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Results for “Radioallergosorbent Test”

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PubMed1992

IgE antibodies to Pityrosporum orbiculare and Staphylococcus aureus in patients with very high serum total IgE.

Serum IgE antibodies were detected with the radioallergosorbent test (RAST) to a panel of allergens which included Pityrosporum orbiculare, Candida albicans, Trichophyton rubrum, Cladosporium herbarum, Staphylococcus aureus, animal dander, deciduous tree pollens, grass pollens and foods in 81 consecutive patients with total IgE greater than or equal to 3000 kU/l. Data on atopic and infectious disease characteristics were collected by a questionnaire. IgE antibody concentrations to P. orbiculare were significantly higher than to the other fungi and of the same magnitude as those to animal danders and pollens. High levels of P. orbiculare IgE antibodies were associated with current eczema, especially when it was the only atopic manifestation and demanding specialist care. IgE antibodies to P. orbiculare had the best explanatory value for current eczema in logistic regression analysis. Head-neck-face dermatitis was also associated with high levels of specific IgE to the yeast. IgE antibodies to S. aureus were detected in few patients and at low concentrations. Six patients had a history of systemic staphylococcal infections and presented a clinical picture, which was very similar to the hyperimmunoglobulinaemia E syndrome. Among the six were the two cases with the highest levels of IgE antibodies to S. aureus. The demonstration of high levels of IgE antibodies to P. orbiculare, which is a major part of human normal skin microflora, suggests that allergy to this yeast plays an important pathogenic role in eczema.

Adolescent↗

PubMed1997

Calcium intake in children with positive IgG RAST to cow's milk.

OBJECTIVE: This study was made to: (i) identify the prevalence of low calcium intakes in a paediatric population with loosely defined 'milk allergy'; and (ii) assess long-term (mean 21 months later) changes in calcium intake following a single nutrition counselling session with those patients initially found to have a low intake. METHODOLOGY: Calcium intake was assessed in a cross-sectional study of 58 patients ages 5-16 years (mean 9.9 years) with IgG radioallergosorbent test (RAST) class II or higher for cow's milk protein. Those 31 patients found to have a low calcium intake were prospectively re-evaluated 12-30 months later following a single nutrition counselling session. RESULTS: Calcium intake was < recommended dietary allowance (RDA) for 31 of 58 (53%) patients. The patient's perception of their intake was unreliable; 44% of those who rated their calcium intake fair or good did not meet their RDA. Taking a calcium supplement did not ensure adequate intake; 21% of those taking supplements still did not meet their RDA. Milk intake predicted calcium intake; 8% of those who did not drink milk vs 68% of those who did drink at least some milk met their RDA without supplementation. The 31 patients with low intakes received counselling and were re-evaluated at an average follow-up of nearly 2 years. Calcium intake was increased a mean of 360 mg/day and use of supplements increased from 10 to 52% of the group. Despite these positive changes, 48% still did not meet their RDA. CONCLUSION: Limited milk intake is likely to be associated with suboptimal calcium intake. Efforts should be made to educate the family about the importance of calcium and its non-dairy sources. With many families repeated discussions of this issue may be necessary to influence calcium intake.

Adolescent↗

PubMed1998

Analysis of the cross-reactivity between BtM and Der p 5, two group 5 recombinant allergens from Blomia tropicalis and Dermatophagoides pteronyssinus.

