Aeroallergen analyses and their clinical relevance. II. Sampling by high-volume airsampler with immunochemical quantification versus Burkard pollen trap sampling with morphologic quantification.

A comparison was made between the amount of airborne pollen collected by Burkard airsampler and the allergenic activity of particles trapped on glass fibre filters in an Accu-Vol high-volume airsampler. The comparison was made throughout the pollen seasons 1986 to 1989. Both airsamplers were operated 24 h a day. They were placed less than 5 m apart, and estimation of the pollen amount was made on a day-to-day basis during the pollen seasons, and on a weekly basis outside the seasons. The occurrence of the 3 clinically most important allergenic types of pollen, birch, grass, and mugwort, was analysed, and close correlations between the 2 sampling techniques were found (rs 0.5-0.8, p < 0.001). The detected range of counted pollens/m3 was: birch 0-1075, grass 0-156, and mugwort 0-44. By immunochemical analysis we found the corresponding amounts to be 0-80, 0-8, and 0-1 SQ-U/m3, respectively. Pollen counts and immunochemical estimation were compared with the symptom score recordings of allergic persons for birch season 1989 and for grass seasons 1986, 1988, and 1989. A close correlation was found for both sampling techniques for the grass seasons in 1986 and 1989 (rs 0.51-0.61, p < 0.001-0.0001), but a less significant correlation was found for the 1988 grass season, and for birch in 1989 (rs 0.24-0.34, p < 0.001-0.05).

Epidemiology of allergic diseases in children.

The one-year-prevalence rate of bronchial asthma in children varies from 1-3%, when investigated in general practice, to 5-7% in population studies. The prevalence rate is highest in young boys. Eighty percent of the asthmatic children are allergic, house-dust-mite allergy being the most common allergy. The one-year-prevalence rate of rhinitis is 5-10% in general practice, and 10-12% in population studies. Again, the prevalence rate is highest in young boys. About 90% of children with rhinitis symptoms are allergic, with pollen allergy as the most common allergy. Risk factors for developing allergic diseases are many. The predisposition is probably the most prevailing risk factor. Period of birth, sex, race, diet, the presence of other allergic diseases, tobacco smoking, pollution, and allergens in the environment, all these factors alone or in combination almost double the risk. There is no doubt that both asthma and hay-fever prevalences have steadily increased within the last 50 years. Also, admissions to hospitals for childhood asthma have continued to increase, while the mortality of asthma in children has not risen statistically. This increase is in contrast to the effective medication available for both asthma and allergic rhinitis, and to the number of preventive factors known to us today. The time has come to try to change it at all costs. The outcome of allergic rhinitis and asthma shows that only 10% are cured, 50% ameliorate, 30% remain unchanged, and 10% deteriorate. Factors determining the outcome are age, immunotherapy, sex, mother's age at childbirth, infections, other allergic diseases, and signs and symptoms of food allergy.(ABSTRACT TRUNCATED AT 250 WORDS)

[Occurrence of asthma and non-infectious rhinitis in Denmark]. / Forekomst of astma og ikke-infektiøs rhinitis i Danmark.

Population surveys of asthma have shown total asthma prevalence rates of 3.8 (2-5) and 3.2 (3-4) in 1978-1979 and 1987. These figures do not fit with the general statements of an increased asthma prevalence during recent decades. Hospitalization has increased from 1 per 1,000 to 1.6 per 1,000 inhabitants from 1979 to 1987. The annual mortality from asthma has doubled during the last ten years, and is now 3 per 100,000 inhabitants. All epidemiological data about asthma are blurred because of uncertain definitions of asthma. Allergic and vasomotor rhinitis occurs among 10 per cent of the adult population and seems to be recorded by 50 per cent more in 1987 than in 1978-1979, especially among the younger population. Also in rhinitis diagnostic criteria seem to vary in a way that makes estimates of variation over a longer period of time uncertain.

A comparison of airway responsiveness in smokers with chronic bronchitis and in asthmatic subjects.

Fifty-two of 95 smokers with a forced expiratory volume in one second (FEV1) above 70% predicted and with chronic bronchitis were found to have increased bronchial responsiveness, expressed as PC20FEV1, upon challenge with inhaled histamine. The degree of responsiveness was significantly below that found in matched asthmatics, but substantially higher than that reported in normals. The degree of responsiveness was significantly correlated to prechallenge ventilatory capacity, age and tobacco consumption but not to sex. PC40MEF50 showed the same distribution as PC20FEV1, but did not add further information. The slope of the dose response curve expressing the maximum expiratory flow at 50% of vital capacity expired (MEF50) did not correlate with any of the parameters measured. The slope of the FEV1 dose-response curves showed significant correlation with tobacco consumption. The degree of bronchial responsiveness as an indication for future disability needs to be investigated.

