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P Cullinan

Publications and source records attributed to P Cullinan.

At least 73 records · Page 4Linked to original sources
PubMed1998

Specific IgE to isocyanates: a useful diagnostic role in occupational asthma.

BACKGROUND: Isocyanates are the most frequent cause of occupational asthma in industrialized countries. OBJECTIVE: We sought to investigate the utility of specific IgE measurement in the diagnosis of isocyanate-induced asthma. METHODS: Fifty-eight of 101 patients referred for investigation were diagnosed as having isocyanate-induced occupational asthma by means of history, serial peak flow records, and bronchial provocation tests. Specific IgE antibodies to toluene diisocyanate:human serum albumin (HSA), diphenylmethane diisocyanate:HSA, and hexamethylene diisocyanate: HSA were measured in all patients by Phadebas RAST. RESULTS: Twenty patients had a RAST ratio of 2 or greater to at least one isocyanate. Thirteen (28%) of the 46 patients with a positive provocation test response had a RAST ratio of 2 or greater, and nine (20%) had a RAST ratio of 3 or greater. Raising the RAST cut-off from 2 or greater to 3 or greater reduced its sensitivity but increased the specificity of the test to 100%. RAST measurement was most likely to be positive within 30 days of exposure. Serial measurements suggested that the half-life of the IgE antibodies was approximately 6 months. Evidence of cross-reactivity between isocyanate RAST responses was found in eight subjects. CONCLUSION: Specific IgE to isocyanates is a more specific than sensitive index of occupational asthma. With a RAST score of 3 or greater, it is wholly specific and therefore diagnostic of isocyanate-induced asthma. The sensitivity of specific IgE measurement is highest when blood is taken less than 30 days from last exposure, which is consistent with the observed half-life.

Adolescent↗
PubMed1998

Stepwise health surveillance for bronchial irritability syndrome in workers at risk of occupational respiratory disease.

OBJECTIVES: Questionnaires, lung function tests, and peak flow measurements are widely used in occupational health care to screen for subjects with respiratory disease. However, the diagnostic performance of these tests is often poor. Application of these tests in a stepwise manner would presumably result in a better characterisation of subjects with respiratory disease. METHODS: Cross sectional data from workers exposed to acid anhydrides, to laboratory animals, and to flour dusts were used. Sensitivity and specificity were calculated from cross tables of different (combinations of) tests for bronchial hyperresponsiveness and bronchial irritability in the past four weeks (BIS). From sensitivity and specificity likelihood ratios were computed and change in probability of BIS was calculated. RESULTS: The prevalence of BIS was 7%, 7%, and 5%, respectively. In all groups questionnaire data provided excellent sensitivity but poor specificity, which was inherent on the broad definition of symptoms. Adding the forced expiratory volume in one second/forced vital capacity (FEV1/FVC) ratio yields almost perfect specificity, and peak expiratory flow (PEF) variability is intermediate in populations in which smoking induced or non-allergic respiratory diseases predominates. In occupational groups in which asthma is a problem, adding PEF measurements will optimise sensitivity and specificity in detection of BIS. The probability of BIS for subjects with a negative combined test outcome was lower than the probability before testing. Subjects with a positive combined test outcome had a probability of BIS after the tests at least three times the probability before. CONCLUSIONS: Combined testing yields better sensitivity and specificity. An advantage of combined testing is an economy in the effort to screen for subjects with BIS. Combined testing resulted in more detailed estimation of the probability of BIS.

Anhydrides↗
PubMed1997

Respiratory morbidity 10 years after the Union Carbide gas leak at Bhopal: a cross sectional survey. The International Medical Commission on Bhopal.

OBJECTIVE: To examine the role of exposure to the 1984 Bhopal gas leak in the development of persistent obstructive airways disease. DESIGN: Cross sectional survey. SETTING: Bhopal, India. SUBJECTS: Random sample of 454 adults stratified by distance of residence from the Union Carbide plant. MAIN OUTCOME MEASURES: Self reported respiratory symptoms; indices of lung function measured by simple spirometry and adjusted for age, sex, and height according to Indian derived regression equations. RESULTS: Respiratory symptoms were significantly more common and lung function (percentage predicted forced expiratory volume in one second (FEV1), forced vital capacity (FVC), forced expiratory flow between 25% and 75% of vital capacity (FEF25-75), and FEV1/FVC ratio) was reduced among those reporting exposure to the gas leak. The frequency of symptoms fell as exposure decreased (as estimated by distance lived from the plant), and lung function measurements displayed similar trends. These findings were not wholly accounted for by confounding by smoking or literacy, a measure of socioeconomic status. Lung function measurements were consistently lower in those reporting symptoms. CONCLUSION: Our results suggest that persistent small airways obstruction among survivors of the 1984 disaster may be attributed to gas exposure.

Accidents, Occupational↗
PubMed1997

Inferences from occupational asthma.