BACKGROUND: In tropical climates, sensitization to Bloma tropicalis and Dermatophagoides pteronyssinus is high and mainly directed to species-specific allergens. There is some cross-reactivity between extracts of these mites, probably due to the group 5 allergens that have high sequence homology. OBJECTIVE AND METHODS: We used the radioallergosorbent test (RAST), RAST inhibition and immunoblotting inhibition experiments to investigate the cross-reactivity between the recombinant allergens BtM and Der p 5, expressed as glutathione S-transferase fusion proteins, to detect the epitopes involved and to analyze the importance of this cross-reactivity. RESULTS: Seventy-nine percent of 48 patients sera were RAST positive to both recombinants, with a strong correlation (r = 0.8, p<0.0001). BtM inhibited 25 and 21.1% of IgE-binding to B. tropicalis and D. pteronyssinus extracts respectively and Der p 5 inhibited 22 and 24% of IgE-binding to D. pteronyssinus and B. tropicalis extracts. Furthermore, BtM inhibited 74.5% of IgE binding to Der p 5 and Der p 5 inhibited 72.4% of IgE-binding to BtM. RAST inhibition with BtM-derived synthetic peptides showed that peptide 4 (residues 35-50) and peptide 5 (residues 46-61) inhibited 37 and 16% of IgE-binding to BtM while peptides 5 and 2 (residues 14-30) were able to inhibit the IgE binding (32 and 28%, respectively) to Der p 5. CONCLUSION: There is cross-reactivity between BtM and Der p 5, which explains almost all the cross-reactivity between the two mite extracts. This cross-reactivity seems to be related to epitope(s) at the C-terminal segment of these allergens.

Allergens↗

PubMed1994

Bone mineralization in children and adolescents with a milk allergy.

To evaluate the correlation between dietary calcium intake and mineralization of the immature skeleton 55 children and adolescents aged 5-14 years (mean, 9.5 years) with a positive radioallergosorbent test (RAST) for serum antibodies to cow's milk protein were evaluated. Bone mineral density (BMD) in the lumbar spine and proximal femurs were measured by dual energy X-ray absorptiometry. BMD at each site for each subject was converted to an age-adjusted Z score based on our own series of 95 normal pediatric controls. Calcium intake was determined using a detailed food frequency questionnaire administered by a nutritionist during a 30-40-min interview. Dietary adjustments to the condition varied and resulted in a wide range of calcium intakes. Calcium supplements were taken by 22% of the subjects and were included in the determination of daily calcium intake. The group of 55 subjects was divided into quartiles based on calcium intake (mean +/- S.E mg calcium/day): Group 1, 409 +/- 21, Group 2, 663 +/- 16, Group 3, 950 +/- 32, Group 4, 1437 +/- 124. Bone density Z scores in the proximal femur serially increased across the calcium intake groups (mean +/- S.E.): Group 1, -0.16 +/- 0.31; Group 2, 0.05 +/- 0.33; Group 3, 0.44 +/- 0.24; Group 4, 0.79 +/- 0.41 (P = 0.03). A similar pattern was found with lumbar spine BMD Z scores: Group 1, -0.16 +/- 0.27; Group 2, 0.10 +/- 0.21; Group 3, 0.18 +/- 0.20; Group 4, 0.30 +/- 0.25 (P = 0.05). These data add further to the evidence that dietary calcium intake is important for optimal mineralization of the growing skeleton.

Absorptiometry, Photon↗

PubMed1984

Determinants of ryegrass pollen cytochrome c recognized by human IgE and murine monoclonal antibodies.

In attempts to produce fragments of an allergenic molecule which would retain allergenic and/or antigenic determinant(s), the cytochrome c of ryegrass (RG) pollen, which had been shown to be an allergenic constituent of this pollen, was digested with trypsin and chymotrypsin and the resulting fragments were separated by high performance liquid chromatography. Several of these fragments were shown, with the aid of the radioallergosorbent test and solid phase radioimmunoassays, to bind IgE antibodies present in a pool of six sera from grass-sensitive patients and three murine monoclonal antibodies, designated as Mab 41, Mab 42 and Mab 43, which had been originally produced against the crossreacting cytochrome c of Kentucky bluegrass (KBG). In summary, (i) fragments C-67 and C-74 reacted with all antibodies, (ii) fragments T-45, T-46 and C-69 bound to human IgE antibodies as well as to Mab 41 and Mab 42, but not to Mab 43, (iii) fragment T-44 reacted only with Mab 41 and Mab 42, and (iv) fragment C-83 bound only Mab 42 and Mab 43. On the basis of these results, it is concluded that (i) immunochemically active fragments of the RG cytochrome c can be readily produced by enzymatic degradation, (ii) there is significant crossreaction between the antigenic determinants of RG and KBG cytochromes c, (iii) whereas all fragments possessed at least two of the original antigenic determinants, fragments C-83 and T-44 were devoid of allergenic determinants, (iv) the antigenic determinants recognized by Mab 41 and Mab 42 were different from those reacting with human IgE antibodies and Mab 43, (v) each of the three monoclonal antibodies recognized a distinct antigenic determinant, (vi) fragments C-67 and C-74 possessed all determinants recognized by the human IgE and mouse antibodies used.

