Comparison of skin prick tests with specific serum immunoglobulin E in the diagnosis of fungal sensitization in patients with severe asthma

Background It has been shown that patients with allergic bronchopulmonary aspergillosis (ABPA) and patients with severe asthma with fungal sensitization (SAFS) can benefit from antifungal therapy. It is not known whether allergy skin prick tests (SPT) or specific IgE tests are more sensitive in the identification of patients who are sensitized to fungi and who are therefore candidates for antifungal therapy.
Objectives To compare SPT and specific serum IgE tests for fungal sensitization in patients with severe asthma.
Methods We have undertaken SPT and specific serum IgE tests to six fungi ( Aspergillus fumigatus, Candida albicans, Penicillium notatum, Cladosporium herbarum, Alternaria alternata and Botrytis cineria ) and specific serum IgE test for Trichophyton in 121 patients with severe asthma (British Thoracic Society/SIGN steps 4 and 5).
Results Sixty-six percent of patients were sensitized to one or more fungi based on SPT and/or specific serum IgE results. Positivity to SPT and/or specific serum IgE was as follows: A. fumigatus 45%, C. albicans 36%, P. notatum 29%, C. herbarum 24%, A. alternata 22%, B. cineria 18%, Trichophyton 17% (specific serum IgE only). Concordance between the tests was 77% overall but only 14–56% for individual fungi. Twenty-nine (24%) patients were sensitized to a single fungus and seven (6%) were sensitized to all seven fungal species. Fifty percent of patients were sensitized to fungal and non-fungal extracts, 21% were sensitized only to non-fungal extracts, 16% were sensitized only to fungal extracts and 13% had no positive tests.
Conclusion This study is consistent with previous reports that fungal sensitization is common in patients with severe asthma. At present, it remains necessary to undertake both SPT and specific serum IgE testing to identify all cases of fungal sensitization. This may be important in the identification of patients with ABPA and SAFS who may benefit from antifungal therapy.     

Sensitization to fungi: epidemiology, comparative skin tests, and IgE reactivity of fungal extracts

BACKGROUND: Several fungal species are known to cause severe respiratory and cutaneous allergic diseases. Extracts from several allergenic fungi are used for in vivo and in vitro tests, as standard preparations are still not available. OBJECTIVE: The aims are to define the pattern of in vivo and in vitro IgE reactivity to fungal species in an allergic population with respiratory symptoms; to determine the influence of different extract preparations on diagnostic results; and to evaluate whether there exists a relationship between the diagnostic pattern of reactivity and the pattern of specific IgE reactivity in immunoblots. METHODS: Skin prick tests were applied to a cohort of 4962 respiratory subjects, aged 3-80 years. Fungal extracts from Alternaria, Aspergillus, Candida, Cladosporium, Penicillium, Saccharomyces, and Trichophyton were used, along with extracts from pollens, mites, and animal dander. Demographical and diagnostic data were recorded. IgE detection was carried out with the same allergenic extracts plus Malassezia. Comparative skin tests and IgE detection were carried out using extracts from three commercial suppliers. IgE immunoblots were carried out with the same panel of commercial fungal extracts and were compared with in-house extracts. Data analysis was carried out by grouping the population on the basis of their reactivity to a single, to two or to more than two, mould species. RESULTS: Nineteen percent of the allergic population reacted to at least one fungal extract by means of the skin test. Alternaria and Candida accounted for the largest number of positive tests, and along with Trichophyton they were the main sensitizers in the subset of patients with an isolated sensitization. The prevalence of skin test reactivity increased for these three fungi in the subsets with two associated reactivities and, furthermore, in the subset showing reactivity to more than two mould species. In the latter group, a steady increase of the skin test reactivity was recorded for all the other fungal sources, suggesting a clustered reactivity. Comparative skin and IgE testing with different groups of subjects with a simple pattern of skin reactivity resulted in sensitivity differences between in vivo and in vitro tests, whereas discrepant results were recorded in the subsets of patients with multiple fungi sensitization. Although hampered by the limited reliability of fungal extracts, IgE immunoblots revealed differing patterns of reactivity when sera from the three subsets were used. This suggests a link between the diagnostic reactivity pattern and the IgE sensitization to extracts' components. Age and gender distribution differed among the Alternaria-, Candida-, and Trichophyton-sensitized subjects, but not in the subset with more than two fungi sensitizations. CONCLUSIONS: The preliminary assessment of a new classification of the mould-sensitized population has been reached. The limiting quality of fungal extracts requires future studies using an allergenic molecule-based approach. The diagnostic process and the definition of the reactivity pattern would thus be easy, and it could lead to a novel specific immunotherapy approach.     

