Measurement of IgE antibodies against purified grass pollen allergens (Lol p 1, 2, 3 and 5) during immunotherapy.

BACKGROUND: IgE titres tend to rise early after the start of immunotherapy, followed by a decline to pre-immunotherapy levels or lower. OBJECTIVES: We were interested to know whether the early increase in IgE antibodies includes new specificities of IgE, and whether these responses persist. METHODS: Sera of 64 patients undergoing grass pollen immunotherapy were tested for IgE against four purified grass pollen allergens: Lol p 1, 2, 3, and 5. At least two serum samples were taken, one before the start of therapy and one between 5 and 18 months after the first immunization (mean: 10 months). RESULTS: The mean IgE responses to Lol p 1, 2 and 3 showed a moderate but not significant increase. In contrast, the mean IgE response to Lol p 5 showed a significant decrease of > 30%. IgE against total Lohum perenne pollen extract moderately increased (> 20%), showing that a RAST for total pollen is not always indicative for the development of IgE against its major allergens. For > 40% of the patients it was found that IgE against one or more of the four allergens increased, while IgE against the remaining allergen(s) decreased. For 10 sera the ratio of IgE titres against at least two allergens changed by at least a factor of 5. The changes in specific IgE also included conversions from negative (< 0.1 RU) to positive (0.6 to 5.0 RU) for five patients. For two patients, the induction of these 'new' IgE antibodies against major allergens was shown to result in a response that was persistent over several years. CONCLUSION: Although active induction of new IgE specificities by immunotherapy was not really proven, the observations in this study indicate that monitoring of IgE against purified (major) allergens is necessary to evaluate changes in specific IgE in a reliable way.

Allergy to pine nuts in a bird fancier.

A patient is described with the bird-egg syndrome who experienced an anaphylactic reaction after eating some of her parrot's food (pine nuts: Pinus pinea). Specific IgE against this nut and another pine nut (P. cembra) was demonstrated by RAST. Cross-reactivity between these botanically related seeds was shown by RAST inhibition. Besides avian antigens, bird food antigens should be taken into consideration when symptoms of allergy occur on exposure to birds.

Food-induced contact urticaria syndrome (CUS) in atopic dermatitis: reproducibility of repeated and duplicate testing with a skin provocation test, the skin application food test (SAFT).

IgE-mediated contact urticaria syndrome (CUS) is one of the manifestations of allergy in childhood atopic dermatitis (AD). Allergens such as foods and animal products penetrate the skin easily. They can then cause urticarial reactions in sensitized individuals. A provocation test system for foods, called the skin application food test (SAFT), has been developed. Over more than 5 years, a group of 175 patients with AD was built-up and investigated in a prospective follow-up study with SAFT. SAFT was more frequently positive in AD children aged 0-2 years than in older children. In several children of this population (Group 1), we repeated SAFT within a period of 1 year. In another unrelated group of children (Group 2-1), we compared the results of 'original' SAFT and SAFT using square chambers (Van der Bend) or Silver patches. In the 3rd group (Group 2-2) we compared 'original' SAFT with SAFT using big Finn Chambers. The agreement between the tests was high: in Group 1, we observed 88 to 93% concordant scores, and in Group 2, the scores were 96% to 100%. Statistically, the kappa coefficient ranged from 0.71-0.87 in Group 1, and from 0.83-1.00 in Group 2. SAFT is therefore highly reproducible. Agreement was at least > or = 88% between the scores (the lowest kappa value observed was at least 0.71).

Immediate- and delayed-type contact hypersensitivity in children older than 5 years with atopic dermatitis: a pilot study comparing different tests.

We conducted a prospective open study of immediate- and delayed-type contact hypersensitivity to food and other allergens in 33 children with atopic dermatitis (AD). The design of the study was exploratory and not randomized. Various methods for detecting immediate-type hypersensitivity were compared. Thirty-three children age 5 to 15 years with persistent AD were initially enrolled, but 3 dropped out. Nine patients had positive reactions to foods in the patch-scratch test, four had positive reactions in the skin application food test, and five had positive reactions to foods in the prick tests. Positive reactions to foods were observed in only three patients on the delayed-type patch tests. In all tests, but especially the patch-scratch and prick tests, positive reactions to food allergens were observed without clinically related symptoms. None of these tests gave ideal results. Twenty (67%) of the 30 children had positive reactions to inhalants in prick testing. Fourteen showed positive patch-test reactions with the European standard series (True Test). The most positive reactions were to nickel (9 patients), cobalt, and balsam of Peru. Restrictive measures led to evident improvement of AD only in some children. The results of this study illustrate that food allergy plays only a limited role in patients with AD age 5 to 15 years. We could not conclude which of the tests would predict which children might benefit from dietary manipulation.

Nasal reactivity to histamine and methacholine: two different forms of upper airway responsiveness.

