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S Dreborg

Publications and source records attributed to S Dreborg.

At least 91 records · Page 5Linked to original sources

Immunotherapy with Hymenoptera venoms. Position paper of the Working Group on Immunotherapy of the European Academy of Allergy and Clinical Immunology.

Immunotherapy with Hymenoptera venoms is widely used throughout the world and is accepted as an effective treatment for most patients with Hymenoptera venom allergy. There are, however, still some unresolved problems with this form of treatment. At present there is no definite test which makes it possible to identify patients at risk - and thus candidates for immunotherapy - unequivocally. On the basis of prospective studies on the natural history of Hymenoptera allergy, venom immunotherapy is indicated in adults with severe systemic anaphylaxis. It is usually not necessary in patients with large local reactions only. Children with mild systemic reactions, e.g. urticaria, will need immunotherapy only in case of repeated reactions and/or a high risk of re-exposure. The selection of venoms for immunotherapy may lead to some confusion owing to common antigenic determinants shared by venoms of various Hymenoptera species. Many different regimens for immunotherapy have been proposed. At present, the three main are: rush, stepwise or clustered and classical. The maintenance dose of 100 micrograms usually protects from life-threatening reactions. However, in some patients 200 micrograms are necessary for complete protection. The usual interval between maintenance injections is 4 to 6 weeks. In many patients a strong increase of venom specific serum IgG-antibodies usually parallels clinical protection induced by venom immunotherapy, although many exceptions have been reported. Allergic side effects of venom immunotherapy are not rare, especially with honey bee venom and during the initial phase of dose increase. The question of the duration of venom immunotherapy is handled differently: although some authors recommend treatment for life, most suggest treating patients until skin tests and RAST become negative.

Adult↗

High dose grass pollen tablets used for hyposensitization in hay fever patients. A one-year double blind placebo-controlled study.

Previous, placebo-controlled clinical trials with oral hyposensitization in grass pollinosis have been disappointing. Since the results possibly could be explained by too low doses of ingested allergens, the present study was initiated to evaluate the effect of high doses of allergens. Forty-two adults with symptoms in the grass pollen season and with grass pollen sensitivity demonstrated by skin prick test and conjunctival provocation test were included. Enterosoluble tablets were administered daily for 1 year. Twenty-two patients, who completed the study, received placebo and 17 mixed grass pollen allergens from rye grass, timothy grass, cultivated rye and velvet grass. Evaluated either by self-assessment or by symptom and medicine score before and after treatment, the group receiving pollens did not improve clinically compared the controls. During the study, conjunctival sensitivity decreased equally in the two groups, and changes in specific IgE, allergen-induced histamine release from blood cells and skin prick test were insignificant and with no difference between groups. Five patients, who received pollen allergens, had episodes of urticaria or angioedema, and a further three patients on the same treatment had slight gastrointestinal side effects. In conclusion, enterosoluble grass pollen allergens in contrast to birch pollens did not have any therapeutic effect, even in doses more than 4,000 times higher than those used for subcutaneous hypersensitization. The reason may be degradation of allergens before the immune system is reached.

Adolescent↗

Selection of patients for biological standardization as exemplified by standardization of mugwort, goosefoot and English plantain pollen allergen extracts/preparations.

The biological activity of a partly purified, biochemically/immunochemically characterized mugwort pollen allergen preparation and crude pollen extracts of mugwort, goosefoot and English plantain was determined by means of skin prick test (SPT). The patient inclusion criteria with mugwort were a well-defined positive clinical history and a positive SPT. Symptoms related to goosefoot/English plantain pollens are difficult to define, as these weeds flower during the grass pollen season. Thus patients tested with these allergens did not fulfill the most important inclusion criterion for so-called biological standardization. To elicit a wheal of the same size as that produced by histamine 1 mg/ml required 100 to 10,000 times more material from these weeds, than from mugwort and other pollen allergen extracts investigated earlier. One thousand Biological Units/ml (BU/ml) corresponded to 8.3 micrograms dry weight (dw/ml) of the crude and 1.8 micrograms dw/ml of the purified mugwort pollen allergen preparation. Only 7/22 goosefoot-and English plantain-tested patients were positive at conjunctival or nasal challenge. All three weeds showed a similar composition with 5-10 allergens by CIE/CRIE analysis and 10-13 by immunoblotting analysis. One dominating allergen (approx. 15,000 d), could be identified for each weed species by protein gel blot after separation by SDS g-PAGE. There was no other explanation for the difference in biological activity than the criteria of selection. If there is no obvious clinical history, which is the main patient inclusion criterion in biological standardization, then additional criteria should be used.

