Hyposensitization with Dermatophagoides pteronyssinus in house dust allergy: a controlled study of clinical and immunological effects

A double-blind statistically controlled study was carried out on ninety-six patients with Type I allergy to D. pteronyssinus and a history of perennial asthma and/or rhinitis. Forty-eight received injections of an extract of Dermatophagoides pteronyssinus and forty-eight controls received injections of carbol saline. Both groups were closely comparable in all respects. Ninety-one were available for assessment, forty-six controls, and forty-five treated. The D. pteronyssinus treated group showed a statistically significant decrease in nasal sensitivity to the mite extract after treatment and recorded less asthma, less use of drugs and an increased clinical tolerance of household dust. A significant rise in specific IgE to D. pteronyssinus was found in twenty-three out of forty (58%) of the treated compared with eight out of forty-one (20%) of the controls and a rise in total IgE in twenty out of forty (50%) of the treated compared with nine out of thirty-nine (23%) of the control group. Specific IgG antibodies to D. pteronyssinus were found prior to treatment in twelve out of thirty-nine (30%) of controls and twelve out of forty (31%) of the treated group. There was a significant increase in the number of patients with specific IgG antibody after injections of D. pteronyssinus extract as compared with the controls. This increase was associated with clinical improvement which occurred mainly in subjects who showed a decrease, little change or an increase of less than 30% in specific IgE antibody. In those with an increase of more than 30% in specific IgE antibody there was no evidence of clinical improvement even if specific IgG was produced. Diminished release of histamine from leucocytes was found after treatment in six out of ten treated compared with three out of eleven controls. There were, however, no differences between treatment and control groups in lymphocyte transformation and the liberation of leucocyte inhibitory agents. Clinical improvement was significantly better in those treated patients who gave strong nasal and skin reactions before treatment than in those with weak nasal and skin reactivity, who were no different from the controls.     

<Emphasis Type="Italic">Dermatophagoides pteronyssinus</Emphasis> and <Emphasis Type="Italic">Tyrophagus putrescentiae</Emphasis> Allergy in Allergic Rhinitis Caused by Cross-reactivity Not Dual-Sensitization

Tyrophagus putrescentiae and Dermatophagoides pteronyssinus are causative factors for the development of airway hypersensitivity. The main objective in this study was to identify the cross-reactive allergens between T. putrescentiae and D. pteronyssinus and investigate their sensitization in patients with allergic rhinitis. The prevalence of sensitization to mites was determined by skin prick tests and histamine release assays. Both immunoblot and ELISA inhibition assays were performed by using the recombinant allergens of T. putrescentiae and D. pteronyssinus. The cross-reactive allergens were identified by using IgE-binding inhibition analysis. The correlations of specific IgE between T. putrescentiae and D. pteronyssinus to group 2 and group 3 mite allergens were compared. A total of 117 allergic rhinitis patients, aged between 16 and 40 years old were recruited to be included in this study. The results showed that 70% (82/117) of allergic rhinitis subjects had skin test positive reactions to D. pteronyssinus or T. putrescentiae. Among these mite-sensitive subjects, there were 81 subjects (81/82) sensitive to D. pteronyssinus and 34 subjects (34/82) sensitive to T. putrescentiae. Among the T. putrescentiae hypersensitive subjects, 97% (33/34) were also sensitized to D. pteronyssinus. In the IgE-binding inhibition analysis, 59% (13/22) subjects had IgE-binding activity of T. putrescentiae that was completely absorbed by D. pteronyssinus, especially components with MW at 16 kDa. In ELISA inhibition testing, 69% of IgE-binding was inhibited by rTyr p 2, and 45% inhibited by rTyr p 3. The titers of IgE antibodies to rTyr p 2 and rDer p 2 were well correlated, but not rTyr p 3 and rDer p 3. In conclusion, most T. putrescentiae sensitized subjects were also sensitized to D. pteronyssinus in young adult allergic rhinitis patients. The complete absorption of IgE binding activity by D. pteronyssinus indicates that T. putrescentiae hypersensitivity might be due to the cross-reactivity, not dual-sensitization of D. pteronyssinus and T. putrescentiae. The IgE-binding titers of group 2 allergens were well correlated and the binding activity of Tyr p 2 could be absorbed by Der p 2, suggesting that group 2 allergens are the major cross-reactive allergen of D. pteronyssinus and T. putrescentiae.     