Animals↗

PubMedDate not supplied

Proliferative responses of lymphocytes to food antigens are useful for detection of allergens in nonimmediate types of food allergy.

Food allergy is clinically classified into two types, immediate and nonimmediate. Radioallergosorbent test (RAST) is a sensitive procedure for the diagnosis of IgE-mediated hypersensitivity but not for other types of hypersensitivity. There is not yet a sensitive blood examination for detection of allergens in nonimmediate types of food allergy. Of the total number of subjects in our study, twenty-two children had nonimmediate types of food allergy (hen's egg, cow's milk, soybean, or buckwheat flour), atopic dermatitis, allergic tension fatigue syndrome or pulmonary hemosiderosis. For these children, manifestations of the allergy did not appear earlier than 2 hours after ingestion of the offending food. Eighteen children in the study developed acute urticaria, angioedema, or bronchial asthma appearing within 2 hours of the challenge. Fifteen nonatopic healthy children were selected as controls. Proliferative responses of peripheral blood mononuclear cells (PBMCs) to food antigens were measured in nonimmediate types of food allergy. The proliferative responses of PBMCs to each offending food antigen in patients with nonimmediate types of food allergy were significantly higher than those of healthy controls and patients with immediate types of food allergy, respectively. Moreover, in each case with nonimmediate type, the proliferative responses to food antigens other than the offending food were not detected. When PBMCs were twice stimulated with the offending food antigen, the same results were obtained. These results indicate that the proliferative response of PBMCs to food antigens is specific to each offending food antigen in nonimmediate types of food allergy. Taken together, proliferative responses of PBMCs to each food antigen are useful for detection of allergens in nonimmediate types of food allergy.

Adolescent↗

PubMed2000

Dose-response in double-blind, placebo-controlled oral food challenges in children with atopic dermatitis.

BACKGROUND: Double-blind, placebo-controlled oral food challenges (DBPCFCs) are considered the "gold standard" for diagnosing food hypersensitivity, but the dose that elicits positive challenges, or determinants that may predict dose-response relationships, have not been reported. OBJECTIVE: Our purpose was to determine the quantity of food that elicits reactions during DBPCFCs and to evaluate parameters that may predict the provocative dose and severity of reaction. METHODS: We reviewed challenge data for all positive challenges to 6 common allergenic foods in children with atopic dermatitis evaluated for food allergy over a 13-year period. Challenge food was generally administered in 6 doses at 10- to 15-minute intervals beginning with 400 to 500 mg and completing with a total of 8 to 10 g of food. An open feeding of a larger portion followed negative challenges. At the physician's discretion, a lower starting dose was occasionally used (100 mg, 250 mg). Food-specific IgE antibody concentrations (radioallergosorbent test [RAST]) were determined on stored sera of 20% of the challenges selected randomly and 99.6% had prick skin tests (PSTs) performed to the challenged food. RESULTS: A total of 196 children (45% male; median age 5 y 9 mo; atopic dermatitis 98%, asthma 62%) had 513 positive challenges distributed as follows: egg 267, milk 117, soy 53, wheat 40, peanut 24, fish 12. The percentage of children reacting at the first dose (500 mg or less) was as follows: egg 49%, milk 55%, soy 28%, wheat 25%, peanut 26%, and fish 17%. Twenty-six milk challenges and 22 egg challenges were positive at a first dose of 250 mg; 3 milk challenges and 7 egg challenges were positive at a first dose of 100 mg. Eleven percent of the reactions that occurred on the first dose were severe. The percentage reacting after the final dose of the DBPCFC (or during open challenge) were egg 11%, milk 12%, soy 19%, wheat 12.5%, peanut 8.7%, and fish 25%. There was not a strong correlation between PST absolute wheal size or score (adjusted for histamine controls) and dose at reaction or severity of reaction (R(s) range -0.22 to 0.39 for particular foods). Serum concentration of food-specific IgE did not correlate well with the dose causing a reaction or with severity (R(s) range -0.40 to 0.55 for particular foods). CONCLUSIONS: This food-allergic population may react to as little as 100 mg of food, possibly less, and the dose causing a reaction and the severity of reaction is not predicted by PST or RAST. Lower doses (100 mg or less) should be investigated for their appropriateness in initiating DBPCFCs.

