Prevalence of latex allergy in operating room nurses.

The twofold purpose of this study was to assess the prevalence of latex sensitivity in a large group of operating room nurses and to evaluate the relationship between questionnaire responses and skin tests. Of the total target population of 268 operating room nurses, 248 (93%) answered the questionnaire and 197 had skin prick tests to latex (1/10 wt/vol solution). Symptoms associated with glove wearing were acknowledged by 41.1% of nurses. Skin tests to latex were positive in 21 nurses (10.7%), 4.4 times more often in atopic nurses. Among nurses complaining of local symptoms, only 18.6% had positive skin tests. Itching of the hands during glove wearing correlated poorly with latex sensitivity, but correlation with local urticaria was better. Atopic nurses complaining of urticaria had latex allergy in 70% of cases. Thus latex allergy is common in nurses, especially atopic nurses. A questionnaire is unreliable in predicting latex sensitivity and must be supported by latex skin test. More data will be needed to assess the risk of anaphylactic perioperative reactions in operating room nurses.

Validation of an exposure system to particles for the diagnosis of occupational asthma.

STUDY OBJECTIVE: We previously described a closed-circuit system for exposure to particles in humans. This system has three components: a particle generator, an exposure chamber connected to an orofacial mask, and monitors. We describe results of challenges in 56 subjects who underwent challenges with the apparatus using occupational sensitizers in particles. SUBJECTS: Fifty-six consecutive subjects referred for the investigation of occupational asthma to occupational sensitizers in particles were included. The agents were the following: flour and grains (n = 19), cedar (n = 10), psyllium (n = 9), guar gum (n = 9), drugs (n = 3), persulfate (n = 2), and miscellaneous (n = 4). INTERVENTION: The duration of exposure was progressive and varied from one breath to a maximum of 180 min depending on the reaction. When no significant fall in FEV1 occurred after exposure with the aerosolization device, the standard approach of tipping particles from one tray to another was used. RESULTS: Twenty-nine subjects (52 percent) had a significant (greater than or equal to 20 percent) fall in FEV1 after exposure. This includes 18 subjects with isolated immediate reactions, four with dual asthmatic reactions, and two with atypical reactions. In 20/24 instances (83 percent), the percentage of fall in FEV1 did not exceed 30 percent, thus showing that dose-response curves can generally be obtained in a safe way. In all instances except one (26/27 cases), subsequent exposures using the traditional method did not result in significant falls in FEV1. CONCLUSION: This new procedure results in safe tests in terms of the percentage of changes in FEV1 during the immediate reactions and very rare false-negative challenges.

Effects of a constant dose rate of terbutaline on circadian peak expiratory flow, heart rate and systolic arterial pressure in patients with asthma exacerbation.

The purpose of this study was to investigate the effect of a constant infusion rate of terbutaline on circadian bronchial peak expiratory flow rate (PEFR), heart rate and arterial pressure in patients with asthma exacerbation. Fifteen hospitalized asthmatic patients (6 females and 9 males, mean age 43.3 years, mean weight 67.0 kg) were included in this study. In order to reach the desired plasma concentrations of terbutaline immediately, a pharmacokinetic simulation was done. Based on the predicted values thus obtained, an initial 5-min bolus dose of 2.94 micrograms/kg was given to all patients at 7 a.m., i.e. at the beginning of the study. Over the following 24 h (7 a.m. to 7 a.m.), 33 micrograms/kg of terbutaline was infused intravenously at a constant rate with an electric pump. Since severe acute asthma requires corticosteroids, a 40-mg injection of methylprednisolone was given to all patients at 7 a.m. PEFR, heart rate, systolic arterial pressure, side effects and plasma terbutaline levels were recorded at 7 and 10 a.m., 1, 4, 7 and 11 p.m., and 3 and 7 a.m. the following morning. Terbutaline had a significant favorable effect on asthma exacerbation but no circadian rhythm was found in PEFR. Although terbutaline was infused at a constant rate, plasma levels depended on circadian variations.

Occupational asthma: validity of monitoring of peak expiratory flow rates and non-allergic bronchial responsiveness as compared to specific inhalation challenge.