Immedeate and delayed-type reactivity to fungi and effects of antifungal drugs on atopic dermatitis]

OBJECTIVE: To investigate immediate and delayed-type reactivity for fungi in atopic dermatitis (AD) patients and the effect of antifungal therapy. METHODS: We examined immediate and delayed-type reactivity in AD patients for Candida albicans and Malassezia furfur by skin prick test (SPT), and estimated the effect of amphotericin B (AMPH) and itraconazole (ITCZ). RESULTS: Twenty eight of 40 patients showed positive immediate-type reaction and 10 of 27 patients did delayed-type reaction for Candida albicans. As for Malassezia furfur, positive immediate-type reaction was shown in 30 of 40 patients and positive delayed-type reaction did in 4 of 27 patients. The RAST score of specific IgE to Candida albicans was low in the patients with positive delayed-type skin reaction for Candida albicans, while the score was high in the patients with the negative delayed-type skin reaction. Both of AMPH and ITCZ were effective to the patients with positive immediate-type reaction for Candida albicans in SPT. The skin reaction for Malassezia furfur was stronger in the patients treated with ITCZ effectively than in the patients treated not effectively. In addition, ITCZ was effective in all patients except one, who showed positive reaction for Malassezia furfur accompanied with negative reaction for Candida albicans in SPT. CONCLUSION: Fungal allergy is one of the aggravation factors of AD, and SPT is useful to evaluate fungal allergy and to choose effective antifungal therapy.     

Fungi and atopic dermatitis]

Attention has recently been centered on fungi as aggravating factors of atopic dermatitis (AD) due to the frequent detection of IgE antibodies to fungi in patients with severe AD and to positive response of some cases of AD to antifungal therapy. Malassezia sp.: In AD patients with prominent symptoms in the head and neck, areas prone to colonization by Malassezia, the titers of specific anti-Malassezia IgE antibodies are high, which positively correlate with the total IgE value and the severity of AD. The patch test against Malassezia antigens is positive. The rate of isolation of Malassezia from the skin of AD patients is higher than that from the skin of healthy control subjects. Candida sp.: In patients with severe AD, the rate of positive skin prick tests for Candida is high, and a correlation exists between positive skin prick test results and the presence of Candida albicans in nasopharynx. However, the reactivity to Candida antigens in the patch tests is reduced, and a negative correlation is seen. There is no difference between the isolation rate of C. albicans from patients with adult-type AD and normal controls. However, AD patients give a significantly greater number of separate colonies. The range of efficacy rate of antifungal therapy of AD is reported to be 50-65 %. The efficacy rate of our own trial falls within this range. Following treatment, the rate of isolation of fungi decrease significantly, and the titers of specific antifungal IgE antibodies are not statistically significant. The clearance of fungi from the tissue following antifungal therapy probably results in the suppression of direct or indirect inflammatory reaction caused by the fungi. We therefore consider antifungal therapy as one of the second-line therapies to be administered in AD cases resistant to conventional basic therapy.     

Cladosporium herbarum and Pityrosporum ovale allergen extracts share cross-reacting glycoproteins

BACKGROUND: Patients sensitized to airborne fungi such as Alternaria alternata and Cladosporium herbarum often also show positive skin prick test results and specific serum IgE antibodies to a yeast, Pityrosporum ovale. We examined whether part of the IgE binding to these fungi is explained by cross-reacting mould and yeast allergens. METHODS: Serum samples from 36 patients with positive skin prick test to A. alternata or C. herbarum were analyzed for IgE antibodies to fungal extracts by ELISA and immunoblot analysis. Cross-reactivity between mould and yeast extracts was studied by ELISA and immunoblot inhibition assays. In further analysis, the mannan-containing glycoproteins were removed from the yeast extract by concanavalin A-Sepharose chromatography, and the IgE binding properties of the extracts were compared. RESULTS: Serum IgE reactivity to P. ovale was found in 40% of the mould-sensitized patients. The IgE antibody binding to A. alternata and C. herbarum moulds was partially inhibited by the yeast P. ovale in ELISA and immunoblot inhibition assays. When the glycoproteins were removed from the extract, cross-reactivity was markedly reduced. CONCLUSION: Part of the IgE binding to mould and yeast allergen extracts is due to cross-reacting glycoproteins. False-positive IgE and skin prick test results should be taken into account in the diagnosis of mould allergy.     