Allergy to castor bean in The Sudan: measurement of serum IgE and specific IgE antibodies

Allergy to castor bean was diagnosed in thirty-nine dockworkers from Port Sudan, on the basis of rhinitis and/or asthma provoked by castor bean dust, together with a positive prick test to a high dilution of castor bean extract. These were compared to twelve non-allergic dockworkers from Port Sudan and forty-three other Port Sudan residents. The castor bean allergic group had significantly higher IgE levels (mean 902 iu/ml) than the non-allergic dock workers (mean 245 iu/ml) or the Port Sudan residents (mean 404 iu/ml) P<0.01, IgE antibody to castor bean was detected in all the castor bean-allergic group, and also in 25-35% of the Port Sudan resident group, but at a much lower level. No evidence was found to support the view that parasitic infestation (evidenced by IgE antibodies to Ascaris lumbricoides) prevented sensitization to castor bean or any other allergen. There was a higher incidence of IgE antibodies to Dermatophagoides pteronyssinus in the castor bean-allergic dockworkers (18/36) than in the non-allergic Port Sudan residents (5/43), although we were unable to show that sensitivity to other inhalant allergens pre-disposed to castor bean allergy.     

Exposure and sensitization to dust mite allergens among asthmatic children in Sao Paulo, Brazil

A group of 20 mite allergic asthmatic children aged 6-12 years old. living in Sao Paulo, Brazil, was studied regarding their degree of sensitization to house dust mites and exposure to mite allergens in their homes. In 18 out of 20 houses at least one dust sample was obtained which contained > 10 μg Der p I/g of dust. The highest levels of Dermatophagoides pteronyssinm allergens, Der p I and Group II, were measured in bedding samples (geometric mean 38.4 and 36.6 μg/g, respectively), followed by bedroom floor, TV room and kitchen. Mite allergen levels in Brazilian houses were as high as those reported to be associated with sensitization and acute attacks of asthma in other parts of the world. In keeping with previous reports that D. farinae is rarely found in Brazil, Der fl was undetectable or found in very low levels (<0.5 μg/g). Levels of cat allergen Pel d I of > 8 μg/g of dust were obtained only in 2 houses only. Cockroach allergen Bia g I was detected in five out of 20 houses. Levels of IgE antibodies to D. pteronyssinus were > 200 RAST U/ml in 19 out of 20 children (geometric mean 1588 RAST U/ml). IgE antibodies to cat, cockroach, A. fumigatus, ragweed and rye grass pollens were undetectable or <80 RAST U/ml. IgE antibodies to the mite Blomia tropicalix were also measured, and levels >200 RAST U/ml were observed in 13 out of 20 sera. Immunoabsorption studies demonstrated that the bulk of the IgE- antibody to B. tropicafis (64%) was to species-specific allergens and that 36% were cross-reactive with D. pteronyssinus. The implication of our results is that management of children with asthma in São Paulo should include skin testing for allergy to both Dermatophagoides and B. tropicalis as well as recommendations about environmental control of house dust mite exposure.     

In vitro investigations in asthmatic children undergoing hyposensitization with tyrosine-adsorbed Dermatophagoides pteronyssinus antigen

Successful hyposensitization to Dermatophagoides pteronyssinus in perennial childhood asthma was associated with a slight mean rise of serum IgG antibody to the mite antigen in contrast to a placebo group in whom this antibody fell slightly. No relationship was detected between the effect on asthma and the magnitude of this change, Nor was there any consistent effect on IgE or IgA antibody. There was a wide range of total serum IgE and IgE, IgG and IgA antibody to D. pteronyssinus before treatment; this level did not predict the effect of treatment. Some patients lacked IgA antibody. IgE antibody to timothy grass pollen was raised in some but not others. These levels did not change systematically during the study and improvement occurred in those who had this antibody as well as IgE antibody to D. pteronyssinus. IgG and IgE antibodies to D. pteronyssinus were significantly correlated in the pre-treatment samples. Lymphocyte thymidine uptake was lower after 8 weeks of treatment than in the control group, not only after stimulus with D. pteronyssinus antigen, in vitro, but also with antigen from Candida albicans. This was not a serum effect. The late bronchial provocation response was lost only in those with serum IgA less than the log mean for age.     