The sensitivity and specificity of monitoring peak expiratory flow rates (PEFR) and bronchial responsiveness to the provocative concentration of histamine or methacholine (PC20) has been determined as compared to specific inhalation challenges in the diagnosis of occupational asthma. A prospective study of 61 subjects referred for occupational asthma to various agents was performed. PEFR was assessed every 2 h during a period away from work for at least 2 weeks. The period at work was 2 weeks, or less if there was increased symptomatology or marked changes in PEFR. At least one PC20 assessment was obtained at work and away from work. Graphs of PEFR and PC20 values were interpreted in blind fashion by three experienced readers. There was complete agreement among the three in 54 out of 61 instances (78%). Twenty five out of 61 subjects (41%) had positive specific inhalation challenges. The best index for comparing results of PEFR with specific inhalation challenges was the visual analysis of PEFR with sensitivity and specificity of 81% and 74%. All of the numerical indices were significantly less satisfactory. We conclude that visual analysis of PEFR is an interesting tool for investigating occupational asthma, although sensitivity and specificity values do not seem satisfactory enough to warrant using it alone.

Is the clinical history a satisfactory means of diagnosing occupational asthma?

In some countries a diagnosis of occupational asthma for medicolegal purposes is made when a questionnaire is suggestive and the individual is exposed to a product known to be a sensitizer. The value of an open questionnaire administered by physicians with experience in occupational asthma is unknown, however. We prospectively assessed all subjects (162) referred to our clinic because their physicians thought their asthma might be work related. The medical questionnaire included questions about the nature of the symptoms (dyspnea, wheezing, cough, and chest tightness) and the timing (worse at work or after a shift at work or improved during weekends or holidays). An initial clinical assessment was set by the physician on a scale that ranged from highly probable to probable, uncertain, unlikely, or absent. Subjects then underwent objective assessment with specific inhalation challenges (n = 72), serial monitoring of peak expiratory flow rates for periods at work and away from work (n = 29), or both (n = 61), to confirm or rule out the diagnosis of occupational asthma. A total of 75 subjects (46%) were shown to have occupational asthma. Symptoms alone (type and timing) did not provide a satisfactory differentiation between those subjects with and those without occupational asthma. For example, 66 of 75 (88%) subjects with occupational asthma said that their symptoms improved during holidays, but 66 of 87 (76%) subjects without occupational asthma experienced a similar improvement.(ABSTRACT TRUNCATED AT 250 WORDS)

[Underestimation of cases of occupational asthma in Provence-Alpes-Côte d'Azur and Corse region]. / Sous-déclaration des cas d'asthme professionnel dans la région Provence-Alpes-Côte d'Azur et la Corse.

To evaluate a possible underestimation of disability claims for occupational asthma in the Provence-Alpes-Côte d'Azur-Corse area, we compared the actual figures collected from 1986 to 1988 to the predicted figures. The latter were computed from the number of exposed subjects in at-risk industries and the prevalence of occupational asthma reported in the literature for each exposure category. From 1986 to 1988, only 44 disability claims were submitted and 25 of them were accepted. These disability claims represent about 2% of the occupational asthma cases which would be expected. The reasons for such a large discrepancy could be a selection bias leading disabled subjects to leave the occupation at risk, a failure by the patient and/or the physician to identify the disease, or a poor compensation system which is not an incentive for performing a disability claim.

Unequal day-night terbutaline i.v. dosing in acute severe asthma: effect on nocturnal bronchial patency, heart rate, and arterial pressure.

Our study investigated the differential effects of continuous or unequal day-night terbutaline dosing on circadian bronchial patency, heart rate, and arterial pressure in severe acute asthma. Forty-five hospitalized asthmatic patients (19 women and 26 men, mean age 45.4 years, mean weight 63.5 kg) were included in this multicenter study. Three groups of patients (corresponding to three dosing schedules) were randomized; the three groups were comparable, since no statistically significant difference was detected in the age, weight, or peak expiratory flow values at the beginning of the study. In order to reach immediately the concentrations of terbutaline corresponding to the desired unequal day-night concentrations, a theoretical pharmacokinetic simulation was done to predict the outcome in terms of the plasma concentrations after the three dosing regimens; the results of this simulation allowed us to calculate the initial bolus dose to be given over 5 min to groups A, B, and C, i.e., 1.47, 2.94, and 4.41 micrograms/kg, respectively. This bolus was given to all patients at 0700 h, the beginning of the study.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevalence of occupational asthma and immunologic sensitization to psyllium among health personnel in chronic care hospitals.

