Hans de Groot

Monoclonal antibodies to the major feline allergen Fel d I: I. Serologic and biologic activity of affinity-purified Fel d I and of Fel d I-depleted extract

Monoclonal antibodies were raised against a major feline allergen, Fel d I. The specificity of the antibodies for Fel d I was demonstrated by a modified crossed immunoelectrophoretic procedure. These antibodies were used in affinity purification and depletion. Fed d I was eluted from the affinity matrix at a low pH. It was tested in serologic and biologic assays. Results of both the RAST and the histamine release test with affinity-purified Fel d I confirmed that it is a very potent allergen for the majority of patients allergic to cats. In the extract depleted with the monoclonal antibody, the ratio Fel d I/cat albumin was reduced by a factor of 20. With this depleted extract, 18 of 25 patients showed a reduction greater than 50% of the bound anti-IgE in the RAST compared with the RAST with crude cat extract. In the histamine release test with cells from two patients, the activity of the depleted extract was reduced by factors of 30 and 40, respectively. Depletion of Fel d I by polyclonal antibodies resulted in a reduction of the ratio Fel d I/cat albumin by a factor of 330. In the RAST, a reduction of the IgE response greater than 50% was found in 23 of 25 patients; in 12 patients the reduction was greater than 90%. In the histamine release test, the polyclonally depleted extract was 200 to 300 times less potent than the crude cat-dander extract. These results indicate that a very large proportion of the allergenic activity of cat-dander extract is caused by a single molecule: Fel d I.

Anaphylactic reaction after the first dose of sublingual immunotherapy with grass pollen tablet

type I hypersensitivity reaction. As there are no commercial tests for specific IgE levels or validated allergy skin test for clarithromycin, clinical history associated with a drug challenge remains the most valuable diagnostic tool in such cases. In this case, the life-threatening reaction experienced by the patient precluded the use of an oral challenge to confirm her clarithromycin allergy. It is possible that the highly atopic background of the patient and especially her current asthma exacerbation might have contributed to the clinical severity of the reaction to clarithromycin. It was previously reported that severe allergic reactions to drugs including antibiotics were associated with risk factors such as asthma, atopy or other drug allergy (2). Allergic reactions to macrolides are usually described in the medical literature as case reports mainly to erythromycin and spiramycin (3). There is one case report describing a bronchospastic reaction to clarithromycin during drug challenge in a woman evaluated because of adverse drug reactions (4). Given that clarithromycin is reported to have less adverse events and better tolerability when compared with other macrolides (5) and that its use is reported to be on the increase among children in North America (6), it is crucial to increase the awareness to life-threatening allergic reactions associated with clarithromycin.

EAACI position paper on occupational rhinitis

The present document is the result of a consensus reached by a panel of experts from European and non-European countries on Occupational Rhinitis (OR), a disease of emerging relevance which has received little attention in comparison to occupational asthma. The document covers the main items of OR including epidemiology, diagnosis, management, socio-economic impact, preventive strategies and medicolegal issues. An operational definition and classification of OR tailored on that of occupational asthma, as well as a diagnostic algorithm based on steps allowing for different levels of diagnostic evidence are proposed. The needs for future research are pointed out. Key messages are issued for each item.

Immunotherapy in children and adolescents with allergic rhinoconjunctivitis: a systematic review

Allergen‐specific immunotherapy is one of the cornerstones of allergic rhinoconjunctivitis treatment. Since the development of non‐invasive administration forms with better safety profiles, there is an increasing tendency to prescribe immunotherapy in youngsters. However, no overview is available on the efficacy of immunotherapy in all its different administration forms in youngsters. Therefore, we systematically reviewed randomized controlled trials (RCTs) to evaluate the effect of immunotherapy with inhalant allergens on symptoms and medication use in children and adolescents with allergic rhinoconjunctivitis. Medline, EMBASE, the Cochrane Controlled Clinical Trials Register and reference lists of recent reviews and published trials were searched. RCTs including youngsters aged 0–18 yr with allergic rhinoconjunctivitis and comparing immunotherapy with placebo, symptomatic treatment or a different administration form of immunotherapy were included. Primary outcome measures were rhinoconjunctivitis symptom and/or medication scores. Methodological quality was assessed using the validated Delphi list. A method of best evidence synthesis, a rating system with levels of evidence based on the overall quality and the outcome of the trials, was used to assess efficacy. Six subcutaneous (SCIT), four nasal (LNIT), seven oral (OIT) and 11 sublingual (SLIT) immunotherapy trials, comprising 1619 youngsters, were included. Only 39% of the trials were of high methodological quality. For the SCIT and OIT subgroups the level of evidence for efficacy was conflicting. Moderate evidence of effect was found for LNIT. Analysis of the SLIT subgroup showed no evidence of effect. The evidence for the perennial and seasonal allergen trials within the subgroups varied from moderate evidence of effect to no evidence of effect. In conclusion, there is at present insufficient evidence that immunotherapy in any administration form has a positive effect on symptoms and/or medication use in children and adolescents with allergic rhinoconjunctivitis.

