PubMed Health⌕ Search

Biomedical subjects

Colin F Robertson

Publications and source records attributed to Colin F Robertson.

At least 19 recordsLinked to original sources
PubMed2006

Short-course montelukast for intermittent asthma in children: a randomized controlled trial.

RATIONALE: In children, intermittent asthma is the most common pattern and is responsible for the majority of exacerbations. Montelukast has a rapid onset of action and may be effective if used intermittently. OBJECTIVES: To determine whether a short course of montelukast in children with intermittent asthma would modify the severity of an asthma episode. METHODS: Children, aged 2-14 years with intermittent asthma participated in this multicenter, randomized, double-blind, placebo-controlled clinical trial over a 12-month period. Treatment with montelukast or placebo was initiated by parents at the onset of each upper respiratory tract infection or asthma symptoms and continued for a minimum of 7 days or until symptoms had resolved for 48 hours. MEASUREMENTS AND MAIN RESULTS: A total of 220 children were randomized, 107 to montelukast and 113 to placebo. There were 681 treated episodes (345 montelukast, 336 placebo) provided by 202 patients. The montelukast group had 163 unscheduled health care resource utilizations for asthma compared with 228 in the placebo group (odds ratio, 0.65; 95% confidence interval, 0.47-0.89). There was a nonsignificant reduction in specialist attendances and hospitalizations, duration of episode, and beta-agonist and prednisolone use. Symptoms were reduced by 14% and nights awakened by 8.6% (p = 0.043), and days off from school or childcare by 37% and parent time off from work by 33% (p < 0.0001 for both). CONCLUSIONS: A short course of montelukast, introduced at the first signs of an asthma episode, results in a modest reduction in acute health care resource utilization, symptoms, time off from school, and parental time off from work in children with intermittent asthma.

Absenteeism↗
PubMed2006

Polyflex stenting of tracheomalacia after surgery for congenital tracheal stenosis.

Polyflex self-expanding stents (Rüsch, Germany) were used in three young children who had presented with life-threatening long-segment tracheal stenosis with bronchial stenosis in two cases. Two children had slide tracheoplasties and subsequently aortic homografts and another tracheal resection and autotracheoplasty. However, in all cases persistent lower tracheal malacia necessitated stenting. Complications of granuloma, stent migration or dislodgement occurred in all cases. A fatal tracheo-aortic fistula occurred in one child. Granuloma in one was treated successfully with steroids. One child survives.

Aorta, Thoracic↗
PubMed2006

Cough in children: definitions and clinical evaluation.

The aetiology and management approach for cough in children differs greatly to that in adults, so the empirical approach commonly used in adults is unsuitable for children. Clinical evaluation of cough in children should include an assessment of environmental factors, particularly tobacco smoke, parental concerns and expectations. Most children with acute cough are likely to have an uncomplicated viral acute respiratory tract infection, but the possibility of a more serious problem, especially aspiration of foreign material, should always be considered. Isolated chronic cough in children is rarely asthma, and the term "cough variant asthma" should not be used. Over-the-counter and prescription medications are ineffective for the symptomatic relief of acute cough. Treatment for chronic cough should be based on aetiology. Because of the favourable natural history of cough, a "positive" response in medication trials should not be assumed to be due to the medication. Children should be reassessed within the expected timeframe of response to therapy.

Acute Disease↗
PubMed2006

Clinical scoring systems in cystic fibrosis.

The first cystic fibrosis (CF) scoring system was published in 1958. Since then, many other scoring systems were developed. Clinical parameters, details about statistical evaluations, and recent strategic uses of scores were identified. Several similar scores aiming to assess chronic illness severity (Shwachman-Kulczycki score and a modification, Cooperman, Berneze-score and the NIH score) have not been evaluated and are out of date, given the changing natural history of CF. Of the current scoring systems, the modified Shwachman score by Doershuk is perhaps most reliable for describing follow-up studies. Scores designed for acute changes and short-term evaluation were also developed. The modified Huang score may be useful in the prognostic evaluation of patients with end-stage disease. It could also be used for discrimination of adult patients with differing disease severity and for longitudinal evaluation. Scores assessing pulmonary exacerbations could help provide consensus among clinicians regarding the need for intervention. Most of these scores require further evaluation. Although scores could provide an objective measure of disease severity, progression, need for and response to interventions, including value in selecting patients for lung transplantation and as an outcome measure for research studies, no scoring system can fulfill all these objectives. Nevertheless, there is a need for the development of a modern day longitudinal score that is sensitive, valid and reproducible, to reflect the milder disease status of patients.