Psyllium is a high molecular weight laxative that can cause occupational asthma among health care workers who prepare this product for chronically ill patients. The prevalence of immunologic sensitization and occupational asthma to psyllium is unknown. We investigated the personnel of four chronic care hospitals, including two where four cases of occupational asthma had been confirmed the year preceding the trial. A questionnaire and skin prick tests with psyllium and various inhalants were administered to 193 of 248 (78%) of the workers who agreed to participate. Seventy-five subjects (39%) had a history of respiratory symptoms in normal life and/or respiratory symptoms and/or rhinoconjunctivitis after handling psyllium. Six (3%) showed skin reactivity to psyllium. Increased specific IgE antibodies were found in 20 of 162 of the sera that were tested (12%). In the second part of the study, a histamine inhalation challenge was performed on 70 of 75 (93%) of the subjects with a history suggestive of asthma and/or occupational asthma and/or skin reactivity to psyllium. Twenty (29%) had significant bronchial hyperresponsiveness. The six subjects with a history suggestive of occupational asthma (n = 3) and/or asthma (n = 6) and/or positive skin test results to psyllium (n = 6) had significant bronchial hyperresponsiveness and increased specific IgE levels. They all underwent specific inhalation challenges with psyllium in the laboratory. Four developed bronchospastic reactions (two immediate and two dual reactions). We conclude that by including the initial four cases reported in the year preceding the initiation of this trial, the prevalence of IgE sensitization to psyllium was between 5 (skin testing) and 12% (increased specific IgE levels).(ABSTRACT TRUNCATED AT 250 WORDS)

Occupational asthma caused by guar gum.

Some vegetable gums have been reported to cause asthma. We describe three subjects who were exposed at work to guar gum, which is derived from the outer part of Cyanopsis tetragonolobus, a vegetable that grows in India. The first subject worked for a pharmaceutical company; the second and third subjects worked at a carpet-manufacturing plant. All three subjects developed symptoms of rhinitis and asthma after the onset of exposure to guar gum. All subjects were atopic and demonstrated mild bronchial hyperresponsiveness to inhaled histamine at the time they were observed. Skin prick tests demonstrated an immediate skin reaction to guar gum. All three subjects had high levels of serum IgE antibodies to guar gum. Specific inhalation challenges in which the three subjects were exposed for short intervals (less than or equal to 4 minutes) to powder of guar gum elicited isolated immediate bronchospastic reactions in two subjects and a dual reaction in the other subject.

[Medico-legal statistics on occupational asthmna in Quebec between 1986 and 1988]. / Statistiques médico-légales sur l'asthme professionnel au Québec de 1986 à 1988.

The authors have carried out a statistical analysis of cases of occupational asthma and other occupational lung diseases submitted to the Ministry of Labour in Quebec between 1986 and 1988. The total number of claims was 913, 993, and 866 respectively for the 3 years of which 61% to 71% were accepted. 41% to 55% were new assessments. Of 228 new claims accepted in 1988, 81 (36%) were for occupational asthma. This number surpassed the number of claims accepted for traditional pneumoconiosis (asbestos = 30, and silicose = 36). Isocyanates were the principle cause of occupational asthma (23% of cases were recognised in 1988) followed by flour, red and white cedar, snow crab process workers, and various pharmaceutical products and grains. In comparison with statistics in 1977, one noticed there was a large reversal of the frequency of certain occupational lung diseases that are recognised, because at that time asbestosis and silicosis were the principle causes of claims put forward and accepted. The authors discuss the statistical bias of occupational lung disease obtained by medico-legal agencies. Although occupational asthma has not been the object of the systematic screening program in the work place and although there is a tendency for workers to avoid or abandon their occupation more often than in the traditional pneumoconioses current protection is sufficient in Quebec to motivate individuals who are possibly suffering from occupational asthma to put in a claim for compensation.

