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Introduction In this cohort study spanning an 18-year period, we evaluated the prevalence and associated mortality rate of epidemic strains of pseudomonas aeruginosa (PsA), especially Australian Epidemic Strain Type 1 (AES1), in a pediatric cystic fibrosis center practicing cohort segregation and early PsA eradication. Methods Cohort segregation was introduced in January 2000. PsA clonal strain was determined by pulse-field-gel-electrophoresis (PFGE) at the time of routine collection of airway specimens. Children with PsA underwent eradication treatment with anti-pseudomonal antibiotics over 2-3 months. We analyzed changes in prevalence and mortality from 1999 to 2016. Results The prevalence of AES1 declined from 69 (20%) in 1999 to 16 (5.4%) in 2006, to 1 (0.4%) in 2016. The prevalence of PsA overall diminished less over the same period, from 128 (37%) patients in 1999 to 57 (23%) in 2016. New acquisition of AES1 became less common over time, with no new cases identified from 2011. Those who contracted AES1 had a greater risk of death than those who did not (Odds Ratio 4.9, 95%CI 2.5-9.6). Patients with other AES PsA types were uncommon (AES2 n = 5, AES5 n = 2, AES14 n = 3, AES19 n = 1). Conclusions Cohort segregation was associated with reduction in AES1 prevalence ascertained by PFGE surveillance for patients in a single large pediatric cystic fibrosis center. Other alterations in practice such as early eradication treatment may also have contributed to reduced PsA prevalence. These factors combined with the transition of chronically infected patients over time to adult centers has eliminated AES1 from our clinic, with an accompanying mortality decrease.

Osteopathia striata with cranial sclerosis (OSCS) is a rare X-linked skeletal dysplasia characterized by linear striations of the long bones, osteosclerosis of the cranium, and extraskeletal anomalies. We report a female infant with OSCS diagnosed radiographically with molecular confirmation in the first year of life. The patient presented at 5 months with severe obstructive sleep apnea, which had progressed rapidly after the neonatal period and which responded favorably to mandibular distraction osteogenesis. This procedure has not previously been reported in association with OSCS, which is a rare cause of Pierre Robin sequence with dysmorphic features.

A clonal strain of Pseudomonas aeruginosa (PA) was isolated in 1999 at the Royal Children's Hospital, Melbourne, Australia, after five unrelated children with cystic fibrosis (CF) died from severe lung disease aged5 yrs. Subsequently, more than half of the patients in the clinic with PA were found to harbour this strain, and segregation measures were instituted at the hospital to prevent further spread. The aim of this study was to assess CF parent and patient responses to the segregation measures to determine overall support. A questionnaire was sent out to the families of 291 CF children treated at the centre. A 65% response rate was obtained. The majority of parents (85%) and patientsor=12 yrs old (63%) were positive about the segregation measures instituted. A total of 11% of parents and 25% of patients were unsure, and 4% of parents and 12% of children gave negative responses. Those who were not happy listed reasons such as concerns about the emotional impact of not socialising with other CF children, inconclusive evidence about person-person spread of infection and feelings of alienation created in the clinic by the separation. In conclusion, the majority of responding cystic fibrosis patients and their families understand and are supportive of infection control measures instituted at the Royal Children's Hospital, Melbourne, Australia.

A 2-week-old female infant was transferred from a regional hospital for mechanical ventilation after developing severe respiratory distress. Stridor had been present since the age of 1 week and was complicated by coryzal illness. Mechanical ventilation was difficult with marked inspiratory and expiratory flow obstruction recorded by the ventilator. Echocardiogram showed a normal heart. Flexible bronchoscopy revealed mid-tracheal extrinsic compression (unchanged with positive end-expiratory pressure) and advancement of the endotracheal tube by 2 cm completely corrected the flow obstruction. Repeat echocardiogram showed a double aortic arch. This case report emphasizes the importance of clinical history, examination findings and interpretation of the ventilator waveforms in the differential diagnosis of a difficult-to-ventilate infant with bronchiolitis.

The detection of a clonal Pseudomonas aeruginosa strain in 21% of children attending a cystic fibrosis clinic during 1999, which may have led to a worse prognosis, prompted strict infection control measures, including cohort segregation. We determined whether these strategies interrupted cross-infection within the clinic. Patients from 1999 were observed and a cross-sectional study of the 2002 clinic was performed. By 2002, the epidemic strain prevalence had decreased from 21 to 14% (p = 0.03), whereas the proportion of patients with nonepidemic P. aeruginosa strains was unchanged. The age- and sex-adjusted relative risk for epidemic strains among sputum producers in 2002 compared with 1999 was 0.64 (95% confidence interval, 0.47, 0.87; p = 0.004). Increased mortality or transfer to another clinic did not explain this reduction. Although children with epidemic strains may have had increased mortality (adjusted odds ratio, 2.0; 95% confidence interval, 0.6-6.8), they did not demonstrate greater morbidity than those with other P. aeruginosa isolates. Successful infection control measures provided additional indirect evidence for person-to-person transmission of an epidemic strain within the clinic. Further studies are needed to resolve whether cohort segregation completely eliminates cross-infection and if acquisition of epidemic isolates is associated with worse outcomes.