Occupational asthma-asthma induced by an agent inhaled at work-provides a valid model for the examination of the more general environmental causes of asthma. In many instances, definable populations exposed to a novel allergen in the workplace at concentrations that are relatively easily measured develop IgE-associated asthma and characteristic eosinophilic bronchitis. Carefully designed epidemiological studies suggest that the incidence of IgE antibody and asthma is highest in the first one to two years of exposure; and that the risk is directly related to the intensity of airborne allergen exposure. The relationship between exposure and outcome is modified both by concurrent cigarette smoking and by genotype, although the details of this latter interaction remain unclear. Symptoms, airway hyper-responsiveness and airway inflammation may persist for several years after avoidance of exposure to the initiating agent. If the relevance of the model is accepted then these insights require testing and further investigation, both within the field of occupational asthma and, by extension, in the wider field of asthma in the general environment.

Animals↗
PubMed1997

Clinical responses to ingested fungal alpha-amylase and hemicellulase in persons sensitized to Aspergillus fumigatus?

alpha-Amylase and hemicellulase, derived from culture of Aspergillus species, are commonly added to flour as improvers during baking. Two cases of women occupationally sensitized to alpha-amylase who developed allergic symptoms after eating baked bread have been reported. With a randomized, controlled study design, we have investigated whether similar responses occur in those sensitized to Aspergillus species. Seventeen subjects with positive skin prick tests to Aspergillus fumigatus were studied. Symptomatic and physiologic responses after ingestion of bread baked with alpha-amylase and hemicellulase were compared, in a crossover fashion, with those after ingestion of bread baked without enzymes. No increase in respiratory or other symptoms, lung function, or nonspecific bronchial hyperreactivity was reported after ingestion of the enzyme-containing bread. We conclude that important clinical reactions to alpha-amylase and hemicellulase in baked bread do not frequently occur in those sensitized to Aspergillus species.

Adult↗
PubMed1994

Work related symptoms, sensitisation, and estimated exposure in workers not previously exposed to flour.

Findings are presented from the initial cross sectional phase of a cohort study of employees exposed to flour in bakeries or mills. Of 401 eligible workers in seven sites 344 (86%) were surveyed; symptoms assessed by self completed questionnaire, and sensitisation measured by the response to skin prick tests, were related to intensity of exposure both to total dust and to flour aeroallergen. Among 264 subjects without previous occupational exposure to flour, work related symptoms which started after first employment at the site were related to exposure intensity, especially when exposure was expressed in terms of flour aeroallergen. The relations with eye/nose and skin symptoms were independent of atopic status and cigarette smoking. Positive skin test responses to mixed flour and to alpha amylase were also more frequent with increasing exposure intensity, although this was confounded by atopic status. There was only a weak association between symptoms and specific sensitisation.

Adult↗
PubMed1994

Work related symptoms, sensitisation, and estimated exposure in workers not previously exposed to laboratory rats.

Findings are presented from the initial cross sectional phase of a cohort study of employees exposed to laboratory rats. Of 366 eligible workers at four sites 323 (88%) were surveyed; symptoms assessed by self completed questionnaire and sensitisation measured by the response to skin prick tests were related to intensity of exposure both to total dust and to rat urinary aeroallergen. Among 238 workers, without previous occupational exposure to rats, work related symptoms, which started after first employment at the site were related to exposure intensity (expressed either in terms of dust or of aeroallergen) at the time of onset of symptoms. These relations were stronger in atopic subjects but were unrelated to smoking. Positive skin tests to rat urinary extract were also more frequent with increased exposure, a relation found in both atopic subjects and in smokers. There was a strong association between work related symptoms and specific sensitisation.

Adult↗
PubMed1994

Fibrosing alveolitis associated with systemic sclerosis has a better prognosis than lone cryptogenic fibrosing alveolitis.

Fibrosing alveolitis associated with systemic sclerosis (FASSc) is considered to be histologically and radiologically indistinguishable from lone cryptogenic fibrosing alveolitis (CFA). To date, the natural history of the two diseases has not been compared directly in large groups of patients followed at a single institution. We evaluated the survival of 205 patients with CFA and 68 patients with FASSc. Deaths during the follow-up period were reported in 142 patients with CFA (70%) and in 11 patients with FASSc (16%). Unadjusted survival from the onset of dyspnea was less in CFA than in FASSc (odds ratio, 3.3; p < 0.001); this difference persisted after adjustment for age of onset of dyspnea and smoking history. Survival from presentation was less in CFA (odds ratio approximately 3.3) after adjustment for age of presentation, smoking history, and initial pulmonary function indices. These differences persisted when analysis was confined to patients with histologic confirmation of fibrosing alveolitis and after adjustment for treatment. In patients undergoing computed tomography (CT) of the lungs, survival was less in CFA after adjustment for extent of abnormal lung on CT and CT pattern of disease (odds ratio, 3.9; p < 0.001). These findings indicate that despite their histologic and radiologic similarities, lone CFA and FASSc have different courses.