Occupational allergy in greenhouse workers: sensitization to Tetranychus urticae

Background Tetranychus urticae (TU) is a macroscopic mite which is found infesting a large number of plants of economic interest. It has rarely been described as a cause of occupational allergic disease in agricultural workers. Objective To describe TU sensitization in greenhouse workers attending the outpatient allergy unit and its clinical associations, and to characterize the allergens involved. Materials and methods Twenty-four consecutive carnation greenhouse workers with allergy-related symptoms, referred to our outpatient clinic during a 6-month period, were included. We made the diagnostic extract from carnation leaves heavily infested with TU. Skin-prick test, specific IgE measurement and bronchial provocation test with TU extract were carried out in all subjects. Allergen characterization was achieved by SDS-PAGE (sodium dodecylsulfate-polyacrylamide gel electrophoresis) and immunoblotting Results Sixteen patients (66%) presented positive skin-prick test and specific IgE and were diagnosed allergic to TU. Fifteen patients suffered from bronchial asthma, 14 rhinitis and five urticaria. Twelve exibited positive bronchial provocation test to the TU extract. On RAST-inhibition studies, there was no evidence of crossreactivity between TU extract and D. pteronyssinus. An allergen at 19 kDa was determined in the TU extract by SDS-PAGE immunoblotting studies. Conclusion TU could be an important occupational allergen in greenhouse workers showing allergic symptomatology. There is no crossreactivity between this mite and the house dust mite D. pteronyssinus.     

Long-term falls in antibodies to dust mite and pollen allergens in patients with asthma or hay fever

‘Spontaneous’ improvement in, or alteration of, allergic symptoms is a common occurrence, and the immunological basis is of interest in attempts to develop effective specific therapy. In the present study we measured levels of serum antibodies to Dermatophagoides pteronyssinus in patients diagnosed as having house-dust-allergic asthma up to 40 years previously. The results show a progressive fall in both IgG and IgE antibodies to antigen P₁ and RAST binding lo crude D. pteronyssinus extract. By contrast changes in total serum IgE were not marked. Within each of the groups of patients diagnosed 20. 30 and 40 years previously, 70% no longer suffered severe symptoms. However, the absence of detectable IgE antibody in serum was neither a necessary nor a sufficient condition for loss of symptoms. A group of patients who had spontaneously recovered from hay fever had significantly lower IgG and IgE antibody for the major grass pollen allergen Rye I and also lower total IgE than current hay fever sufferers. In neither hay fever nor asthma was there evidence to link spontaneous improvement in symptoms with an increase in IgG antibodies.     

Characterization of Der p 21, a new important allergen derived from the gut of house dust mites

Background: The house dust mite (HDM) Dermatophagoides pteronyssinus is a major allergen source eliciting allergic asthma. The aim of the study was to identify new important HDM allergens associated with allergic asthma. Methods: A cDNA coding for a new mite allergen, designated Der p 21, was isolated using immunoglobulin E (IgE) antibodies from patients with allergic asthma out of a D. pteronyssinus expression cDNA library and expressed in Escherichia coli. Results: Circular dichroism analysis of the purified allergen showed that rDer p 21 (14 726 Da) is one of the few mite allergens with an α‐helical secondary structure. The protein exhibited high thermal stability and refolding capacity, and, as determined by small angle X‐ray scattering, formed a dimer consisting of two flat triangles. rDer p 21 bound high levels of patients’ IgE antibodies and showed high allergenic activity in basophil activation experiments. Rabbit anti‐Der p 21 IgG antibodies inhibited mite‐allergic patients’ IgE binding and allowed the ultrastructural localization of the allergen in the midgut (epithelium, lumen and faeces) of D. pteronyssinus by immunogold electron microscopy. Der p 21 revealed sequence homology with group 5 mite allergens, but IgE and IgG reactivity data and cross‐inhibition studies identified it as a new mite allergen. Conclusions: Der p 21 is a new important mite allergen which is liberated into the environment via faecal particles and hence may be associated with allergic asthma.     

SOME IMMUNOLOGICAL ASPECTS OF PATIENTS WITH RHINITIS IN LEBANON

ABSTRACT

Background: Hitherto immunological determinates in Lebanese patients with rhinitis have not been investigated.

Objective: To identify causative allergens in Lebanese patients with allergic rhinitis and determine possible correlation's among serum allergen specific antibody, polyclonal IgE, IL-4, IL-5 and peripheral eosinophil levels.

Methods: One hundred and thirteen patients with a long lasting history of nasal obstruction, rhinorrhea, sneezing and nasal itching were investigated. Serum allergen specific antibodies using a panel of 10 potential allergens, IL-4 and IL-5 levels were determined by enzyme immunoassays. Polyclonal IgE levels were estimated by an immunochromatographic assay and eosinophil counts by a Coulter STKS counter.

Results: Based on the presence of serum allergen-specific IgE antibodies, 74 patients were considered to have an allergic etiology. Polyclonal IgE levels were elevated in 41 of the 74 allergic rhinitis patients while the other 33 patients had normal serum levels. In the remaining 39 specific IgE antibody-negative patients, 32 had normal, and 7 had elevated, polyclonal IgE levels. IgE specific antibodies to more than one allergen were detected in 59 of 74 patients. The most common causative allergens were mite, Dermatophagoides pteronyssinus, Dpt (83.8%) and Dermatophagoides farinae, Df (78.4%). Analysis of the data indicated that elevated polyclonal IgE levels correlated with the concentration of serum specific IgE antibodies and the number of the detected causative allergens per patient. Fifty-nine of 74 allergic rhinitis patients had elevated IL-4 levels and 44 had elevated IL-5 levels. The number of allergic patients with both elevated IL-4 and IL-5 levels was 24. Finally, only 9 allergic rhinitis patients had peripheral eosinophilia.