Significant concern remains over the long-term side effects of inhaled steroids. This cross-sectional study evaluates the effect of high-dose inhaled fluticasone propionate (FP) on biochemical markers of bone metabolism and bone density in children with asthma. Children with chronic asthma using FP >/= 1,000 mcg daily for at least 6 months, and healthy controls, were entered in the study. No children had taken oral prednisolone within the previous month. Fasting morning serum was analyzed for bone formation markers, and spot urine for bone resorption markers. Dual-energy X-ray absorptiometry (DEXA) results were reviewed in a subgroup of patients. Forty-nine children with asthma and 32 controls were recruited. The mean FP dose was 771.2 +/- 253.35 mcg/m2/day. Unpaired t-test analysis revealed no significant difference in biochemical markers studied. In subjects with asthma; 13 of 37 (35.1%) had lumbar spine density more than one standard deviation below the mean (P = 0.001). This fell to 6/37 (16.2%) with bone age correction (NS). In conclusion, no significant reduction in bone metabolism or bone age-corrected bone mineral density was observed in children with asthma on prolonged high doses of inhaled FP.

BackgroundThe search for modifier genes to explain inconsistencies in cystic fibrosis (CF) genotype–phenotype relationships has yielded mixed results. In a previous cross-sectional study from our centre the clinical effect (as described by FEV1, BMI z-score, admitted days and NIH score) of single nucleotide polymorphisms (SNPs) of four cytokine genes (IL-8, TNF-α, IL-1β and IL-10) was examined in 158 children with CF. No association between cytokine genotype and any biological outcome measure was found. In this present study a cross-sectional and longitudinal examination of this relationship was undertaken to test the hypothesis that pro-inflammatory SNPs would affect longitudinal changes in CF lung disease.MethodsUsing the cohort examined in our earlier study we performed both longitudinal and cross-sectional data analyses examining the relationship between SNPs (TNF-α, IL-8, IL-10 and IL-1β) and clinical outcome measurements. In the first part of this current study, lung function data (annual decline of FEV1 percent predicted) was compared with the cytokine genotype over a 13year period. In the second part of this current study multiple regression was used to assess associations between clinical outcomes (best FEV1 percent predicted and BMI at the age of 10years) and alleles of cytokine genes, adjusting for gender, CF genotype and lung infection status.ResultsA total of 152 patients with CF were analysed in the longitudinal study and data from 130 patients at the age of 10years were analysed in the cross-sectional study. There was evidence for an association between pro-inflammatory SNPs of the IL-8, IL-10 and IL-1β genes and more severe lung disease. Multiple regression of the longitudinal data with a total of 10,956 lung function measurements showed an additional annual decline of the percentage predicted FEV1 of −1.15 (IL-8, p

Aim To evaluate changes in prevalence of an epidemic strain of Pseudomonas aeruginosa (AES-1, Australian epidemic strain, type 1) in a paediatric cystic fibrosis (CF) centre practising cohort segregation, to describe the patients' clinical characteristics at acquisition and observe mortality rates. Methods Cohort segregation was introduced in our paediatric CF clinic January 2000. The prevalence of AES-1 was analysed in 1999, 2002 and 2007. Age at acquisition, lung function, presence of bronchiectasis, hospitalisations, prior P. aeruginosa infection and mortality rates were collected. AES-1 infection was determined by pulse-field-gel-electrophoresis (PFGE) on airway specimen cultures taken three monthly. Results The prevalence of AES-1 declined from 21% in 1999 to 14% in 2002 (risk difference 7% (95% CI 1,13) p=0.0256) and to 6% in 2007 (risk difference 8% (95% CI 3,13) p=0.0018). New acquisitions after the introduction of cohort segregation were uncommon (10 by 2002 and another 7 by 2007) with a declining incidence of 3.3cases/year (1999 to 2002) compared to 1.4cases/year (2002 to 2007). Twenty-two of 32 (69%) deaths between 1999 and 2007 occurred in patients infected with AES-1. Conclusion Cohort segregation has been associated with reductions in the prevalence of AES-1 in our CF clinic. Mortality was higher in patients infected with AES-1 than other organisms.