Relationship of immediate and delayed hypersensitivity to nasopharyngeal and intestinal growth of Candida albicans in allergic subjects

The growth of C. albicans yeast in the nasopharynx and in the anus as well as allergy symptoms were followed up for 8 months in 67 patients with bronchial asthma, allergic rhinitis and/or atopic eczema. 38 of the patients were skin prick test positive and 29 negative to C. albicans allergen extract. 32 of the patients had positive and 19 negative delayed skin reactions. The nasal, bronchial and skin symptoms of the yeast-sensitive allergic patients were not associated with the nasopharyngeal nor anal occurrence of C. albicans or other yeasts. The use of nasal or inhaled steroids had no effect on the occurrence of Candida in the nasopharynx. It was observed that immediate skin sensitivity had a positive correlation and the delayed sensitivity a negative correlation with the occurrence of C. albicans growth in nasopharynx and anus. These findings are in agreement with the concept that impaired cell-mediated immunity to C. albicans may lead to increased IgE response. This may explain the increased liability towards C. albicans nasopharyngeal and gastrointestinal "saprophytic" growth.     

IgE-mediated allergy to fungal allergens in Finland with special reference to Alternaria alternata and Cladosporium herbarum.

BACKGROUND: Alternaria alternata and Cladosporium herbarum are common fungi in outdoor environments, but their clinical significance has not been elucidated in Finland. OBJECTIVE: To evaluate the prevalence of IgE-mediated allergy and clinical outcomes caused by sensitization to fungal allergens in patients with suspected allergy. METHODS: Skin prick tests (SPTs) were performed with C. herbarum in 6,376 patients and also with A. alternata in 1,504 of these patients. SPTs were repeated in 40 patients who showed a positive reaction to either allergen using commercial and in-house extracts. The association of SPT with allergen-specific IgE antibodies in serum was evaluated. Seven patients also underwent a conjunctival challenge test with these fungal allergens. RESULTS: The prevalence of positive SPT results to A. alternata and C. herbarum was low (2.8% and 2.7%, respectively). Among the 40 patients, atopic eczema/dermatitis syndrome was found in 58%, asthma in 44%, and rhinitis in 31%. Most of the patients displayed SPT reactions also to several other fungal allergens, and 75% to 80% showed a positive SPT reaction to allergens of pet animals or pollens. Four patients had a positive reaction to A. alternata and 6 to C. herbarum in the conjunctival challenge test. CONCLUSION: In the Finnish population with allergic symptoms, IgE-mediated sensitization to 2 common fungal allergens was rare and of minor clinical importance. SPT reactions to fungi are mostly observed in patients with multiple sensitivity to various allergens.     

Atopic eczema: role of microorganisms on the skin surface

The pathophysiology of atopic eczema (AE) is still poorly understood. One possible concept favors IgE-mediated reactivity towards allergens that enter the skin from the outside or through the blood. Microorganisms of the cutaneous flora also might represent a stimulus for allergic skin reactions. Abnormal bacterial skin colonization is a characteristic feature of AE. Staphylococcus aureus (S. aureus ) is the most common pathogen. Binding to host cells involves special receptors, such as fibronectin or laminin. Specific IgE antibodies to S. aureus can be detected in the blood. Whereas the clinical relevance of anti-staphylococcal antibodies is still controversial, specific IgE antibodies to Pityrosporum species as well as positive type I prick test reactions to these yeasts seem to correlate with the intensity of eczematous lesions in the head and neck regions of patients with AE. Both antimicrobial and antifungal treatment has been shown helpful in some cases of AE.     