In 44 subjects (healthy controls and patients with allergic, non-allergic or infectious rhinitis) we compared nasal histamine and methacholine responsiveness. A weak correlation between histamine- and methacholine-induced secretion was found (r = 0.34; p = 0.02), in contrast to the highly significant association between secretion and sneezes induced by histamine (r = 0.78; p < 0.0001). Our observations suggest that histamine and methacholine responsiveness represent different forms of upper airway hyperreactivity. The contribution of glandular responsiveness as measured by methacholine challenge and the involvement of irritant receptors or reflexes as measured by histamine provocation may vary between individuals.

Nasal hyperreactivity and its effect on early and late sequelae of nasal challenge with house-dust mite extract.

For a study on the relationship between nasal hyperreactivity to histamine and the nasal response to allergen, 14 rhinitis patients allergic to house-dust mites were challenged with histamine and 5 days later with a house-dust mite (HDM) extract. According to symptom scores, after allergen challenge two groups of patients were distinguished, i.e., isolated early and dual responders. The nasal response to histamine was significantly correlated with the amount of secretion (r = 0.71; p = 0.0039) and the number of sneezes (r = 0.78; p = 0.0016) induced by the HDM extract during the early reaction. The amount of allergen-induced secretion could be predicted from the response to histamine, skin reactivity to allergen, and blood eosinophils (multiple r = 0.90; p < 0.0001). Late-phase symptoms appearing between 3.5 and 9.5 hour after allergen challenge could be predicted from histamine responsiveness and skin reactivity (multiple r = 0.67; p = 0.004). Compared with early responders (LAR-) (n = 8), patients with early and late symptoms (LAR+) (n = 6) were characterized by a higher secretory responsiveness to histamine (p = 0.033), increased production of leukotrienes determined in nasal lavage fluid during the early response (p = 0.033), and elevated albumin levels occurring between 3.5 and 9.5 hours after challenge (p = 0.043). Late-phase symptoms were significantly correlated with albumin influx (r = 0.73; p = 0.001) and leukotrienes production (r = 0.60; p = 0.011) during the early reaction. In summary, nasal responsiveness to HDM extract was found to be closely associated with pre-existent nasal hyperreactivity.(ABSTRACT TRUNCATED AT 250 WORDS)

Isolated early response after nasal allergen challenge is sufficient to induce nasal hyperreactivity.

Ten rhinitic patients allergic to grass pollen were challenged with histamine intranasally 24 hours before and 24 hours after nasal provocation with grass pollen. Up to ten hours after allergen provocation nasal lavage fluid was obtained to characterize early and late phase reactions by measuring the levels of histamine and leukotrienes as indicators of mediator release, and albumin as a marker of increased vasopermeability. Ten minutes after allergen challenge with 10,000 BU grass pollen extract LTC4,D4, and albumin significantly increased from 62 to 576 pg/mL (P = .008) and from 15 to 81 micrograms/mL (P = .008), respectively, without significant changes after placebo challenge a week earlier. Although the patients showed increased responsiveness to histamine after allergen challenge compared with a placebo-challenged control group (P = .02), one patient only demonstrated a late phase nasal allergic reaction characterized by recurrence of clinical symptoms eight to ten hours after allergen challenge and recurrence of mediators in lavage fluid. It is concluded that an isolated early response after allergen challenge is sufficient to induce nasal hyperreactivity. A biochemically or clinically defined late phase allergic reaction does not necessarily accompany allergen-induced hyperreactivity.

Food immediate-contact hypersensitivity (FICH) and elimination diet in young children with atopic dermatitis. Preliminary results in 107 children.

In atopic dermatitis [AD], not only food consumption, but direct skin-contact too can provoke hypersensitivity reactions. We imitated food immediate-contact hypersensitivity [FICH] to cow's milk, egg, peanut or soy by a skin provocation test. This skin application food test [SAFT] was applied in 91 patients aged up to 5 years and suffering from AD, and in 16 healthy controls (all SAFT-negative). In the SAFT-positive patients (n = 61), FICH to egg was observed in 72%, to cow's milk in 47%, to peanut in 34% and soy in only 1 patient. SAFT and RAST scores correlated weakly. Nevertheless, many discrepancies between SAFT and RAST results were found. In 20 of the 61 (33%) patients with FICH, a flare-up in AD was noted at SAFT testing. Upon introducing dietary restrictions, AD improved impressively in 9 of 23 patients who could be followed up. FICH is an important symptom in children with AD and food allergy.

[Exercise-dependent anaphylaxis]. / Inspanningsafhankelijke anafylaxie.

The clinical features of exercise-induced anaphylaxis in 5 patients are described, with an accurate history, skin tests, IgE determinations and exercise tests. In these 5 patients we were able to distinguish three different forms of exercise-induced disease: exercise-induced anaphylaxis based upon an IgE-mediated allergy to foods, exercise-induced anaphylaxis without food allergy and cholinergic urticaria.