Adolescent↗

Diagnosis and immunotherapy of mould allergy. VI. IgE-mediated parameters during a one-year placebo-controlled study of immunotherapy with Cladosporium.

The IgE-response was evaluated by skin prick test, bronchial provocation test and RAST in a 1-year placebo-controlled double-blind immunotherapy study. Eleven adult asthmatics were treated with a Cladosporium allergen preparation and 11 comparable patients received histamine placebo. The bronchial sensitivity (PC20) decrease greater than 0.5 log step in 8/11 (73%) Cladosporium-treated versus 3/11 (27%) in the placebo group. Corresponding figures for skin prick test sensitivity was 10/11 (91%) and 1/11 (9%) respectively. Circulating IgE showed a temporary boost in the Cladosporium group and then values approaching the pretreatment value. Only minimal and insignificant changes were found in the placebo-treated patients. Changes in IgE-reactivity were not related to allergen dose, clinical efficacy or to the occurrence of side effects. Some interrelation between changes in skin prick test, bronchial provocation test and RAST was found indicating a differentiated effect of immunotherapy on various IgE compartments. In spite of the pathogenetic role of IgE in allergic diseases, changes in IgE-reactivity do not seem directly involved in the mechanisms underlying the clinical efficacy of immunotherapy but might be of importance in a complex interaction with other immunological parameters.

Adult↗

Results of biological standardization with standardized allergen preparations.

The aim of biological standardization (BS) is to equilibrate the activity (potency) of allergen extracts from different source materials. This was done by performing skin prick tests (SPT) on patients who were sensitive to one of the following 10 allergens: Birch, alder, hazel, timothy, rye grass, velvet grass, cultivated rye, mugwort, D. farinae and Cladosporium herbarum. Patient sensitivity varied within a range of three to four powers of ten for each allergen investigated. The weal size in each patient corresponding to that elicited by histamine 1 mg/ml was calculated using the model log (mean weal diameter) = a + b log (concentration). The correlation coefficients of the regression lines of the allergen dose response relationship were found to be greater than 0.85 in most cases. The median slope for all extracts was 0.24. The slope for Cladosporium was significantly steeper than that for pollens. The amount of material in microgram dry weight (d.w./ml) equal to 1000 biological units/ml (BU/ml) varied within a factor of three between species for all tested purified allergen preparations but Cladosporium. For Cladosporium, about 30 times more material was needed than for D. farinae. When using crude rather than purified material, it was necessary to use five to ten times more to elicit a reaction corresponding to 1000 BU/ml, but the difference was significant only for Cladosporium. The narrow range of allergen concentrations used by us as well as other investigators does not assure positive skin prick test results in all patients with clinical symptoms due to the allergen in question. Skin prick testing should therefore be done over a wide range of concentrations to improve the methods for BS.

Allergens↗

Dose response relationship of allergen, histamine, and histamine releasers in skin prick test and precision of the skin prick test method.