Child↗
PubMed2005

Robust estimation of experimentwise P values applied to a genome scan of multiple asthma traits identifies a new region of significant linkage on chromosome 20q13.

Over 30 genomic regions show linkage to asthma traits. Six asthma genes have been cloned, but the putative loci in many linked regions have not been identified. To search for asthma susceptibility loci, we performed genomewide univariate linkage analyses of seven asthma traits, using 202 Australian families ascertained through a twin proband. House-dust mite sensitivity (Dpter) exceeded the empirical threshold for significant linkage at 102 cM on chromosome 20q13, near marker D20S173 (empirical pointwise P = .00001 and genomewide P = .005, both uncorrected for multiple-trait testing). Atopy, bronchial hyperresponsiveness (BHR), and forced expiratory volume in 1 s (FEV1) were also linked to this region. In addition, 16 regions were linked to at least one trait at the suggestive level, including 12q24, which has consistently shown linkage to asthma traits in other studies. Some regions were expected to be false-positives arising from multiple-trait testing. To address this, we developed a new approach to estimate genomewide significance that accounts for multiple-trait testing and for correlation between traits and that does not require a Bonferroni correction. With this approach, Dpter remained significantly linked to 20q13 (empirical genomewide P = .042), and airway obstruction remained linked to 12q24 at the suggestive level. Finally, we extended this method to show that the linkage of Dpter, atopy, BHR, FEV1, asthma, and airway obstruction to chromosome 20q13 is unlikely to be due to chance and may result from a quantitative trait locus in this region that affects several of these traits.

Adult↗
PubMed2005

Extending the limits of extracorporeal membrane oxygenation: lung rest for a child with non-specific interstitial pneumonia.

OBJECTIVE: Veno-venous extracorporeal membrane oxygenation (ECMO) is an established therapy for the treatment of respiratory failure. Traditionally ECMO has been used to support patients with an acute, reversible disease process, with a predictable outcome. We report the successful use of veno-venous ECMO for an unusual indication. PATIENT: A 10-year old girl was admitted to intensive care with severe, hypoxic respiratory failure on the background of a 2-month history of worsening respiratory symptoms. She required high levels of conventional positive pressure ventilation, and high frequency oscillation. Lung biopsy confirmed a non-specific interstitial pneumonia, and the patient was commenced on immune suppressive therapy. Her clinical course was further complicated by pulmonary haemorrhage and severe air leak. INTERVENTIONS: On day 20 after admission the patient was placed on veno-venous ECMO for lung rest while awaiting a response to continued medical treatment. She required ECMO for 20 days, during which time sedation was reduced, and she was able to interact with those around her. The patient's ventilatory requirements after decannulation were minimal, and she subsequently made a steady clinical recovery. CONCLUSIONS: ECMO was safely and successfully used to provide a period of lung rest and time for medical therapy to take effect in a child with an unusual indication for support: a rare disease with an uncertain outcome on the background of prolonged mechanical ventilation.

Child↗
PubMed2005

Intussusceptions arising from two different sites in a child with cystic fibrosis.

Abdominal pain is common in individuals with cystic fibrosis (CF). We report on a 17-year old boy with CF and two recognized intussusceptions: the first colonic intussusception was presumed due to distal intestinal obstruction syndrome, and the second enteric one due to polypoid lesions containing heterotopic gastric mucosa. The presentation, pathology, management, and a literature review of intussusception in CF are discussed.

Adolescent↗
PubMed2005

Lower airway inflammation in infants with cystic fibrosis detected by newborn screening.