Administration, Oral↗

PubMed1992

Specific serum immunopatterns in clinical phases of allergic bronchopulmonary aspergillosis.

Immunoblotting, radioallergosorbent test (RAST), and enzyme-linked immunosorbent assay (ELISA) were performed to determine specific IgE and IgG responses to Aspergillus fumigatus (Af) allergens (IgE-Af; IgG-Af). Serology results were compared in patients with allergic bronchopulmonary aspergillosis (ABPA) (n = 43), patients with Aspergillus fumigatus-associated asthma (Af-asthma) (n = 26), and healthy individuals (n = 3). In patients with different clinical phases of ABPA, three specific immunopatterns were found by immunoblotting. It is proposed to classify ABPA into the active, intermediate, and remission phase with respect to the specific immunoresponse to Af-allergens and asthma symptoms. First, the active phase of ABPA is characterized by a fully developed specific immunoresponse to Af-allergens and severe asthma. Second, the intermediate phase includes patients with elevated specific immunologic findings without asthma symptoms. Third, the remission phase is characterized by a weak specific immunoresponse to Af-allergens after a long-term asymptomatic period. No correlation occurred between specific immunopatterns and irreversible brochopulmonary lesions. The IgE-Af RAST and IgG-Af ELISA titers of patients with ABPA in the active and intermediate phase were significantly higher compared with patients with ABPA in remission phase and with patients with Af-asthma. In particular, the demonstration of positive IgG-Af ELISA titer generally allows the serologic discrimination of patients with asthma and ABPA from patients with Af-asthma in clinical practice. The present study revealed that immunoblots of most patients with Af-asthma were negative. Immunoblotting demonstrated an IgG reactivity exclusively to low molecular weight (MW) Af-allergens in 8 out of 26 patients with Af-asthma and in the three healthy individuals, and this IgG response may reflect naturally occurring antibodies.

Antigens, Fungal↗

PubMed2002

Evaluation of dietary intake of vitamin E in the treatment of atopic dermatitis: a study of the clinical course and evaluation of the immunoglobulin E serum levels.