The aim of the present investigation was to study the dose response relationship of allergen, histamine and histamine releasers in skin prick test (SPT) and the precision of the SPT method. In one experiment timothy allergen, histamine HCl, rabbit anti-human-IgE and compound 48/80 were studied in seven patients. In a second experiment timothy allergen and histamine and dog allergen and histamine were investigated in two groups of 10 patients. Histamine HCl 1 and 10 mg/ml induced weals about 15 and 25 mm2 (4.5 and 5.5 mm in diameter), respectively. The precision as expressed by the coefficient of variation was about 25% for histamine and 40% for allergen for weal areas greater than 10 mm2. Calculations of the regression lines to test the dose response relationships were based on the method of least squares. The best fit was to a log/log model. The slopes of allergen, histamine and histamine releasers were essentially parallel within patients. The median slope of allergen was estimated to about 0.4 based on weal areas and 0.2 based on mean weal diameters. Furthermore, no significant differences were found between the lower and upper parts of the dose response curves of allergen and histamine, although there was a tendency towards steeper slopes at lower concentrations. These results show that histamine concentrations greater than or equal to 1 mg/ml should be used as positive control in SPT and that histamine releasers do not offer advantages over histamine as reference substances in SPT. A common slope for the dose response relationship of allergen and histamine can be used for the estimation of skin sensitivity.

Adolescent↗

The precision of intracutaneous skin test with timothy pollen allergen preparation using two different techniques.

The precision of two intracutaneous skin test techniques was investigated by testing three grass pollen-sensitive patients. Twenty tests were performed on the back of each patient with each of two techniques. One method used a glass syringe with a 26 G precision needle attached to micrometer equipment. The other method used a disposable 1-mL plastic syringe with a disposable 20 G needle. The tests were arranged in five rows. Each row consisted of two pairs of tests on each side of the spine. Each pair was considered as duplicate tests at the same site. The two methods were tested on either side of the back. No difference in precision between the techniques was found. The analysis revealed differences in skin reactivity between different areas of the back of individual patients but without a common pattern between patients. These differences, therefore, will not influence test results if several patients are included in the investigation, eg, of the relative potency of allergenic extracts and the allocation of test sites is consistent. The variation found, however, will influence comparisons within the same patient, but in an unpredictable way.

Adolescent↗

Cross-reactivity between deciduous trees during immunotherapy. I. In vivo results.

Thirty-nine children with rhinoconjunctivitis due to birch pollinosis were given immunotherapy for 3 years with a potent, purified pollen preparation made from either birch alone or from a mixture of birch, alder and hazel. The therapy was evaluated with self-evaluation after each season, daily symptom score during the season, conjunctival provocation test and skin-prick test. All children but one considered that their condition had been improved by the treatment. Symptom scores decreased slightly more in the group treated with the mixture than in the group treated with birch only due to symptoms decreasing faster in the mixture treated group after each pollen peak (P less than 0.001). The sensitivity of the conjunctiva and the skin decreased significantly in both groups but without any significant differences between the groups. After 3 years the conjunctival sensitivity correlated strongly to eye symptoms during the season. Immunotherapy with a mixture of birch, alder and hazel appears to be at least as effective as a preparation made from birch only when treating birch pollinosis even in a region where birch is totally dominating among the pollens from deciduous trees.

Adolescent↗

Diagnosis and immunotherapy of mould allergy. III. Diagnosis of Cladosporium allergy by means of symptom score, bronchial provocation test, skin prick test, RAST, CRIE and histamine release.

Thirty-three adult asthmatic patients suspected of mould allergy were investigated by in vivo and in vitro tests in order to establish a specific diagnosis of asthma caused by the mould species Cladosporium. The patients were evaluated by daily symptom scores in the peak Cladosporium season, bronchial provocation test (BPT), skin prick test (SPT), RAST, histamine release from basophil granulocytes (HIST), and crossed radioimmunoelectrophoresis (CRIE), and the results were scored as negative (score 0), equivocal (score 1) or positive (score 2). Based on daily symptom scores and the result of BPT the patients were classified as being manifest allergic (asthma) to Cladosporium (positive allergy), inconclusive or negative. Positive allergy was defined as asthma symptoms oscillating with the spore concentration and a BPT score 2 (positive at allergen concentration less than 10,000 BU). Negative allergy was defined as no asthma symptoms and a negative BPT (score 0) and inconclusive in the case of symptoms and BPT sum of score 1-3. According to the classification a final diagnosis (positive or negative) could be established in 85% of the patients. "False positive" tests were found: for BPT in 27%, SPT 18%, RAST 0%, HIST 18%, and CRIE 0%. The corresponding figures for "false negative" were: BPT 0%, SPT 0%, RAST 27%, HIST 18%, and CRIE 23%. The relative risk of being allergic in spite of a negative test result was 0% for BPT and SPT, and 25-30% with RAST, HIST, and CRIE. In the case of positive test the risk was 90-100%. Excluding BPT, SPT was found to be the optimal single test to predict/rule out clinical allergy. A stepwise combination of positive SPT and positive RAST was found exclusively in patients clinically evaluated as positive, and does not call for an additional BPT. Using a potent allergenic extract a negative SPT excluded clinically important allergy. The primary conclusion of the study, however, is that the final diagnosis of Cladosporium asthma could not be based on a positive BPT alone (due to "false positive"), but only on a combination of clinical symptoms during the spore season and a positive BPT.