Adult↗
PubMed1994

Fibrosing alveolitis in systemic sclerosis. Bronchoalveolar lavage findings in relation to computed tomographic appearance.

Fibrosing alveolitis in systemic sclerosis is histologically identical to lone cryptogenic fibrosing alveolitis (CFA) (idiopathic pulmonary fibrosis). The inflammatory cell content of bronchoalveolar lavage (BAL) samples has been used as a guide to prognosis and treatment in CFA. In this study, the relationship was explored between BAL findings and the extent and pattern of disease within the lavaged lobe, as judged by thin-section computed tomography (CT), in systemic sclerosis. Thirty-eight nonsmoking patients were studied; none had been treated with corticosteroids or immunosuppressive agents, and 11 had no evidence of fibrosing alveolitis on CT. BAL neutrophils were markedly increased in association with extensive disease on CT compared with less extensive disease (p < 0.001) and normal appearances (p < 0.001); the extent of a reticular pattern on CT (denoting fibrosis) correlated with the neutrophil percentage count (p < 0.005) and total neutrophil count/ml (p < 0.01). BAL eosinophils were increased in less extensive as well as in extensive disease when compared with lobes with a normal CT appearance (p < 0.01); eosinophil percentage counts but not total eosinophil counts/ml correlated with the extent of a ground-glass pattern on CT (through to denote inflammation) (p < 0.05). These findings indicate that in systemic sclerosis a BAL neutrophilia is generally associated with extensive fibrotic disease, whereas a BAL eosinophilia is often seen in less advanced disease, particularly when CT appearances suggest lung inflammation.

Bronchoalveolar Lavage Fluid↗
PubMed1993

Aetiological factors in persistent sputum production: a case-control study.

STUDY OBJECTIVE: The aim was to explore the aetiological roles of smoking, occupational exposure, childhood respiratory illness, and atopy in persistent sputum production. DESIGN: This was a case-control study. Data were obtained using a questionnaire administered by two observers blind to the subjects' status. Information was sought on lifetime smoking, occupation, hospital admissions due to respiratory disease, and respiratory disease history. SETTING: Four general practices in south east England in 1990, with a total population of about 30,000. SUBJECTS: Cases were subjects aged 5 to 54 years with sputum production; one control was selected per case, matched by general practice, age, and sex, forming 210 matched pairs (88% response rate). MAIN RESULTS: Cigarette smoking remains an important cause of persistent sputum production: the odds ratio (95% confidence interval) for current smoking was 7.9 (3.6-20.4). A dose-response relationship was confirmed, with falling risk estimates after stopping smoking. The association of sputum production with occupational exposure to respiratory irritants, which was independent of smoking, was confined to men (odds ratio 2.4, 1.0-6.0) and largely attributable to very heavy exposure. Examination of the relationship with early respiratory disease suggested that much, though not all, was attributable to wheezing illnesses first manifest in childhood. CONCLUSIONS: Aetiological fractions derived from the results suggest that in the general population of south east England approximately 68% of all cases of persistent sputum production can be independently attributed to current cigarette smoking, 17% to heavy occupational exposure to respiratory irritants, and 13% to wheezing illnesses first manifest in early childhood.

Adolescent↗
PubMed1993

Assessment and follow up of patients prescribed long term oxygen treatment.

BACKGROUND: Prescription and use of long term oxygen treatment were audited in a large group of patients after more than five years of use of the guidelines for its prescription. METHODS: Patients with a concentrator were interviewed at home with a structured questionnaire in three family health service authorities in East London. Stable oxygen saturation (SaO2) breathing air and oxygen, forced expiratory volume in one second (FEV1) and current and previous dated concentrator meter readings were recorded. A further questionnaire was sent to each patient's general practitioner. Hospital case notes of patients who did not meet the criteria for long term oxygen treatment at reassessment were reviewed. RESULTS: A total of 176 patients were studied; 84% had chronic obstructive lung disease and 19% admitted to continued smoking; 140 patients had seen a respiratory physician but results of respiratory assessment were available to their general practitioner in fewer than 54 cases. FEV1 was < 1.5 1 in 158 patients but in 67 SaO2 was less than 91% breathing air, mainly in patients with chronic obstructive lung disease who had been inadequately assessed. Daily oxygen was prescribed for a median of 15 (range 4-24) hours and measured daily use was 15 (0-24) hours; 74% of patients used more than 12 hours. Only 35 patients had problems with oxygen treatment, but 29 had an undercorrected SaO2 of less than 92% when using their concentrator. CONCLUSIONS: Guidelines for prescription of long term oxygen treatment are largely followed and most patients complied with treatment. Increased communication about respiratory state is required between hospital doctors and general practitioners. Patients need regular reassessments to ensure that hypoxaemia is corrected and that oxygen is appropriately prescribed.

Adult↗