A trial of inhaled budesonide on airway responsiveness in smokers with chronic bronchitis.

The aim of the present randomized, double-blind study was to evaluate the effect of inhaled budesonide on daily symptoms, ventilatory capacity, and airway responsiveness in smokers with chronic bronchitis. Twenty-five subjects with a provocative concentration producing a 20% fall in forced expiratory volume in one second PC20(FEV1) less than 2.0 mg.ml-1, by bronchial histamine challenge, were included. Eighteen subjects accomplished the entire 12 week study, eight receiving inhaled budesonide 400 micrograms b.i.d. and ten receiving placebo. Cough decreased significantly in the actively treated group during the treatment period, but no change could be demonstrated in expectoration, dyspnoea, or sleep disturbances. No changes in any of these symptoms were found in the placebo group, and no differences in symptoms scores were found between the groups. No significant differences in ventilatory capacity or bronchial responsiveness could be demonstrated. In conclusion, a moderately high dose of inhaled steroid in eight subjects with chronic bronchitis did not improve the symptom scores, ventilatory capacity, or airway responsiveness to any clinically relevant degree.

[Diagnosis of penicillin allergy. Results of a clinical investigation program]. / Diagnostik af penicillinallergi. Resultater af et klinisk undersøgelsesprogram.

Investigations concerning penicillin allergy (PA) from abroad suggest that considerable overdiagnosing occurs. The absence of standardized commercially available preparations for skin testing and the time necessary for thorough testing are also contributory causes. Fifty patients with suspected PA were investigated with a programme consisting, in serial order, of RAST for IgE to penicillin V and G, a cutaneous test with a commercially available test preparation (Penkit), first with a prick followed by intracutaneous testing and finally with oral provocation. If a positive reaction occurred, the test was discontinued. Six patients (12%) had positive RAST or cutaneous reactions, (1 positive to RAST, 2 to prick and three not until the intracutaneous test), while no patients with negative RAST and cutaneous tests reacted to oral provocation. No generalized allergic reactions occurred during testing. It did not prove possible to predict which patients would react positively on the basis of the case histories. This investigation thus demonstrates that PA is also considerably overdiagnosed in Denmark and that a programme of investigation such as this is suitable for testing for PA and, finally, that the programme of investigation can scarcely be simplified.

Immunochemical estimations of allergenic activities from outdoor aero-allergens, collected by a high-volume air sampler.

To quantify airborne allergens in amorphus and morphological particles, a survey with collection of aero-allergens on glass fibre filters by means of a high-volume air-sampler (HIVOL) was conducted. In preliminary laboratory experiments we compared various filter elution techniques, and the pulverizing elution technique was found to be optimal with regard to yield and convenience. When a surfactant, Tween 20 (0.5% v/v), was added to the elution buffer, a recovery of 80% could be obtained. Allergens in eluates were analysed by means of an IgG-subclass RAST inhibition assay. This immunochemical method for quantification of airborne allergens was validated, as a high recovery of timothy grass pollen allergens was eluted from air filters, and eluates were shown specific by RAST inhibition. The amount of immunochemically measured airborne timothy and birch allergens collected by means of the HIVOL sampler was highly correlated with pollen counts obtained with a Burkard sampler (pollen trap) situated in the same place.

[Penicillin allergy]. / Penicillinallergi.

Patients are often labelled "allergic to penicillin" without adequate reason. Since penicillins are frequently the drugs of choice, this label should not be accepted lightly. The allergic reactions to penicillins are of immediate, accelerated, or delayed-type hypersensitivity. The most serious reactions are those of acute- and accelerated-type, which are both IgE mediated. Ideally, patients suspected of being allergic to penicillins should be tested in succession with RAST, skin testing, and per-oral provocation. Patients with serious infections and documented penicillin allergy should undergo desensitisation. Patients with penicillin allergy have a slightly increased risk of reactions to cephalosporins.

Turbuhaler: a new device for dry powder terbutaline inhalation.

The aim of this study was to compare bronchodilator response and adverse effects of terbutaline when administered with the metered dose inhaler (MDI) Bricanyl and with the dry powder inhaler Bricanyl Turbuhaler (BT). Nine adult patients with bronchial asthma participated. The study was of an open crossover design. At 30-min intervals the patients inhaled increasing doses of terbutaline (0.25 mg to 5.0 mg cumulated) from either the conventional MDI or from the BT. After each inhalation FEV1, FVC, heart rate, muscle tremor and adverse effects were recorded. Both treatments, BT and MDI, resulted in a dose-related increase in lung function, without any statistical difference. Taste sensation, muscle tremor and increase in heart rate were observed in both groups. Because of the design of the BT one may assume that inhalation failure can be avoided.