Adult↗

A preliminary study of immunotherapy with a monomethoxy polyethylene glycol modified honey bee venom preparation.

Monomethoxy polyethylene glycol (mPEG) modified honey bee venom (HBV) immunotherapy (IT) has been studied in 14 patients allergic to honey bee venom. Doses could be increased more rapidly and higher doses were reached compared to regular venom immunotherapy. No general side effects were seen, although large local swellings were found somewhat more often than with regular HBV. Most patients could easily be switched from the modified to the unmodified venom. Eight patients experienced and tolerated field stings. Skin testing showed a decreased allergenicity of the mPEG-HBV. The mean HBV-specific IgE level was below pre-treatment level already after only 6 weeks of IT. The HBV-specific IgG response was very good.

Adult↗

IgG and IgE antibody patterns after immunotherapy with monomethoxy polyethyleneglycol modified honey bee venom.

Antibody responses to honey bee venom (HBV) were studied in 13 patients during a 4-month course of immunotherapy with monomethoxy polyethyleneglycol (mPEG) modified venom. There was a rise of HBV-specific IgG antibodies as measured by IgG-RAST in all patients and a slight decrease of IgE antibody in most of them. The IgG-antibody responses during mPEG-HBV treatment as examined by crossed radioimmunoelectrophoresis were directed to phospholipase A, hyaluronidase, acid phosphatase and to another allergen, antigen 1. Thus, despite a high degree of mPEG-modification of HBV, the immunogenicity of the most important HBV allergens was retained.

Adult↗

A double-blind, multicenter immunotherapy trial in children, using a purified and standardized Cladosporium herbarum preparation. I. Clinical results.

A double-blind histamine placebo controlled immunotherapy trial was performed to investigate the clinical effect of a purified and standardized Cladosporium herbarum allergen preparation. Thirty children with a clinical history suggesting mould-induced asthma and/or rhinoconjunctivitis were included. The diagnosis was confirmed by positive skin prick test and Phadebas RAST as well as positive bronchial and/or conjunctival provocation test to Cladosporium herbarum. Immunotherapy was given for 10 months in a double-blind manner to randomized groups with either Pharmalgen/Cladosporium herbarum preparation or histamine placebo. Allergic side effects to injections were common, especially during the peak of the mould season (July-September in Scandinavia). In the active group, 13/16 patients experienced general reactions during the first 10 months of treatment. After 6 months of treatment, eye, nose and bronchial symptom scores and peak expiratory flow rates were similar for the groups, maybe because most of the children were also sensitive to many other allergens, including Alternaria alternata. However, medication scores were significantly lower in the treated group (P less than 0.01). Bronchial (P less than 0.01) and conjunctival sensitivity (P = 0.01) were significantly reduced in the Cladosporium-treated group but not in the placebo group after 10 months of treatment. This is the first double-blind clinical trial showing the clinical efficacy of immunotherapy in children with mould-induced asthma.

Adolescent↗

A double-blind, multicenter immunotherapy trial in children, using a purified and standardized Cladosporium herbarum preparation. II. In vitro results.