BACKGROUND: Vitamin E (VE) is a potent antioxidant that can improve the immune macrophage-mediated response, decrease the production and/or release of prostaglandins in humans, and decrease the serum levels of immunoglobulin E (IgE) in atopic subjects. AIM: To compare the effects of placebo (PL) and VE intake (400 IU/day) on subjective symptoms and serum IgE levels in 96 subjects with atopic dermatitis. MATERIALS AND METHODS: A single-blind clinical analysis was performed on 96 subjects randomly divided into two groups. Fifty subjects were given orally 400 IU (268 mg) of VE of natural origin, once a day for 8 months, and 46 took PL for the same period. Complete blood count, serum IgE levels, radioallergosorbent test (RAST) score, antinuclear antibodies (ANA), and biochemical analysis were obtained at the time of enrollment and every 15 days during the 8 months of the study. To evaluate VE therapy, a questionnaire was sent to each subject for completion at the end of the study. RESULTS: The results were as follows: (A) four subjects treated with VE worsened, compared to 36 in the PL group; (B) six subjects in the VE group and five in the PL group showed no change; (C) slight improvement was observed in 10 subjects in the VE group and four in the PL group; (D) 23 of the 50 subjects treated with VE showed great improvement, compared to only one in the PL group; and (E) there was almost complete remission of atopic dermatitis in seven of the 50 subjects in the VE group, but none in the PL group. Females showed less progression of atopic dermatitis than males in both groups and a higher percentage of almost complete remission (five females and two males). The range of serum IgE levels varied markedly from 1005 to 490 IU/mL in the VE group and from 1239 to 812 IU/mL in the PL group over 8 months. Subjects with great improvement and near remission of atopic dermatitis in the VE group demonstrated a decrease of 62% in serum IgE levels based on initial conditions, while, in subjects taking PL, the difference was approximately 34.4%. No complications were observed in either group. A remarkable improvement in facial erythema, lichenification, and the presence of apparently normal skin was reported. Eczematous lesions healed mostly as a result of decreased pruritus. CONCLUSIONS: The correlation between VE intake, IgE levels, and the clinical manifestations of atopy indicates that VE could be an excellent therapeutic tool for atopic dermatitis.

Adolescent↗

PubMed2004

Bee moth (Galleria mellonella) allergic reactions are caused by several thermolabile antigens.

BACKGROUND: Exposure and contact with bee moth (Galleria mellonella) larvae (Gm) can cause an allergic reaction both in anglers and breeders. We described the case of an amateur fisherman who experienced an allergic reaction using Gm but not using heat-treated Gm (h-Gm) (mummies). The aim of this study was to demonstrate by immunoblotting and radioallergosorbent test (RAST)-inhibition experiments the loss of allergenic epitopes in h-Gm extracts. METHODS: Galleria mellonella larvae and h-Gm were homogenized and extracted at 10% (w/v) in 0.5 M phosphate-buffered saline, pH 7.4 containing 0.5% NaN(3) for 16 h at 4 degrees C. Gm and h-Gm extracts were electrophoresed in a 10% polyacrylamide precast Nupage Bis-Tris gel at 180 mA for 1 h and the resolved proteins stained with 0.1% Coomassie brilliant blue and the molecular weight calculated. For the immunoblotting detection of allergenic components the resolved extracts were transferred onto a nitrocellulose membrane and incubated with the patient's serum. Bound specific-IgE was detected by peroxidase-conjugated anti-human IgE. RAST inhibition experiments were performed according to the Ceska method. RESULTS: The protein profile of Gm and h-Gm extracts resulted markedly different in number, intensity and the position of bands, indicating that heat-treatment modifies the chemical-physical characteristics of the protein contents. The Gm extract showed a strong-coloured band at 73 kDa and more than 20 components ranging from 12 to 133 kDa; h-Gm showed two main band at 77 and 38 kDa and about 15 faint bands between 20 and 133 kDa apparently without any correspondence to the bands present in the Gm extract. Immunoblotting with the patient's serum demonstrated several bands of reactivity with the Gm extract ranging from 20 to 100 kDa and no recognizable bands, but only a diffuse smear with h-Gm. When used in a RAST inhibition experiment the h-Gm extract demonstrated an inability to compete with the Gm one for the binding to patient's IgE serum. CONCLUSIONS: The h-Gm seems to lose the allergenic epitopes and has two advantages for anglers: to avoid new possible sensitizations as well as allergic symptoms in sensitized people, without interfering with their skills and satisfaction in their fishing performance.

Adult↗

PubMed1993

Risk factors for acute wheezing in infants and children: viruses, passive smoke, and IgE antibodies to inhalant allergens.