Controversy exists over whether the lower airway inflammation that characterizes cystic fibrosis (CF) is initiated primarily by the genetic defect. To determine if inflammation precedes infection, we examined bronchoalveolar lavage (BAL) fluid cytology, cytokines (interleukin (IL)-1beta, IL-4, IL-5, IL-6, IL-8, IL-10, and tumor necrosis factor-alpha), and free neutrophil elastase activity from 70 CF (aged 1.5-71 months) children detected by newborn screening and 19 (aged 2.0-48 months) controls with chronic stridor. CF subjects were selected and categorized as pristine (13 aged </= 6 months, lacking prior respiratory symptoms and exposure to antibiotics, and without respiratory pathogens on BAL), infected (42 with viruses or >/= 10(5) colony-forming units/ml of pathogenic bacteria in BAL), and uninfected (15 aged > 6 months, asymptomatic, not taking antibiotics at bronchoscopy, and free of pathogens in their BAL). To further resolve if inflammation develops without infection, inflammatory mediators in paired annual BAL samples from 38 CF subjects were measured, and results were grouped according to whether BAL showed persistence (n = 6), acquisition (n = 8), clearance (n = 13), or absence (n = 11) of infection. While pristine, uninfected, and control subjects had similar BAL profiles, infected patients showed elevated inflammatory indices, including increased IL-10 (P < 0.001). Pristine subjects had the fewest signs of inflammation. Analysis of BAL pairs found differences between the four infection groups for changes in neutrophil percentages, IL-8 (P < 0.001), and free neutrophil elastase (P = 0.009). Infection was associated with elevated inflammatory mediators in BAL fluid. In contrast, minimal or reduced signs of inflammation accompanied absence of eradication of infection from BAL fluid. We conclude that in CF, infection initiates and sustains airway inflammation.

Bronchoalveolar Lavage Fluid↗
PubMed2005

Impact of disease severity on quality of life in adults with asthma.

Health-related quality of life is increasingly used as an outcome measure in asthma. The aim of this study was to define the relationship between asthma symptoms, lung function and health related quality of life in a community based sample of people with asthma ranging from no recent asthma to severe persistent asthma. We recruited subjects at the age of 42 years from a well-described community cohort, the Melbourne Epidemiological Study of Childhood Asthma, to define this association. 161 subjects completed a respiratory symptom survey, the Asthma Quality of Life Questionnaire and had lung function testing. According to the previous surveys and when applicable in agreement with GINA, subjects were classified into 4 groups: no recent asthma, sporadic asthma, intermittent asthma and persistent asthma, with the persistent asthma group further categorised by wheezing frequency and lung function. 55 had no recent asthma, 31 had sporadic asthma, 39 had intermittent asthma and 36 had persistent asthma. There was clear evidence of lower total scores with increased asthma severity, with median scores of 6.8 for the sporadic asthma group, 6.4 for the intermittent and 5.5 for the persistent asthma group compared to 6.9 in those with no recent asthma. All domain scores within the intermittent and persistent asthma groups were lower than scores for the no recent asthma group (p < 0.01). Those with persistent asthma and low FEV1% had the lowest quality of life scores (4.6). Analysis of this population cohort highlights that health related quality of life in patients with asthma strongly depends on symptom frequency and lung function and underlines the necessity of adequate treatment.

Adult↗
PubMed2004

Asthma prevalence in Melbourne schoolchildren: have we reached the peak?

OBJECTIVE: To determine the change in prevalence of asthma, eczema and allergic rhinitis in Australian schoolchildren between 1993 and 2002. DESIGN: Questionnaire based survey, using the protocol of the International Study of Asthma and Allergy in Childhood. SETTING: Metropolitan Melbourne primary schools within a 20 km radius of the GPO in 1993 and 2002. SUBJECTS: All children in school years 1 and 2 (ages 6 and 7) attending a random sample of 84 schools in 1993 and 63 schools in 2002. MAIN OUTCOME MEASURES: Parent-reported symptoms of atopic disease; treatment for asthma; country of birth. RESULTS: There was a 26% reduction in the 12-month period prevalence of reported wheeze, from 27.2% in 1993 to 20.0% in 2002. The magnitude of reduction was similar for boys (27%) and girls (25%). The 12-month period prevalence of reported eczema increased from 11.1% in 1993 to 17.2% in 2002, and rhinitis increased from 9.7% to 12.7%. There were reductions in the proportion of children attending an emergency department for asthma in the previous year (3.6% to 2.3%), the proportion admitted to hospital (1.7% to 1.1%) and the proportion taking asthma medication (18.5% to 13.4%). Of those who reported frequent wheeze, there was an increase in the proportion taking regular inhaled steroids (34.5% to 40.9%). CONCLUSION: There has been a significant reduction in the prevalence of reported asthma in Melbourne schoolchildren, whereas the prevalence of eczema and allergic rhinitis has continued to increase.