Occupational allergy caused by flowers

We describe 14 consecutive patients with complaints due to the handling of flowers. The symptoms varied from allergic rhinoconjunctivitis and asthma to urticaria. Most patients had professions in the flower industry. Skin prick tests (SPT) were performed with home‐made pollen extracts from 17 different flowers known to be the most commonly grown and sold in The Netherlands. RAST against mugwort, chrysanthemum, and solidago was performed. The diagnosis of atopy against flowers was based on work‐related symptoms due to the handling of flowers, positive SPT with flower extracts, and positive RAST The concordance between SPT and case history was 74%, and that between SPT and RAST was 77% Extensive crosssensitization was seen to pollen of several members of the Compositae family (e.g., Matricaria. chrysanthemum, solidago) and to pollen of the Amaryllidaceae family (Alstroemeria and Narcissus). Homemade flower extracts can be used to confirm IgE‐mediated flower allergy. Mugwort can be used as a screening test for possible flower allergy. For most patients, the allergy led to a change of profession.

Sublingual immunotherapy not effective in house dust mite-allergic children in primary care

To cite this article: de Bot CMA, Moed H, Berger MY, Röder E, Hop WCJ, de Groot H, de Jongste JC, van Wijk RG, Bindels PJE, van der Wouden JC. Sublingual immunotherapy not effective in house dust mite–allergic children in primary care. Pediatr Allergy Immunol 2011; Doi: 10.1111/j.1399‐3038.2011.01219.x

Birch pollinosis and atopy caused by apple, peach, and hazelnut; comparison of three extraction procedures with two apple strains

This study aimed, first, to study the prevalence in The Netherlands of atopy caused by apple, peach, and hazelnut in patients with tree pollinosis, and, second, to compare three extraction procedures for skin prick testing with two different apple strains. Skin prick tests and RAST were performed on 79 consecutive patients with tree pollinosis, visiting the department of allergology during spring 1995. In skin prick tests, we used three different extracts (juice, freeze‐dried extract, and low‐temperature acetone powder extract) of two apple strains, Golden Delicious and Granny Smith. Case histories for apple, peach, and hazelnut were positive in 35 (44.3%), 23 (29%), and 35 (44.3%) patients, respectively. More than two‐thirds of the patients had symptoms characteristic of oral allergy syndrome. Skin prick tests for apple, peach, and hazelnut were positive in 51 (64.6%), 61 (77.2%), and 71 (89.9%) patients, respectively. Granny Smith showed more positive skin reactions and a better agreement with clinical history than Golden Delicious, and juice was superior to the two other extraction procedures for both apple strains. RAST for apple, peach, and hazelnut was positive in 53 (68.8%), 13 (16.9%), and 31 (40.3%) patients, respectively. Concordance between skin prick test and case history was found in 77%, 52%, and 54%, for apple, peach, and hazelnut, respectively. We found a high percentage of concurrence of clinical allergy to birch pollen and apple, peach, and hazelnut, confirmed by both skin prick testing and RAST. Approximately half of these patients had symptoms (especially oral allergy syndrome) after eating these products. We also found an easy extraction procedure (juice extract) suitable for apple skin prick testing, superior even to freeze‐dried extraction or the low‐temperature acetone powder technique.

Prevalence of sensitization to the predatory mite Amblyseius cucumeris as a new occupational allergen in horticulture

Background: Protection against thrips, a common pest in bell pepper horticulture is effectively possible without pesticides by using the commercially available predatory mite Amblyzeius cucumeris (Ac). The prevalence of sensitization to Ac among exposed greenhouse employees and its clinical relevance was studied.

Nasal nitric oxide : longitudinal reproducibility and the effects of a nasal allergen challenge in patients with allergic rhinitis

Background:  Exhaled nitric oxide (eNO) is a validated noninvasive marker of airway inflammation in asthma. In patients with allergic rhinitis (AR), increased levels of nasal nitric oxide (nNO) have also been measured. However, the applicability of nNO as a marker of upper airway inflammation awaits validation.

Prevalence of natural rubber latex allergy (Type I and Type IV) in laboratory workers in The Netherlands

The objective of the study was to study the prevalence of Type IV and Type I allergy to natural rubber latex (NRL) in a population at risk in the Netherlands. Laboratory workers regularly using gloves were invited to complete a questionnaire and to be tested. We performed patch tests with standard contact allergens, rubber additives, glove powder and pieces of 4 gloves; prick tests with inhalant allergens, glove extracts, glove powder and fruit extracts; and RASTs. Glove‐related hand dermatitis was reported in 36.9% of the individuals interviewed. A positive patch test result for rubber additives was seen in only 6.6%. Glove‐related urticaria, rhinoconjunctivitis and/or asthma were reported in 24.6% of all cases. Confirmation of an IgE‐mediated reaction was achieved in 8.3% by prick test with glove extracts and 5.0% by RAST No reaction to glove powder was noticed in patch testing or in prick testing. A high prevalence rate of glove‐related symptoms and NRL Type I allergy was found in laboratory workers exposed to rubber gloves. Surprisingly, there was no co‐existence of Type I and Type IV allergy in this population.