OBJECTIVE: To examine the prevalence of viral infection, passive smoke exposure, and IgE antibody to inhaled allergens in infants and children treated for acute wheezing. DESIGN: Case-control study of actively wheezing children who were compared with children without respiratory tract symptoms. SETTING: University of Virginia Pediatric Emergency Room. PATIENTS: Convenience sample of 99 wheezing patients (2 months to 16 years of age) and 57 control patients (6 months to 16 years of age). MEASUREMENTS AND RESULTS: Serum IgE antibody to inhalant allergens, measured by radioallergosorbent test (RAST), was uncommon in wheezing and control patients under age 2. After 2 years of age, the percentage of RAST-positive patients increased markedly and was significantly higher in wheezing patients than controls after age 4 (72%, n = 54, and 30%, n = 40, respectively, P < .001). Total IgE levels and nasal eosinophilia were strongly correlated with a positive RAST after age 2. Viral pathogens, predominantly respiratory syncytial virus, were identified in nasal washes from 70% (n = 20) of wheezing patients younger than 2 years of age compared with 20% of controls (n = 10), P < .05. After age 2, viruses, particularly rhinovirus, were isolated in washes from 31% (n = 70) of wheezing patients, 64% of whom were also RAST-positive. Levels of cotinine, a nicotine metabolite, were elevated (> or = 10 ng/mL) in saliva from a large percentage of smoke-exposed, wheezing patients under 2 (74%, n = 19) compared with those over 2 (14%, n = 51), P < .001. Odds ratios for wheezing were significant for virus (8.2, confidence interval [CI] = 1.3 to 5.0), and cotinine (4.7, CI = 1.0 to 21.3) in children under 2, and IgE antibody by RAST (4.5, CI = 2.0 to 10.2), virus (3.7, CI = 1.3 to 10.6), and the combination of IgE antibody and virus (10.8, CI = 1.9 to 59.0) were significant risk factors after age 2. CONCLUSION: Wheezing children younger than 2 years of age had a high rate of viral infection and a low rate of IgE antibody to inhalant allergens. When these children were exposed to passive smoke, salivary cotinine levels were elevated suggesting heavy exposure. After 2 years of age, sensitization to inhaled allergens became increasingly important and viruses remained a significant risk factor for wheezing. These data support recommendations to reduce tobacco smoke exposure at home, especially for young patients, and to consider sensitization to inhaled allergens and allergen avoidance in wheezing children at an early age, particularly after age 2 years.

Adolescent↗

PubMed1996

Occupational asthma and rhinoconjunctivitis caused by senna.

Occupational sensitization to senna is seldom reported. We describe a 21-year-old male atopic factory worker who developed IgE-mediated asthma and rhinoconjunctivitis 5 months after exposure to senna while he was working for a company manufacturing hair dyes. In the bronchial challenge test with senna, he exhibited a strong reaction. The skin prick test gave a 12-mm wheal reaction. The radioallergosorbent test (RAST) with senna was highly positive (33.6 PRU/ml, class 4), and could not be inhibited with pollens or foods. In protein staining with SDS-PAGE, two heavy bands were detected in senna at about 14 and 25 kDa, and two faint bands were visible at 19 and 21 kDa, In IgE immunoblotting with the patient's serum, one heavy band was detected at about 16 and four faint bands at 23, 25, 28, and 38 kDa. The patient became symptom free after he had changed his job within the same company.

Adult↗

PubMed1999

Rhinovirus and respiratory syncytial virus in wheezing children requiring emergency care. IgE and eosinophil analyses.