Nasal hyper-responsiveness to histamine, methacholine and phentolamine in patients with perennial non-allergic rhinitis and in patients with infectious rhinitis.

Recently it has been shown that patients with atopic rhinitis and with an allergy to house dust mites have a stronger nasal response to insufflation of histamine, methacholine and phentolamine than a control group. This hyper-responsiveness could not be demonstrated in patients with perennial non-allergic rhinitis, unless the patients were selected according to the predominant symptoms in the history. Patients with rhinorrhoea ('runners') proved to be hyper-responsive to methacholine compared with normal controls. The existence of two subpopulations was emphasized by hyper-responsiveness to both histamine and methacholine in the runners group compared with the patients with a stuffy nose ('blockers'). Patients with chronic nasal infections (characterized by recurrent episodes of purulent discharge) showed no hyper-responsiveness at all, indicating that either hyper-reactivity does not play an important part in this patient population or methods to detect hyper-reactivity in this group are inadequate. In contrast to our earlier observations in patients with atopic rhinitis, increased responsiveness to phentolamine could not be detected either in the patients with perennial rhinitis or in the patients with infectious rhinitis, indicating that the possible alpha-adrenergic dysfunction found in patients with atopic rhinitis is restricted to this group.

Occupational allergy to pancreatic powder: characterization of IgE-binding antigens in pancreatic extract by immunoblotting.

The IgE response to inhaled dust of pancreatic powder was studied with sera from two employees of a pharmacy. IgE from both sera was directed against both porcine and bovine trypsin preparations. The major IgE-binding structures had an isoelectric point in the pH 8 to 9 range. The molecular weight of the IgE-binding structures was different for both patients. In one patient, most IgE was directed against a 28 to 30 kd structure, whereas the second patient had IgE directed against components with a molecular weight of 35 and 45 kd, respectively.

Phazet skin prick tests versus conventional prick tests with allergens and histamine in children.

Forty children underwent two different skin prick tests with allergen-coated Phazet needles and conventional skin prick tests using Pharmalgen extracts (100,000 BU/mL). Good correlation between both skin test methods was found with house dust mites (Rs = 0.61; P less than .001), timothy pollen (Rs = 0.77; P less than .001), and cat epithelium (Rs = 0.74, P less than .001). The correlation coefficient in the case of histamine was lower (Rs = 0.50; P less than .01) than that obtained from the allergens. Larger wheals were generated with Phazet than with conventional prick tests (median: 54.5 mm2 and 24.5 mm2, respectively; Wilcoxon signed rank test, P less than .0001). Comparison of wheal areas and specific IgE did not reveal large differences between the two skin test methods. In conclusion, Phazet, a recently introduced simple, standardized, skin prick test method can replace the conventional skin prick test for the most important allergens such as house dust mites, timothy pollen, and cat epithelium.

[Occupational pollinosis in gardeners]. / Beroepspollinose bij tuinders.

The symptoms of occupational pollinosis are described on the basis of case histories, skin tests and serological tests of six commercial gardeners. Exposure to gerberas, freesias, chrysanthemums and to genera of the nightshade family (Solanaceae) such as paprikas, tomatoes, egg plants and potatoes may lead to allergy with raised IgE levels.

Nasal provocation with histamine in allergic rhinitis patients: clinical significance and reproducibility.

In a selected group of rhinitis patients (n = 12) with an IgE-mediated allergy to house dust mites, the nasal response to insufflation of histamine chloride appeared to be related to symptom scores obtained from the patients. In contrast to the sum of the nasal airway resistances (NAR) induced by all doses of histamine, the total amount of secretion and total number of sneezes could be predicted from clinical scores. The reproducibility of the nasal provocation test was tested by comparison of the test results in two sessions with a 1-week interval. The correlation between both sessions was highest with respect to nasal secretion (r = 0.87; P less than 0.001) and the number of sneezes (r = 0.76; P = 0.004). The correlation coefficient was 0.71 (P = 0.01) when the nasal airway resistance was used in the assessment of nasal response. A good reproducibility of the nasal provocation test was also obtained using an end-point titration method and determining the concentration required to produce 0.5 ml secretion and/or five sneezes as the end-point (r = 0.76; P = 0.004). The concentration required to double nasal airway resistance yielded a correlation coefficient of 0.56 (P = 0.052). We conclude that the clinical significance of nasal provocation with histamine increases when, besides nasal airway resistance, the amount of secretion and the number of sneezes is used in the assessment of the nasal response.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunoblot analysis of IgE-binding antigens in spices.

The IgE response to coriander and other spices was studied by immunoblotting, after separation of the spice extracts by isoelectric focusing and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). A major IgE-binding component from coriander had an isoelectric point of pH5. After incubation of SDS-PAGE-separated spice extracts with serum from a patient with an occupational allergy to spices, a closely related pattern of IgE binding to coriander, dill and anise extract was observed. These results suggest that the botanically related spices, coriander, anise and dill, contain common IgE-binding structures.