Analysis of the sensitization profile towards allergens in central Africa

BACKGROUND: Almost no information is available regarding the prevalence of IgE-mediated allergies and the disease-eliciting allergens in tropical Africa. OBJECTIVE: To study IgE-mediated allergies and the allergen profile in allergic patients from Zimbabwe. METHODS: The frequency of sensitization to common environmental allergen sources was determined by skin prick testing in 650 allergic patients from Zimbabwe. Fifty representative sera were analysed for IgE reactivity to 20 respiratory and 20 food allergen extracts by multiallergen extract testing. The IgE reactivity profiles to recombinant pollen and mite allergens were compared between grass pollen- and mite-sensitized patients from Zimbabwe and central Europe. Sera from grass pollen-allergic patients were also analysed for IgE reactivity to nitrocellulose-blotted natural timothy grass and Bermuda grass pollen allergens. RESULTS: IgE-mediated allergies were found to be common in Zimbabwe. Similar to the situation in central Europe, mites and grass pollens represented the most prevalent allergen sources. However, the IgE reactivity profiles determined with single recombinant pollen and mite allergens revealed interesting differences between the European and African patients, which most likely reflect the local allergen exposure. CONCLUSIONS: The striking differences regarding sensitization to grass pollen and mite allergens between African and European patients revealed by recombinant allergen-based testing emphasize the need for component-resolved allergy testing to optimize allergy prevention and therapy in different populations.     

Buckwheat pillow-induced asthma and allergic rhinitis.

BACKGROUND: Immunoglobulin (Ig)E-mediated hypersensitivity is a mechanism suggested to explain adverse reactions to buckwheat. This is the first reported case in the United States of a person who developed asthma and worsening allergic rhinitis after exposure to a buckwheat pillow. OBJECTIVE: To describe a patient who developed asthma and worsening allergic rhinitis after exposure to a buckwheat pillow and to provide evidence that the adverse reaction was IgE-mediated. METHODS: The patient underwent skin prick and ImmunoCAP testing (Pharmacia Diagnostics, Kalamazoo, MI) to buckwheat as well as skin prick testing to several environmental allergens. RESULTS: The patient showed a 4+ skin prick test response to buckwheat. He also showed 4+ positive skin prick responses to multiple trees, grasses, and weeds, Alternaria, Helminthosporium, dog, and histamine control and was 3+ positive to house-dust mites, Penicillium, Aspergillus, cat, and feather mix. His negative control was negative. His ImmunoCAP test for buckwheat-specific IgE was class 4, or strongly positive. He had normal spirometry values. Performance of house-dust mite avoidance measures did not result in improvement of the patient's symptoms. Removal of the patient's two buckwheat pillows resulted in resolution of his asthma and improvement of rhinitis symptoms. CONCLUSIONS: The positive skin prick and ImmunoCAP test to buckwheat along with the positive clinical response to buckwheat pillow elimination support an IgE-mediated mechanism in explaining our patient's buckwheat pillow-induced asthma and allergic rhinitis.     

Skin reactivity and specific IgE antibody to two nonbiting midges in Korean respiratory allergy patients.

To evaluate the significance of chironomid as a respiratory allergen, we performed skin prick tests with Chironomus plumosus (CP) and Tokunagayusurika akamusi (TA) extracts on 475 respiratory allergy patients, and their specific IgE antibodies were detected by enzyme-linked immunosorbent assay (ELISA) in 106 positive reactors to skin prick test and 30 negative controls. Ninety-seven (20.4%) showed more than 2+ of allergen to histamine ratio to CP and 98 (20.6%) to TA on skin prick test. Seventy-one (73.2%) of 97 positive reactors had increased specific IgE to CP, and 34 (34.7%) of 98 positive reactors, to TA. CP-specific IgE was detected in 14 (14.4%) non-atopic asthmatics and 6 (6.2%) non-allergic rhinitis patients. TA-specific IgE was detected in 17 (17.4%) non-atopic asthmatics and 6 (6.1%) non-allergic rhinitis patients. No association was noted between skin reactivity to Dermatophagoides farinae and the prevalence of specific IgE to CP or TA (p > 0.05). The correlation between total IgE level and specific IgE level to CP and TA was poor (r = 0.07, 0.04). ELISA inhibition test suggested specificity of IgE binding and cross-allergenicity between CP and TA. It is suggested that CP and TA can induce IgE-mediated reaction in exposed patients and should be considered as important causative allergens in respiratory allergy patients in Korea.     