This cross-sectional emergency department study of 70 wheezing children and 59 control subjects (2 mo to 16 yr of age) examined the prevalence of respiratory viruses and their relationship to age, atopic status, and eosinophil markers. Nasal washes were cultured for respiratory viruses, assayed for respiratory syncytial virus (RSV) antigen, and tested for coronavirus and rhinovirus RNA using reverse transcription-PCR (RT-PCR). Also evaluated were eosinophil numbers and eosinophil cationic protein (ECP) in both nasal washes and serum, along with total IgE and specific IgE antibody in serum. Respiratory viruses were detected in 82% (18 of 22) of wheezing infants younger than 2 yr of age and in 83% (40 of 48) of older wheezing children. The predominant pathogens were RSV in infants (detected in 68% of wheezing subjects) and rhinovirus in older wheezing children (71%), and both were strongly associated with wheezing (p < 0.005). RSV was largely limited to wheezing children younger than 24 mo of age, but rhinovirus was detected by RT-PCR in 41% of all infants and in 35% of nonwheezing control subjects older than 2 yr of age. After 2 yr of age the strongest odds for wheezing were observed among those who had a positive RT-PCR test for rhinovirus together with a positive serum radioallergosorbent testing (RAST), nasal eosinophilia, or elevated nasal ECP (odds ratios = 17, 21, and 25, respectively). Results from this study demonstrate that a large majority of emergent wheezing illnesses during childhood (2 to 16 yr of age) can be linked to infection with rhinovirus, and that these wheezing attacks are most likely in those who have rhinovirus together with evidence of atopy or eosinophilic airway inflammation.

Adolescent↗

PubMed1999

Asthma in tunnel workers exposed to synthetic resins.

OBJECTIVES: The prevalence of asthma among tunnel workers exposed to synthetic resins was studied by determining airway symptoms, methacholine responsiveness, and lung function. METHODS: Nineteen injection workers were compared with a group of 104 other tunnel workers with similar exposure, except for that to synthetic resins. A questionnaire on respiratory symptoms, smoking habits, use of respiratory protection, and work tasks was used. Lung function was studied using a bellows spirometer. Bronchial reactivity was tested with methacholine. Allergy screening with Phadiatop and radioallergosorbent tests for toluene-diisocyanate-HSA, diphenylmethane-4.4-diisocyanate-HSA, and formaldehyde-HSA (HSA = human serum albumin) were carried out. Methylene diphenyl diisocyanate (MDI) and MDI prepolymer exposure was estimated by filter sampling, and the filters were analyzed by high-performance liquid chromatography. The most common work situations were simulated for an estimation of exposure to isocyanates. RESULTS: The injection workers reported more respiratory symptoms than the reference group, and they had higher prevalences of bronchial hyperresponsiveness (37% versus 14%), asthma (26% versus 1%), and airflow limitation (37% versus 4%). Toluene-diisocyanate-HSA-specific immunoglobulin E antibodies were found in 2 of the 19 injection workers, but in none of the other tunnel workers. By simulation at a worksite, the average exposure to polymerized MDI was estimated to be 5.5-300 microg/m3 during injection work and 18-4300 microg/m3 during short-term exposure, the highest exposure occurring when cured polyurethane was ground. CONCLUSIONS: Exposure to partly decomposed MDI in tunnel work enhances the risk for respiratory symptoms, methacholine hyperresponsiveness, asthma, and airflow limitation.

Adult↗

PubMed1991

Purification and characterization of the glycoprotein allergen from Prosopis juliflora pollen.

Highly active glycoprotein allergens have been isolated from pollen of Prosopis juliflora by a combination of Sephadex G-100 gel filtration and Sodium dodecyl sulphate-Poly-acrylamide gel electrophoresis. The glycoprotein fraction was homogeneous, and had molecular weight 20,000. The purified glycoprotein allergen contained 20% carbohydrate, mainly arabinose and galactose. Enzymatic digestion of glycoprotein with protease released glycopeptides of molecular weight ranging from less than 1,000 to more than 5,000 on Sephadex G-25 gel filtration. Antigenicity or allergenicity testing of these glycopeptides by immunodiffusion, immunoelectrophoresis, and radioallergosorbent test indicated complete loss of allergenic activity after digestion with protease whereas incubation with beta-D-galactosidase and periodate oxidation had little affect on the allergenic activity of the glycoprotein fraction. But incubation with alpha-D-glucosidase did not affect the allergenic activity significantly. All these tests indicated that protein played significant role in allergenicity of P. juliflora pollen.

Allergens↗

PubMed1983

Skin testing for allergy in children.