Anti-Asthmatic Agents↗
PubMed2004

Associations of the IL12B promoter polymorphism in longitudinal data from asthmatic patients 7 to 42 years of age.

BACKGROUND: The IL12B gene encodes the p40 chain of IL-12, a proinflammatory cytokine that antagonizes TH2 expression and hence may play a critical role in the pathogenesis of airway inflammation observed in asthma. A promoter polymorphism of the gene was recently shown to be associated with asthma severity in children but only in heterozygotes. OBJECTIVE: The aim of the present study was to test the hypothesis that the IL12B promoter polymorphism is associated with asthma susceptibility, severity, and related phenotypes in a cohort with longitudinal phenotypic data, from childhood to adulthood. METHODS: Four hundred one 7-year-old children (106 control children, 295 asthmatic children) and 83 10-year-old children with severe asthma were recruited from a 1957 birth cohort. Atopic status and respiratory functions were determined at ages 7, 10, 14, 21, 28, 35, and 42 years. At age 42 years, blood samples were taken from 244 individuals for genotyping and the determination of plasma IgE levels and PHA- and house dust mite-induced IFN-gamma responses. Genotyping was done by the PCR restriction fragment length polymorphism method, using Alu I, and confirmed in 10% of the samples by direct sequencing. RESULTS: The IL12B genotypes were not associated with asthma susceptibility, severity, or atopy at ages 7 and 42 years. Total serum IgE levels at age 42 of men with at least one CTCTAA allele were higher than those homozygous for the GC allele (P = .042), whereas no difference was observed for women. At all ages, female subjects with at least 1 copy of the CTCTAA allele had lower mean percent predicted levels of FEV1 and FVC compared with those without this allele; these differences were significant at ages 10 and 14 years (P < .05) and in the asthmatic subgroup at age 7 years (P = .001). CONCLUSIONS: In this long-term study of asthmatic subjects with comprehensive data on asthma severity, we found no evidence to support the presence of a heterozygote effect of the IL12B promoter polymorphism on the level of asthma in early childhood or adulthood. The polymorphism was also not associated with asthma susceptibility, but the CTCTAA allele may have been associated with elevated serum IgE levels in male subjects and reduced pulmonary function in female subjects in early childhood.

Adolescent↗
PubMed2004

Height prediction from ulna length.

Height is fundamental to assessing growth and nutrition, calculating body surface area, and predicting pulmonary function in childhood. Its measurement is hindered by muscle weakness, joint, or spinal deformity. Arm span has been used as a substitute, but is inaccurate. The objective of the study was to identify a limb measurement that precisely and reproducibly predicts height in childhood. Males (n=1144) and females (n=1199), aged 5 years 4 months to 19 years 7 months, without disability were recruited from Melbourne schools. Height, arm span, ulna, forearm, tibia, and lower leg lengths were measured with a Harpenden stadiometer and anthropometer. Prediction equations for height based on ulna length (U) and age in years (A) were developed using linear regression. Ulna centile charts were developed by the LMS method. For males, height (cm)=4.605U+1.308A+28.003 (R2=0.96); for females, height (cm)=4.459U+1.315A+31.485 (R2=0.94). Intra- and inter-observer variability was 0.41% and 0.61% relative to the mean, respectively. Height prediction equations from tibia, forearm, and lower leg length were calculated. We show that ulna measurement is reproducible and precisely predicts height in school-age children. It appears to be superior to arm span measurement when neuromuscular weakness, joint, or spinal deformity exists. Ulna growth charts should facilitate growth assessment.

Adolescent↗
PubMed2003

Prediction of childhood pulmonary function using ulna length.