Sensitization to local dust-mite fauna in Singapore

BACKGROUND: Recent studies showed the presence of a unique dust-mite fauna in the indoor environment of Singapore. Immediate hypersensitivity to these dust mites, along with other known indoor allergens, may play a role in the pathogenesis of allergic respiratory diseases. This study evaluated the sensitization rates of the local atopic population to these allergens. METHODS: The skin prick test was performed on a total of 391 individuals (289 patients with asthma and/or allergic rhinitis and 102 healthy controls) using extracts of six species of local dust mites (Austroglycyphagus malaysiensis, Blomia tropicalis, Dermatophagoides pteronyssinus, D. farinae, Sturnophagoides brasiliensis, and Tyrophagus putrescentiae) and 10 other common indoor allergens. Total serum IgE and specific IgE to these dust mites were also quantified with the fluorescence allergosorbent test (FAST). RESULTS: The sensitization rates among patients with asthma and/or allergic rhinitis to dust mites and other inhalant allergens tested (via skin prick tests) were as follow: B. tropicalis (96.2%), D. pteronyssinus (93.4%), D. farinae (92.3%), A. malaysiensis (78.2%), S. brasiliensis (71.6%), T. putrescentiae (71.3%), canary feathers (69.9%), Periplaneta americana (cockroach) (59.5%), Blattella germanica (cockroach) (56.4%), mosquito (Aedes sp.) (46.4%), dog epithelia (mixed breed) (34.3%), kapok seed (31.8%), cat hair (29.1%), Aspergillus fumigatus (20.8%), Penicillium notatum (18.0%), and Candida (Monilia) albicans (9.3%). All patients were observed to react to at least three of the six dust-mite extracts, with 254/289 (87.9%) reacting to at least five or to all six. Skin prick responses to the dust mites were found to correlate with the corresponding specific IgE levels quantified by FAST (P<0.001). In addition, specific IgE levels to D. pteronyssinus and D. farinae were highly correlated (Spearman's rank coefficient = 0.76, P<0.001), as were those to B. tropicalis and A. malaysiensis (r = 0.60, P<0.001). CONCLUSIONS: Asthma and/or allergic rhinitis patients were highly sensitized to the local dust-mite fauna. Thus, these dust mites should be considered important allergenic sources of this region.     

IgE-mediated and T cell-mediated autoimmunity against manganese superoxide dismutase in atopic dermatitis

BACKGROUND: Autoreactivity of patients with atopic dermatitis (AD) to human proteins has been postulated as a decisive pathogenetic factor for AD. OBJECTIVE: In this study, it was investigated whether the stress-inducible enzyme manganese superoxide dismutase (MnSOD) of human and fungal origin might act as an autoallergen in atopic dermatitis. METHODS: Patients with AD (n = 69; mean SCORAD [SCORing Atopic Dermatitis], 27) and other inflammatory skin diseases as well as with inhalant allergies were investigated. The presence of specific IgE against recombinant MnSOD of fungal and human origin and the fungal extracts of Aspergillus fumigatus and Malassezia sympodialis was measured by CAP, ELISA, skin prick test, and in subset of patients also by atopy patch tests (APTs) and PBMC proliferation assays. Cross-reactivity between allergens was determined by CAP inhibition. The presence of MnSOD in human skin in various inflammatory skin conditions was investigated by immunohistochemistry. RESULTS: Specific IgE antibodies against human MnSOD correlating with the disease activity were found in 29 out of 67 patients with AD. The human protein was able to induce in vitro T-cell reactivity and eczematous reactions in APT in MnSOD-sensitized patients with AD. MnSOD was upregulated in various inflammatory skin reactions and APT skin specimens. Cosensitization to structurally related and cross-reacting fungal MnSOD and the skin-colonizing yeast M sympodialis was observed in all patients sensitized against human MnSOD. CONCLUSION: Human MnSOD may play a role as an autoallergen in a subset of patients with AD, including nonatopic eczema. By molecular mimicry leading to cross-reactivity such sensitization might be induced primarily by exposure to environmental fungal MnSOD of M sympodialis .     