Prognosis of patients reacting with urticaria to insect sting. Results of an in-hospital sting challenge.

Insect sting challenge in 14 patients with urticarial reaction to last insect sting resulted in two systemic reactions (95% confidence limits 0-6 patients), a reaction rate of 14%. Skin prick test, basophil histamine release, RAST, and allergen-specific IgG, alone or in conjunction, could not indicate the patients to react systemically after sting challenge. Further, the systemic reactions were uninfluenced by type of insect and time elapsed since last insect sting. It is concluded that the reaction to future insect stings cannot be predicted by the immunological tests presently available.

Basophil histamine release in insect venom allergy.

The aim of the present study was to investigate venom-related and venom-non-related immunological reactions in patients stung by bee or wasp. Sixteen consecutive patients (7 with local and 9 with systemic reactions) were tested with skin tests, RAST and basophil histamine release (BHR) test immediately after the insect sting and 2, 4, and 16 weeks later. No test was useful immediately after the insect sting, the "anergic period". In agreement with earlier findings, the SPT was the only allergy test that showed statistically significant differences between patients with local and systemic reactions, although a great overlap was found. Release of histamine from basophils after incubation with anti-IgE also showed statistically significant differences between local and systemic reactions. Further studies are needed, especially measurement of BHR after incubation with anti-IgE before insect stings.

High-dose local steroid treatment in bronchopulmonary aspergillosis. A pilot study.

Two patients with allergic bronchopulmonary aspergillosis (ABPA) have been treated with a high dose (1600 micrograms daily) of inhaled corticosteroid for 18 months. A beneficial effect with regard to asthmatic symptoms was observed in both patients. During the first 14 months of the observation period no significant changes were observed in lung function parameters. Bronchial histamine challenge showed decreased hyperreactivity. IgE decreased in both patients, while specific IgE and IgG remained the same. After 14 months of treatment one of the patients developed severe, acute exacerbation of the ABPA and was treated with high-dose prednisolone and local steroid. The patient is now fully recovered and has continued on local steroid therapy. The other patient had no episodes of exacerbation and remains stable on this treatment.

Allergy to venom from bee or wasp: the relation between clinical and immunological reactions to insect stings.

Sixty-three patients, applying to the casualty ward after a bee or wasp sting, were tested. On the day of admission, and 4 weeks later, blood was sampled to measure specific IgE and IgG against bee and wasp venom and total IgE. Four weeks after the insect sting, all patients were examined with skin-prick test (1, 10 and 100 micrograms/ml), and intracutaneous test (0.05 ml of extract 1.0 microgram/ml). The amount of venom-specific IgE and IgG increased significantly during the 4-week period, venom-specific IgE was most pronounced in patients experiencing the most severe clinical reactions. However, no significant correlations were found between the results of the immunological tests carried out 4 weeks after the insect sting and the clinical reaction upon the insect sting.

Epidemiology of asthma in Denmark.

The epidemiology of asthma in the Danish population is reviewed with reference to research on asthma in general populations, in general/family practice and in hospitals. The prevalence of asthma in Denmark is on the same order as found in national morbidity studies in Britain and the US. The two-peaked prevalence curve suggests that there are two different diseases: childhood asthma, provoked by allergy and temporarily stopping before adulthood, and adult asthma gradually increasing in prevalence until 60 to 70 years of age and due to hyperreactivity. In Denmark, asthma does not appear to be increasing in incidence. With the exception of the very young, seasonal variation is not pronounced and hyperreactivity is thus more dependent on irritants than on seasonally occurring allergens such as pollen. The concomitant prevalence of asthma and allergic rhinitis was similar to rates reported elsewhere. Problems and limitations of sources of data for epidemiologic studies are discussed.

Dose frequency in the treatment of asthmatics with inhaled topical steroids. Comparison between a twice daily and a once daily dosing regimen.

In 23 stable asthmatic patients sensitivity to inhaled beclomethasone dipropionate (BDP) was demonstrated during single blind gradual tapering off of BDP. After a 2 week stabilization period the patients were randomly allocated to receive either 4 puffs of 50 micrograms BDP twice daily (AM/PM) or 8 puffs of 50 micrograms once daily (AM). After 4 weeks the patients were crossed over. Fifteen patients preferred the twice daily regimen, 5 preferred once daily and 3 had no preference (p less than 0.05). During the once daily dosing regimen a decrease in morning and evening peak expiratory flow (p less than 0.05) and an increase in nighttime and daytime symptom score (p less than 0.05) was found, while the number of inhaled beta 2-agonist doses did not change significantly (p = 0.05). It is concluded that a twice daily regimen controls the asthmatic symptoms significantly better than a once daily regimen.