Pulmonary function is important in neuromuscular weakness. In children, height determines normal values. Height measurement is unreliable when neuromuscular weakness or spinal deformity is present. The aim of this study was to accurately predict pulmonary function from a limb segment measurement that is precise and reproducible. Normal males (n = 1,144) and females (n = 1,199), 5.3 to 19.6 years old, were recruited from Melbourne schools. Height, weight, ulna, forearm, tibia, and lower leg lengths were measured using a Harpenden stadiometer and calipers, and electronic scales. Three maximal expiratory maneuvers were performed. Limb measurements were highly reproducible. Linear regression on log-transformed FEV1 and FVC was used to develop prediction equations from limb measurements and age. In males FEV1 = exp (0.071 x U + 0.046 x A - 1.269), r2 = 0.86; FVC = exp (0.77 x U + 0.041 x A - 1.285), r2 = 0.86 and in females FEV1 = exp (0.072 x U + 0.041 x A - 1.272), r2 = 0.84; FVC = exp (0.078 x U + 0.037 x A - 1.315), r2 = 0.83 (U refers to ulna length and A refers to age). Precision is similar to equations using height. Ulna measurement is accessible in wheelchair-bound children. Using ulna length to predict pulmonary function should facilitate respiratory assessment in children whose height is difficult to measure.

Adolescent↗
PubMed2003

Repeatability of bronchial responsiveness to mannitol dry powder in children with asthma.

Our objective was to determine the repeatability of bronchial responsiveness to mannitol dry powder (MDP) as an objective marker of asthma in children. MDP challenge was performed in children with stable asthma at the same time of the day on two separate occasions within a week. The test was terminated after a 15% fall of forced expiratory volume in 1 sec (FEV1) and the provocative dose to produce a 15% fall in FEV1 (PD15) were calculated. Seventeen children (aged 9-16 years) on inhaled corticosteroids (200-1,500 mcg) were studied. Mean baseline FEV1 before the challenges were 95% (81-119) and 96% (74-121), respectively, with a standard deviation of differences of 5.2%. PD(15) values ranged from 7-387 mg, with a geometric mean of 38 mg for the first and 49 mg for the second test. Of the 17, all but two pairs of tests achieved a PD15 within one dose of capsules. Four children had a negative challenge on two occasions. A high relative reliability was reflected by a concordance coefficient of 0.86. In conclusion, MDP is a convenient challenge which is easy to administer and is well-tolerated by children. It is a highly reproducible test of airway responsiveness in children with moderate to severe persistent asthma on inhaled corticosteroids within 7 days under laboratory conditions.

Administration, Inhalation↗
PubMed2003

Major haemoptysis in children with cystic fibrosis: a 20-year retrospective study.

BACKGROUND: Major haemoptysis occurs in approximately 1% of children with cystic fibrosis (CF). This report describes management and follow-up of these children at a tertiary centre in Australia. METHODS: Retrospective review of medical records from 1980-1999. RESULTS: Fifty-one children (45% female) had major haemoptysis (102 episodes). Mean age at first episode was 15 years (range 7-19) and mean FEV(1) was 56% predicted (range 14-98). Massive life-threatening haemoptysis was not confined to those with severe lung disease (FEV1 < 50% predicted). Bronchial artery embolisation (BAE) was more likely to be the initial treatment for those with massive haemoptysis and chronic recurrent bleeding tended to be treated conservatively (P = 0.01). Overall, 52 BAE were performed in 28 children with an immediate success rate of 98%; 13 children (46%) had repeated BAE. Four patients died as a direct result of severe haemoptysis. Mean follow-up was 54 months (range 0.5-183). Median survival time (Kaplan-Meier estimate) after first haemoptysis was 70 months, with a significantly longer survival for male patients independent of age (RR 3.8; 95% CI 1.7-8.8; P = 0.001). Median survival time following initial treatment with BAE was longer (103 months) compared to conservative treatment (52 months, P = 0.09). CONCLUSIONS: Massive haemoptysis was unrelated to the severity of lung disease and was more likely to be treated with embolisation. BAE was highly effective, however, 46% of the children required re-embolisation at some time, which is similar to the recurrence risk for major hemoptysis treated conservatively on longer term follow-up.

Adolescent↗