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R Dinwiddie

Publications and source records attributed to R Dinwiddie.

At least 37 records · Page 2Linked to original sources
PubMed1998

A step in the right direction: assessing exercise tolerance in cystic fibrosis.

Exercise tolerance may be reduced in patients with cystic fibrosis, but it is not always possible to predict this from standard lung function measurements. Formal exercise testing may, therefore, be necessary, and the test should be simple and readily available. We have developed a "3-minute step test" and compared it with the standard 6-minute walking test. Subjects stepped up and down a 15-cm-high single step at a rate of 30 steps per minute for 3 minutes. The effect of the step test on spirometry was tested first in 31 children with CF (mean age, 12.0 years), who had a mean (range) baseline forced expired volume in 1 second (FEV1) of 64% (18-94%) of predicted values. The step test was then compared with the standard 6-minute walk in a further 54 patients with cystic fibrosis (mean age, 12.5 years), with mean (range) baseline FEV1 of 61% (14-103%) of predicted values. Outcome measures were minimum arterial oxygen saturation (SaO2), maximum pulse rate, and the modified Borg dyspnea score. Post-step test spirometry showed mean (95% CI) changes of -1.1% (-6.0 + 3.9%) for forced vital capacity, of -1.6% (-4.2 + 1.1%) for FEV1, and +0.25% (-2.8 + 3.3%) for peak expiratory flow, although 5/31 children showed >15% drop in one or more parameters. The step and walk tests both produced significant changes (P < 0.0001) in all outcomes, with a mean (range) minimum SaO2 of 92% (75-98%) versus 92% (75-97%), a maximum pulse rate of 145 b.p.m. (116-189) versus 132 (100-161), and a Borg score of 2.5 (0-9) versus 1.0 (0-5), respectively. Comparison of the two tests showed that the step test increased breathlessness (mean change Borg score, 2.3 vs. 0.8; P < 0.0001) and pulse rate (mean change, 38% vs. 24%, P < 0.0001) significantly more than the walk, whereas the decrease in SaO2 was similar (mean change, -2.9% vs. -2.6%; P = 0.12). Some patients with a significant drop in SaO2 (>4%) would not have the decrease predicted from their baseline lung function. Reproducibility for the two tests was similar. The step test is quick, simple and portable, and is not dependent on patient motivation. Although the step test is more tiring, its effect on SaO2 is similar to the 6-minute walking test. It is a safe test that may prove to be a valuable measure of exercise tolerance in children with pulmonary disease, although longitudinal studies are now needed.

Adolescent↗
PubMed1997

Randomised controlled trial of inhaled corticosteroids (fluticasone propionate) in cystic fibrosis.

BACKGROUND: Controlling lung inflammation may be the key to improving morbidity and mortality in cystic fibrosis. OBJECTIVE: To assess the effects of inhaled corticosteroids on lung inflammation in cystic fibrosis. DESIGN: Double blind placebo controlled randomised sequence crossover trial. Fluticasone propionate (400 micrograms/day) was given as a dry powder inhaler for six weeks with a four week washout period before crossover. OUTCOME MEASURES: Sputum inflammatory markers (interleukin-8, tumour necrosis factor-alpha (TNF-alpha) and neutrophil elastase-both free and bound to alpha 1-antiprotease), sputum interleukin-10, lung function, and symptomatology. SUBJECTS: Twenty three children from a regional cystic fibrosis centre were enrolled into the study, with mean age 10.3 years (range 7 to 17 years) and mean baseline forced expiratory volume in one second (FEV1) of 64% (range 21% to 102%) predicted for sex and height. One patient was excluded for non-compliance to the study protocol. RESULTS: No significant benefit was shown for the use of fluticasone propionate in any of the outcomes. For sputum interleukin-8 there was an estimated true treatment median difference of 142 pg/ml (95% confidence interval (CI) 8 to 2866 pg/ml) in favour of placebo; while for maximal expiratory flow at 25% (MEF25%) remaining forced vital capacity predicted for sex and height there was a 15 percentage points (pp) (95% CI 4 to 26 pp) mean treatment difference in favour of placebo. Sputum interleukin-10 was undetected in any samples and unaffected by fluticasone propionate. Neither atopic status, baseline FEV1, nor concomitant DNase therapy had any effect on response to treatment. CONCLUSIONS: Lack of benefit from fluticasone propionate was most likely due to failure of the drug to penetrate the viscid mucus lining the airways. It is suggested a large multicentre trial with higher doses given for a longer time by a different delivery system is required to assess efficacy.

Administration, Inhalation↗
PubMed1997

Lung involvement in the multisystem syndrome CHARGE association.

The CHARGE association is a multisystem syndrome, with a wide range of phenotypic expression, causing mortality, especially in childhood. We performed a hospital audit, in order to quantify the pulmonary implications, in 28 boys and 19 girls aged 0.02-23 yrs, with a definite diagnosis of CHARGE. A review of the records of these children with CHARGE association revealed that aspiration was common during infancy, as a result of inco-ordination of swallowing and gastro-oesophageal reflux. Aspiration was suspected in 22 of the 47 cases (47%), recurrent chest infections occurred in 22 cases (47%), and lung involvement contributed to 7 out of 17 deaths (41%). We conclude that respiratory morbidity and mortality is common in CHARGE, and decreases with age. Early diagnosis and treatment affords the best prognosis.

Abnormalities, Multiple↗
PubMed1996

Pulmonary alveolar microlithiasis in childhood: diagnosis by transbronchial biopsy.