Bronchial allergen challenge in subjects with low levels of allergic sensitization to indoor allergens

BACKGROUND: Low skin reactivity to common inhalant allergens is frequently found in asymptomatic individuals as well as in patients with respiratory complaints. However, most studies on bronchial allergen challenge concern patients with high levels of allergic sensitization. The present study was directed to bronchial reactions after allergen challenge in subjects with low skin reactivity to Dermatophagoides pteronyssinus or cat dander. METHODS: Titrated intracutaneous skin tests, skin prick tests, specific IgE assays, histamine release on washed leukocytes, and bronchial histamine and allergen-challenge tests were performed in 20 subjects with an intracutaneous skin test threshold for cat dander (Felis domesticus) or D. pteronyssinus above 0.1 BU/ml (mean wheal diameter in skin prick test with 10000 BU/ml: 4.4mm). Ten of the 20 patients had specific IgE below the detection limit in at least one of the three IgE assays which were done. Fifteen patients had a specific IgE level below 2 kU/I in all three tests. As a positive control group, the same parameters were studied in seven moderately sensitized patients with an intracutaneous skin test threshold below 0.1 BU/ml (mean wheal diameter with 10000 BU/ml: 7.2mm). RESULTS: The 20 subjects with low levels of allergic sensitization had an early decrease in FEV1 of 8.6% (P<0.01) and a mean late decrease of 6.3% (P<0.05). There was a trend for decrease in PC20 histamine 24h after allergen challenge (-0.4 doubling doses, P=0.09). CONCLUSIONS: In this group of subjects with low levels of allergic sensitization, a statistically significant early and late decrease in FEV1 was found. However, the decrease in lung function was small and unnoticed by most patients. The increase in nonspecific bronchial hyperresponsiveness after bronchial allergen challenge did not reach statistical significance in the study group. The results indicate that allergen exposure in patients with low levels of allergic sensitization may lead to airways changes in the absence of acute symptoms.     

Diversity of asparagus allergy: clinical and immunological features

BACKGROUND: Asparagus (Asparagus officinalis) is an extensively grown and consumed vegetable. To a lesser extent than other Liliaceae vegetables, allergic contact dermatitis (ACD) due to asparagus has been reported. However, only a few case reports of asparagus IgE-mediated allergy have been published. In a previous study, we demonstrated that two lipid transfer proteins (LTPs) (Aspa o 1.01 and Aspa o 1.02) were relevant allergens of asparagus. OBJECTIVE: We retrospectively analysed the 27 patients diagnosed with asparagus allergy during the last 5 years. All of them reported adverse symptoms after either asparagus ingestion or handling. We describe their clinical features and evaluate whether they were associated to immunological findings (immunoblot pattern and skin reactivity to LTPs). METHODS: Patients underwent skin prick and patch tests with standard panels of vegetables and aeroallergens. Besides crude asparagus extract, two purified LTPs were prick and patch tested. Total and specific IgE measurements and asparagus extract IgE immunoblotting were performed. Patients reporting asthma symptoms underwent specific inhalation challenge to asparagus. RESULTS: Of the 27 subjects, eight had ACD, 17 had IgE-mediated allergy and two had both ACD- and IgE-mediated allergy. Positive patch tests with the crude asparagus extract but not with LTPs were observed in subjects with ACD (n=10). Of 19 patients with IgE-mediated disease, 10 had contact urticaria after asparagus handling. Of them, five subjects and five others without skin allergy showed respiratory symptoms; of them, eight were diagnosed with occupational asthma confirmed by positive asparagus inhalation challenge, whereas the remaining two had isolated rhinitis. Four patients suffered from immediate allergic reactions related to asparagus ingestion (food allergy); three of them reported anaphylaxis whereas the other had oral allergic syndrome. Positive IgE immunoblotting (bands of 15 and 45-70 kDa) was observed in 10 subjects. Of 10 subjects with positive prick test to LTPs, six showed bands at 15 kDa. Either IgE-binding bands or positive prick tests to LTPs were observed in asthma (62%) and anaphylaxis (67%). CONCLUSION: Asparagus is a relevant source of occupational allergy inducing ACD and also IgE-mediated reactions. Severe disease (anaphylaxis or asthma) is common and LTPs seem to play a major role. The clinical relevance of LTP sensitization among patients with mild disease or symptom-free subjects should be addressed in prospective studies.     