This double-blind immunotherapy trial in children, using a purified and standardized Cladosporium herbarum allergen preparation, has shown that children with mould asthma and/or rhinoconjunctivitis, responded to immunotherapy with a decrease in specific IgE and a significant increase in specific IgG. There was a marked increase in the ratio specific IgG/specific IgE as a result of active treatment. IgE-CRIE radiostaining patterns showed no pronounced changes after 10 months' active treatment and no "new sensitivities" could be detected in the studied patients. IgG-CRIE radiostaining, primarily directed towards the important allergens, was significantly increased in the active group and particularly towards Ag-12 (partially identical to a previously described major allergen in Cladosporium herbarum, Ag-54). Children treated with histamine placebo showed no change in antibody patterns during 10 months of treatment.

Adolescent↗

Clinical history, skin prick test and RAST in the diagnosis of birch and timothy pollinosis.

The diagnostic efficacy of clinical history (CH), skin prick test (SPT) and RAST was estimated in relation to nasal and conjunctival provocation tests (NPT, CPT) in 69 patients with seasonal rhinoconjunctivitis. The extracts used were freeze-dried, and biologically standardized birch and timothy allergen preparations matched to the extracts on Phadebas RAST discs. Based on single determinations the sensitivity, specificity and predictive values were calculated. There were highly significant (P less than 0.001) correlations between all parameters: NPT, CPT, CH, SPT and RAST. For birch the combination of SPT and RAST made the PTs superfluous as both sensitivity and specificity then reached 100%. With timothy the sensitivity was 97% and with the addition of CH 100%. However, the specificity was only 79% through combining CH, SPT and RAST. The present study using the same standardized allergen preparation in all tests showed a good correlation between indirect test results and provocation tests.

Allergens↗

Diagnosis and immunotherapy of mould allergy. V. Clinical efficacy and side effects of immunotherapy with Cladosporium herbarum.

A placebo-controlled, double-blind study of immunotherapy with the mould species Cladosporium was performed in 22 adult asthmatics. The diagnosis of Cladosporium allergy was based on a combination of bronchial provocation test and daily symptom score in the Cladosporium season. An aqueous preparation of a potent, biologically standardized and purified extract was used in a clustered dose-increase regimen. The clinical efficacy was evaluated by a combination of symptoms (asthma score + peak flow) and consumption of antiasthmatic medication. The mean changes in symptoms and medication consumption over a 10-week registration period (peak Cladosporium season) in 1982 after 5-7 months of immunotherapy were compared with the corresponding 1981 pretreatment 10-week period. A significant (P = 0.03) difference in terms of "improved", "unchanged" and "deteriorated" patients in favour of Cladosporium treatment was found. Approximately 80% in the Cladosporium group showed improved/unchanged symptoms contrary to 30% of the placebo treated. Side effects were observed frequently but only in the Cladosporium-treated. About 70% experienced a large local reaction and 100% had episodes of asthma during dose-increase phase. Only a few severe systemic reactions occurred. Based on the clinical efficacy of the treatment we consider immunotherapy with Cladosporium feasible for highly specialized clinics.

Adolescent↗

Oral immunotherapy of children with rhinoconjunctivitis due to birch pollen allergy. A double blind study.

Thirty children with rhinoconjunctivitis due to birch pollinosis were treated in a double blind manner for 10 months with enteric-coated capsules containing either a birch pollen preparation (n = 14) with doses up to 1.4 X 10(6) biologic units per day or placebo (n = 16). Compared with the placebo group the actively treated children had less symptoms during the birch pollen season after 3 months of therapy (P = 0.035). Skin prick reactions decreased significantly more in the active group than in the placebo group after 10 months (P = 0.01). Conjunctival sensitivity was lower in the active group than in the placebo group after 3 months of treatment (P = 0.01) but not after 10 months. Compared with the placebo group the treated children more often increased their levels of IgG (P = 0.007) and pre-seasonal IgE (P = 0.001) against birch. There was a seasonal increase of IgE antibody level against birch in the placebo but not in the treatment group (P less than 0.001). None of the treated children developed asthma, compared with five of the untreated children. No general reactions occurred and few side effects were seen during the treatment period. We conclude that in children with birch pollinosis oral immunotherapy with high doses of a biologically potent preparation in enteric-coated capsules is effective, easy to perform, economic and safe.

Administration, Oral↗