In diagnostic testing for IgE-mediated allergy in children the skin-prick test is preferred because it is safer, less painful and more specific than the intracutaneous test, and cheaper and more sensitive than the radioallergosorbent test (RAST). The intracutaneous test and RAST are useful in certain circumstances, however. While a positive result from any of these tests indicates hypersensitivity, it does not necessarily mean that the allergen giving the positive result is responsible for the patient's symptoms. That can only be decided by interpreting the result in light of the allergy history. This paper outlines the indications for the prick test, the allergens that may be employed, the method of doing the test, and its place among the other tests that are used in a modern pediatric allergy practice.

Asthma↗

PubMed1993

Intestinal reactivity in allergic and nonallergic patients: an approach to determine the complexity of the mucosal reaction.

BACKGROUND: To determine whether inflammatory markers and mediators were released in response to different intestinal antigens, studies were performed in atopic patients allergic to birch, patients allergic to psyllium powder (ispaghula), and patients intolerant to milk. METHODS: Allergy to birch and psyllium powder was documented by the presence of circulating IgE antibodies and positive skin tests. Patients intolerant to milk had negative outcomes of radioallergosorbent tests and skin tests but positive results of double-blind, placebo-controlled tests. Challenge of the intestine with different antigens was achieved by perfusion of a jejunal segment occluded between balloons. Basal and antigen-activated release of mast cell/basophil and eosinophil products and of substances emanating from the plasma and interstitial fluid was compared in perfusate fluid from patients (n = 8) and matched healthy controls (n = 8). RESULTS: Perfusate levels of albumin and hyaluronan (previous name hyaluronic acid) were increased threefold to fivefold by antigen in all patients, but not in controls. Eosinophilic cationic protein increased in patients but also in ispaghula controls. Histamine was released in response to milk, but not in patients allergic to birch or ispaghula. Prostaglandin E2 increased in milk- and birch-sensitive patients. In response to ispaghula, however, it was released in both patients and controls. CONCLUSIONS: We conclude that subclinical intestinal challenge with antigen induces an increase in the appearance rate of albumin and hyaluronan in the intestinal lumen both in atopic patients (with target organs such as the lungs or nose and eyes) and in patients with intestinal intolerance to milk. These changes in permeation are similar to those reported from other organs such as the lung. They may reflect a common response in early phase I reactions that are either IgE-mediated or occur in response to food antigens without any obvious involvement of an IgE-mediated mechanism. Subclinical provocation with intestinal antigens should prove useful for further elucidation of mechanisms underlying intestinal mucosal reactions to exogenous stimuli.

Antigens↗

PubMed1999

Allergies and vocal fold edema: a preliminary report.

This paper describes different tools to rule out the etiology of vocal fold edema. A complete voice assessment is used in our Voice Center. This includes patient history, acoustic analysis, laryngeal video-stroboscopy, otolaryngology consultation, allergy testing from our Allergy Clinic, and gastroenterology consultation as appropriate. Inhalant allergy can be a hidden, yet very common cause of chronic laryngitis. Respiratory allergies can also cause decreased pulmonary function; excessive secretions in either the lower airway, trachea, bronchi or in the upper airway of the pharynx; edema of the vocal folds themselves; and unusual resonance characteristics of the pharynx or nasal cavity due to congestion of the membrane in those areas. Voice patients with a history of seasonal hay fever, a history of allergic reactions around cats or dogs, or a strong family history of allergies should be allergy tested. Screening tests for allergies are available, which include a screening radioallergosorbent test or a screening panel of scratch or intradermal skin tests. Once specific allergens are identified, recommendations for therapy or other intervention can be made. Straining the voice, in combination with the above conditions, can increase the voice problem. The histories, allergy test results, and voice laboratory evaluations of several patients are described. Identifying these voice patients and treating their allergies are important in keeping these patients healthy and maintaining a clear, good voice quality. The multidisciplinary approach in voice disorders is indispensable in diagnosis and treatment of these disorders.

Adult↗