A 7-year-old girl of Arabic origin by consanguineous parents presented with a miliary pattern on chest x-ray. Transbronchial lung biopsy revealed a histological diagnosis of pulmonary alveolar microlithiasis, a condition rarely described in childhood. This report highlights the clinical and radiological features, documents the transbronchial lung biopsy as a useful diagnostic procedure, and suggests a possible genetic etiology with autosomal recessive inheritance.

Bronchoalveolar Lavage Fluid↗
PubMed1996

Reduced upper airway nitric oxide in cystic fibrosis.

Nitric oxide (NO) produced within the respiratory tract is detectable in exhaled and nasal air. Its synthesis may be induced by inflammatory cytokines and reduced by glucocorticoids. Increased concentrations have been found in asthma and bronchiectasis. In this study, NO concentrations were determined in 63 children with cystic fibrosis, of whom 13 were on inhaled steroids (mean age 13.3 years) and 50 were not (mean age 12.3 years); 57 normal children (mean age 12.2 years) were also studied. NO was measured by chemiluminescence analyser, exhaled NO following a relaxed vital capacity manoeuvre, and nasal NO with the breath held following a full inspiration. Mean concentration of exhaled NO in cystic fibrosis patients (no steroids) was 4.7 parts per billion (ppb) (95% confidence interval (CI) 4.0 to 5.3); this did not differ from values in normal children (mean 4.8 ppb, 95% CI 3.8 to 5.8) or in cystic fibrosis patients on inhaled steroids (mean 3.6 ppb, 95% CI 2.5 to 4.8). Nasal concentrations were significantly lower in cystic fibrosis patients, with or without inhaled steroids, than in normal children (cystic fibrosis, no inhaled steroids: 460 ppb, 95% CI 399 to 520; cystic fibrosis, inhaled steroids: 522 ppb, 95% CI 313 to 730, v normal children: 1024 ppb, 95% CI 896 to 1152, p < 0.0001). Considering the inflammatory nature of cystic fibrosis, it is surprising exhaled NO levels were not increased, but this may have been due to alteration in NO diffusion through thick mucus. The low nasal NO concentrations, which are probably the result of impaired flow from the paranasal sinuses, may contribute to the recurrent respiratory infections typical of cystic fibrosis.

Administration, Inhalation↗
PubMed1995

Testing carrier status in siblings of patients with cystic fibrosis.

Altogether 114 parents of patients attending a cystic fibrosis clinic and 27 regional genetics units were surveyed for their views on whether healthy siblings should be tested for carrier status during childhood. Most parents wanted to know their child's carrier status and felt it was their right; almost all would tell the children if they were carriers. However, 37% of the units never tested siblings and 40% said the parents had no right to this knowledge. Furthermore, 60% would withhold the information from parents.

Adolescent↗
PubMed1994

Fibrosing alveolitis and desquamative interstitial pneumonitis.

We report the experience with and evaluation of treatment strategies in fibrosing alveolitis and desquamative interstitial pneumonitis (FA/DIP) over the last 16 years by a review of all cases referred to a tertiary referral center. There were 25 cases, 16 boys and 9 girls (mean age at onset, 2.3 years; range, 7 days to 11.6 years). In each case the diagnosis was confirmed by open lung biopsy at a mean age of 3.3 years (range, 7 weeks to 15.1 years). Presently features were tachypnea (19), cyanosis (15), cough (12), exertional dyspnea (7), recurrent chest infections +/- wheezing (9), and clubbing (8). Four patients recovered without antiinflammatory medication. The others received specific treatment. Of 11 patients given only prednisolone, six improved, two did not, and three died despite treatment. Of five patients receiving only chloroquine, four responded. Five patients received both prednisolone and chloroquine; one died, two responded well. There was poor progress in the remaining two. Of the 10 patients receiving chloroquine six (60%) showed a good response. A younger presentation carried a worse prognosis, but chest radiology at presentation and outcome were not interrelated. Those with mild histological changes all survived, but severe desquamation or fibrosis at biopsy was not related to outcome. In four cases there was a family history (16%). Patients with FA/DIP probably represent a disease spectrum of multiple etiology with a variable prognosis and response to treatment.

Child↗
PubMed1993

High dose Nutrizym 22 in cystic fibrosis.

New high dose pancreatic enzyme preparations could be potentially helpful to cystic fibrosis (CF) patients. The purpose of this study was to compare the efficacy of the new high dose pancreatic enzyme preparation, Nutrizym 22 with the standard preparation Nutrizym GR. Twenty-five CF children (aged 7-16 years) entered the study and 22 completed it; 3 did not, due to non-compliance. All were taking Nutrizym GR for at least 2 weeks before entering the study. A randomised double blind, crossover method using standard Nutrizym GR or double strength Nutrizym 22 capsules was carried out over two consecutive 14-day periods. Crossover analyses of variance showed no statistically significant differences in actual weight gain, appetite, abdominal pain, stool consistency or faecal fat during the prestudy and study periods. It is concluded that half the capsule numbers of the high strength preparation are just as effective as the standard capsule dosage.

Adolescent↗
PubMed1992

Generalized lymphangiomatosis and chylothorax in the pediatric age group.

Four patients with generalized lymphangiomatosis presenting with chylothoraces are described. All four had bone involvement, two had involvement of the spleen, and one of the pericardium. The diagnosis was confirmed by typical radiology, histology, and in three patients by immunohistochemistry. Treatment was mainly palliative. Three patients died within 1/2 to three years of presentation.

Bone Diseases↗