Specific serum antibodies against isocyanates: association with occupational asthma.

Although increased levels of specific IgE and/or IgG antibodies have been documented in individual cases of occupational asthma caused by common types of isocyanates (hexamethylene diisocyanate [HDI] and diphenylmethane diisocyanate [MDI]), the frequency among workers with occupational asthma is still unknown. The sera of 62/65 workers referred for specific inhalation challenges with isocyanates were analyzed for the presence of specific antibodies to the relevant isocyanate. Most workers (39, 63%) were exposed to HDI, some to MDI (17, 27%), and a few to toluene diisocyanate (six, 10%). Specific inhalation challenges were positive in 29 subjects, eliciting either immediate (seven), early late (two), late (13), or dual (seven) reactions. Specific inhalation challenges were more often positive in those subjects with increased nonspecific bronchial responsiveness. Twenty-nine subjects demonstrated increased levels of specific IgE and/or IgG antibodies to isocyanates in the absence of antibodies against human serum albumin (increased IgE only, no subject; IgG only, 20; both IgE and IgG, nine subjects). Although there was a loose association between the results of specific inhalation challenges and levels of specific IgE, the association was much better with the level of specific IgG. Indeed, 21 of the 29 subjects (72%) with positive challenges had increased levels of specific IgG, whereas 25 of the 33 subjects (76%) with negative challenges had normal levels of antibodies. The association was significant with both HDI and MDI. The levels of antibodies were not significantly associated with the type of temporal reaction.(ABSTRACT TRUNCATED AT 250 WORDS)

New methodology for specific inhalation challenges with occupational agents in powder form.

Numerous agents in powder form (wood dust, flour, antibiotics, drugs, etc.) can cause occupational asthma. The diagnosis is generally confirmed by specific inhalation challenges in a special challenge room. There are several pitfalls to the procedure: 1) subjects may be exposed to high concentrations of particles; the concentrations of particles may be higher than the threshold limit value-short term exposure level (TLV-STEL), possibly resulting in severe or irritant reactions; 2) the exposure is erratic. To overcome these problems, a new device for aerosolization of powders has been developed. This apparatus consists of three parts: a particles generator, an aerosol delivery system connected to an orofacial mask, and monitors - a photometer and a cascade impactor. Information on the concentration and size distribution of inhaled particles can therefore be obtained. We performed specific inhalation challenges with this apparatus on 20 subjects suspected of having occupational asthma. The concentration of particles was generally below or close to the TLV-STEL and information was obtained on the proportion of particles with a diameter less than 10 mu. Falls in forced expiratory volume in one second (FEV1) were progressive with each increase in the duration of exposure. The five subjects who had negative reactions to exposure were asked to tip the relevant product from one tray to another in the traditional realistic way. All had negative responses. We conclude that this new procedure offers advantages over the traditional method as it gives information on the concentration and size distribution of inhaled particles and makes the drawing of a dose-response curve possible, both of which may improve the safety and accuracy of the test.

[Is there an urban factor in asthma and allergy?]. / Existe-t-il un facteur urbain dans l'asthme et l'allergie?

To evaluate if an "urban factor" could be responsible for an increase of asthma and allergic diseases in developed countries, we compared prevalence rates for these conditions in adults living in urban and rural settings. The urban group consisted of 4,008 adults, randomly selected from the 16 districts of the city of Marseille; the rural group consisted of 1,789 adults, representing 85% of the target population living in a small residential town, Trets. The protocol included, after a mass media information, home-visits by public health physicians. These physicians asked a short standardized questionnaire to all adults 18 to 65 years old. Then, in a subgroup of, hay-fever patients, they performed skin tests to grass pollens. The standardized prevalence rates of asthma and related symptoms, and hay fever, was very similar in both settings. Thus, this study does not support the hypothesis that there is a urban factor in asthma and allergic diseases. In the literature, several studies point out a higher prevalence of these diseases in an urban setting. But these studies have been performed several years ago, when there was a larger difference in air pollutants concentrations between urban and rural settings.