Allergic hypersensitivity to the lentil pest Bruchus lentis

BACKGROUND: Lentils are the most common legume involved in allergic reactions in the Mediterranean area and India. Lentil crops could be attacked by a wide range of insect species. Occupational asthma caused by the lentil pest Bruchus lentis has been described in the present study. OBJECTIVE: We studied the possibility of immunoglobulin (Ig)E-mediated hypersensitivity to lentil pests in 16 patients who suffered from allergic symptoms (asthma and anaphylaxis) related to inhalation of lentil particles or ingestion of lentils, in which sensitization to legume proteins was not clear. METHODS: Extracts prepared either from noninfested and infested lentils, and from the lentil parasite B. lentis were used for skin prick testing (SPT), bronchial and oral challenges and in vitro determinations. RESULTS: Skin prick test were positive to infested lentils and B. lentis in all patients and negative to noninfested lentil extracts. Five asthmatic patients reacted in the bronchial challenge test with Bruchus extract. Oral challenges performed with boiled infested lentils were positive in six of seven patients. Immunoglobulin E immunoblotting with Bruchus and infested lentils extracts revealed protein bands that were reactive to serum IgE from six and four, respectively, out of 16 patients. These patients had no IgE to lentil-specific proteins as determined by immunoblotting and Len c 1-specific IgE test. CONCLUSIONS: Lentil pest proteins can be a cause of IgE-mediated rhinoconjunctivitis and asthma in patients eating or inhaling infested lentil particles.     

Skin prick test reactions to brewer's yeast (Saccharomyces cerevisiae) in adult atopic dermatitis patients

The sensitizing capacity of brewer's yeast ( Saccharomyces cerevisiae ) was studied with the skin prick test method in 449 subjects, including 226 atopic dermatitis (AD) patients, 50 patients with allergic rhinitis (AR) and/or asthma (A), and 173 nonatopic controls. A positive SPT reaction (≥++) was seen in 94% of patients with severe AD, in 76% with moderate AD, and in 25% with mild AD or no history of AD. Patients with AR and/or A and nonatopic controls displayed a positive reaction in only 8 and 2% of cases, respectively. There was also a parallel skin prick test reactivity with other yeasts including Pityrosporum ovale and Candida albicans , suggesting cross-reactivity. Parallel skin reactivity was observed also with molds and animal dander but not with pollen or house-dust mite. A significant correlation was also found between total serum IgE level and skin prick test (SPT) results with S. cerevisiae .     

Allergy to kiwi in patients with baker's asthma: identification of potential cross-reactive allergens

BACKGROUND: Baker's asthma is a frequent IgE-mediated occupational disorder mainly provoked by inhalation of cereal flour. Allergy to kiwifruit has being increasingly reported in the past few years. No association between both allergic disorders has been described so far. METHODS: Twenty patients with occupational asthma caused by wheat flour inhalation were studied. Kiwi allergens Act d 1 and Act d 2 were purified by cation-exchange chromatography. Wheat, rye, and kiwi extracts, purified kiwi allergens, and model plant glycoproteins were analyzed by IgE immunodetection, enzyme-linked immunosorbent assay (ELISA), and inhibition ELISAs. RESULTS: Kiwifruit ingestion elicited oral allergy syndrome in 7 of the 20 patients (35%) with baker's asthma. Positive specific IgE and skin prick test responses to this fruit were found in all these kiwi allergic patients, and IgE to Act d 1 and Act d 2 was detected in 57% and 43%, respectively, of the corresponding sera. Actinidin Act d 1 and bromelain (harboring cross-reactive carbohydrate determinants) reached above 50% inhibition of the IgE binding to wheat and/or kiwi extracts. CONCLUSIONS: A potential association between respiratory allergy to cereal flour and allergy to kiwifruit has been disclosed. Cross-reactive carbohydrate determinants and thiol-proteaseshomologous to Act d 1 are responsible for wheat-kiwi crossreactivity in some patients.     

Occupational allergy in horticulture: demonstration of immediate-type allergic reactivity to freesia and paprika plants

Patients A and M developed allergic symptoms when working in a greenhouse with paprika plants and freesia plants, respectively. The possible involvement of an IgE-mediated mechanism was investigated with the skin prick test, radioallergosorbent test (RAST) and the histamine release test (HRT). Paprika flower, leaf and stem extract released 58, 47 and 43% of the total amount of histamine from washed leukocytes of patient A. In serum A IgE antibodies against paprika leaves and flowers could be demonstrated by RAST (11% binding of 125I-anti-IgE added). Freesia flower and stem extract released 46 and 43% histamine, respectively, from washed leukocytes of patient M. In the RAST, specific IgE antibodies against freesia flowers and stems were found in serum M (37% binding of 125I-anti-IgE added).