immunoreactive trypsin/mutation screening program. DESIGN: A prospective evaluation of pancreatic function in infants with CF at the time of neonatal diagnosis and up to the age of 12. SETTING: Two different centres (Verona, Italy and Westmead, Australia) to enable comparison of results between two regions where <60% or > or =90% of patients, respectively, have at least one single DeltaF508 a mutation. PATIENTS: 315 children with CF including 149 at Verona and 166 at Westmead. INTERVENTIONS: Fat balance studies over 3-5 days and pancreatic stimulation tests with main outcome measures being faecal fat or pancreatic colipase secretion. PATIENTS with malabsorption are pancreatic insufficient (PI) or with normal absorption and pancreatic sufficient (PS). RESULTS: 34 infants (23%) at Verona and 46 (28%) at Westmead were PS at diagnosis. 15% of those with two class I, II or III "severe" mutations and 26/28 (93%) of those with class IV or V mutations were PS at this early age. Of the 80 infants with PS, 20 became PI before the age of 12. All 20 had two severe mutations. CONCLUSION: Neonatal mutational screening programs for CF are less likely to detect PS patients with non-DeltaF508 mutations. Of PS patients who are detected, those with two severe class I, II or III mutations are at particularly high risk of becoming PI during early childhood.

Modified shuttle test performance in hospitalized children and adolescents with cystic fibrosis.

BACKGROUND: The Modified Shuttle Test (MST) is a valid and sensitive measure of exercise capacity in adult CF patients. Recently, its validity in children has been demonstrated. The aim of this study was to demonstrate the utility of the MST as a measure of responsiveness to hospitalisation for i.v. antibiotic and supportive therapy in children and adolescents with CF. METHODS: 28 children and adolescents (40 admissions) performed a MST and lung function within 48 h of admission and discharge to hospital for administration of intravenous antibiotics. Mean age was 12.7 years and antibiotic therapy length was 14.7 days. RESULTS: Upon admission, the mean (S.D.) FEV(1) was 63 (19)% predicted, FVC was 80 (18)% predicted, FEF(25-75) 43 (29)% predicted and MST distance 718 (232) m. FEV(1) increased by 15% (p

The influence of newborn screening for cystic fibrosis on pulmonary outcomes in new South Wales.

OBJECTIVES: To determine whether early treatment of cystic fibrosis made possible by diagnosis after newborn screening results in improved pulmonary outcomes in adolescence. STUDY DESIGN: Both screening (SG) and non-screening groups (NSG) comprised a cohort of children from Australia previously studied at 1, 5, and 10 years of age. The groups were compared on measures of clinical status obtained during their comprehensive annual review conducted at or near the 15th birthday of the subjects. RESULTS: Data were collected on 48 of 57 original subjects in the NSG (7 had died; 2 were lost to follow-up) and 52 of 60 original subjects in the SG (4 had died; 2 transferred out of the country; 2 were lost to follow-up). Those dying in the SG were significantly older (by 48 months, P < .05) than those in the NSG. No statistically significant differences were found between the groups in nutritional status. However, subjects in the SG displayed statistically better total Shwachman-Kulczycki scores (7.0, P

Prevalence of allergic bronchopulmonary aspergillosis in cystic fibrosis in an area with a high frequency of atopy.

BACKGROUND: Lower airway colonisation with Aspergillus fumigatus and the complicating hypersensitivity reaction allergic bronchopulmonary aspergillosis (ABPA) is well recognised in patients with cystic fibrosis (CF). There is a wide range in reported prevalence of ABPA in CF. Differences in predisposing factors such as atopy and climatic humidity, but also differences in reporting may in part explain this observation. In the Australian population there is a high frequency of atopy and the climate is relatively humid. PATIENTS AND METHODS: Children and adolescents with CF (n = 277) from the CF Clinic, Children's Hospital at Westmead, Sydney, Australia were included in a retrospectively conducted study of Aspergillus colonisation and ABPA (1998-2003). RESULTS: The prevalence of Aspergillus colonised patients increased significantly from 7.4% in 1998 to 18.8% in 2002. No seasonal variation in initial positive Aspergillus culture or in humidity was observed. A total of 13 patients (4.7%) were diagnosed with ABPA over the study period, with a significant increase in prevalence from 0.3% in 1998 to 4.0% in 2002. In addition, the criteria used for reporting ABPA in the study population were in agreement with the recently published diagnostic criteria for ABPA in CF. CONCLUSIONS: In spite of a high frequency of atopy and a relatively humid climate in the Sydney area, Aspergillus colonisation and ABPA in CF patients was not disproportionate. Moreover, criteria for reporting of ABPA in this setting was not different from that in the Northern Hemisphere.