[Clinical and spirometric repercussions of chronic exposure to air pollutants in children in the region of the Gardanne coal-basin]. / Répercussions cliniques et spirométriques d'une exposition chronique aux polluants atmosphériques chez des enfants de la région du bassin de Gardanne.

Our goal was to evaluate the long-term effects of exposure to air pollutants in schoolchildren living in the Gardanne coal-basin. The group consisted of 193 children 9 to 11 years old, 128 living in polluted communities, 65 in low polluted communities. The protocol included a standardized questionnaire and a spirometric evaluation. The prevalence of pulmonary and E.N.T. symptoms was higher in the polluted communities, but a statistically significant difference was only observed for the symptom "wheezing in the chest". The spirometric values, FEV1 and FVC, were very similar in both areas. It is likely that spirometric abnormalities will appear later in those schoolchildren. Indeed, in the same area, studies performed in groups of housewives have demonstrated a higher prevalence of respiratory symptoms, as well as spirometric abnormalities in subjects living in high polluted communities.

[Prevention of infections in chronic bronchitis using vaccination and/or immunomodulation]. / Prévention des infections chez les bronchitiques chroniques par la vaccination et/ou l'immunomodulation.

Polyvalent antimicrobial vaccines have been widely used in chronic bronchitis for nearly fifty years without their effect or mechanism of action always being well understood. The polysaccharide vaccines, in particular pneumococcal, are better defined chemically and in their mode of action. However, it does not seem that ordinary chronic bronchitis is a good indication for these vaccines. The immunomodulators, extracts of the cell wall of certain bacteria, are aimed at increasing the host's defence capacity in a non-specific manner. The addition of ribosomes may favour specific and non-specific immunomodulation. Certain vaccines have shown their efficacy in reduction of infective episodes in chronic bronchitis. However, other studies ought to be undertaken to obtain purified products which are not toxic and are yet more effective. Finally, it is necessary to have better knowledge of the mode of administration and of the doses administered corresponding to the optimal efficacy of the vaccines.

Relationship between skin reactions to common allergens and non-specific bronchial reactivity in young healthy subjects.

In patients with respiratory symptoms, several studies have provided data supporting the hypothesis that there is a casual relationship between allergen exposure and variations in bronchial reactivity. In order to determine if this relationship holds when atopy is defined only on the basis of positive skin tests to common allergens, we compared bronchial reactivity in a group of twelve healthy subjects with positive skin tests and twenty-eight healthy subjects with negative tests. The two groups were comparable in terms of gender, age, smoking habits and family history of atopic diseases. The slopes of the dose-response curves, using airway conductance as an index of response, were similar in the two groups. Thus, in this healthy group of subjects, there was no relationship between skin and bronchial reactivity. It can be hypothesized that, if genetic factors determine bronchial reactivity, such reactivity might not be revealed until skin-test positive subjects have received repeated bronchial stimulation through inhalant allergens.

Allergy to suxamethonium: persisting abnormalities in skin tests, specific IgE antibodies and leucocyte histamine release.

Twenty-one patients, who had previously experienced an anaphylactic reaction to suxamethonium during general anaesthesia, were selected for this study. Initially, skin tests with muscle relaxants were carried out in the twenty-one patients, detection of specific anti-choline IgE in nineteen, and leucocyte histamine release in seventeen. These three tests were then repeated between 1 year and 4 years after the initial evaluation. In the majority of patients, sensitization to the muscle relaxants persisted for more than 1 year after the anaphylactic reaction. Only three patients out of twenty-one (4%) had negative skin tests when retested 1-4 years later. A reduction in leucocyte histamine release was noticed in one of the seventeen retested patients (6%). Modifications of anti-choline IgE were observed in five of nineteen patients (26%). The persistence of sensitization to suxamethonium may result from repeated stimulation by occasional contacts with quaternary ammonium compounds. This study demonstrates the reliability of skin tests, leucocyte histamine release and detection of anti-choline IgE to diagnose allergic reactions to suxamethonium, even when they are performed a long time after the initial anaphylactic reaction.