Conclusion: Mite Dpt and Df were the most common causative agents of allergic rhinitis in the Lebanese group studied. A prerequisite for Specific Immunotherapy is the identification of the causative allergen. Determinations of polyclonal IgE level and peripheral eosinophil count alone, as an aid to diagnosis are insufficient and may be misleading. On the other hand, determination of all the parameters studied in conjunction appears to be of diagnostic value.     

A clinical evaluation in children of the Pharmacia ImmunoCAP system for inhalant allergens

Background The Pharmacia ImmunoCAP system (CAP) for assaying serum IgE specific antibodies was evaluated in a clinical setting against skin-prick test (SPT) perfonncd using Dome/Hollister-Steir allergen extracts. The five cotnmon inhalant allergens D. pteronyssinus. D. farinae, mould mix, grass mix and cat epithelium were tested concurrently by both methods in 167 children aged 7.5–12 years. The specific SPT for D. pteronyssinus and D. farinae were also tested against the CAP house dust mite (HDM) mix. Objective The purpose of the study was to determine the sensitivity and specificity of the Pharmacia ImmunoCAP system Tor detecting serum IgE specific antibodies to inhalant allergens in a clinical setting, using the SPT result as the ‘gold standard’. Methods The SPTs were performed using Dome/Hollister-Steir allergen extracts. The serum IgE specific antibodies were quantitated using the radioimmunoassay version of the Pharmacia ImmunoCAP system. A history of allergic disease was assessed using a validated questionnaire. Results SPT gave more positive reactions than CAP with the exception of cat epithelium. The concordance between SPT and CAP results was 91% over all the tests. The concordance with SPT was slightly higher for the specific CAP for D. pteronyssinus and D. farinae (93% and 95% respectively) than for the CAP HDM mix (86% and 90% respectively). There was a higher proportion of positive results for both SPT and CAP in the 115 children defined as having a history of allergic disease. Using SPT defined allergy as the gold standard, the sensitivity of the CAP system was 87% for the two specific house dust mites but was lower for cat epithelium (67%), mould mix (59%) and grass mix (46%). The sensitivity of the CAP system improved for D. pteronyssinus (96%) and the HDM mix (91%) when tested in subjects defined as having a history of allergy associated disease. The specificity of the CAP system showed less variation between allergens and ranged from 90–99%. Conclusion The results of this study of children aged 7.5–12 years demonstrate that, for the inhalent allergens tested, the Pharmacia ImmunoCAP system perfoms well in the setting of known allergic disease.     

Bronchial histamine reactivity: its relationship to the reactivity of the bronchi to allergens

The aim of this study was to examine the proposal that the magnitude of the response of the bronchi to an immediate allergic reaction depends not only on the degree of sensitization of the bronchi by allergen specific IgE antibody but also on the reactivity of the bronchi to the vasoactive mediators which are released during immediate allergic reactions. This was done by determining the bronchial reactivity to Dermatophagoides pteronyssinus and to histamine of both symptomatic and asymptomatic groups of atopic subjects who had comparable serum levels of D. pteronyssinus specific IgE. Positive bronchial responses to the D. pteronyssinus extract were recorded with both the symptomatic and asymptomatic subjects, the mean bronchial threshold dose of allergen being significantly higher in the asymptomatic than in the asthmatic patients. There was a highly significant correlation between the serum level of allergen specific IgE and the bronchial threshold dose of allergen extract and also between the bronchial threshold dose of allergen extract and of histamine in all groups of subjects. The ability to predict bronchial reactivity to the allergen from the serum level of allergen specific IgE within each group was significantly better if the bronchial reactivity to histamine was included in the correlation analysis. This supports the hypothesis that whether a particular subject who is producing specific IgE antibody will develop symptoms on the inhalation of that allergen depends not only on the amount of allergen which he inhales and on the degree of sensitization of his bronchi but also on the reactivity of his bronchi to the vasoactive mediators which are released by allergen–IgE interaction.     

Immunological features of asthma (Part II)

A serological comparison was made of two groups of 120 matched asthmatic and healthy subjects, between the ages of 20 and 49 years and matched for age and sex, in terms of serum total levels of IgG, IgM, IgA. IgD and IgE and of specific antibody levels in each immunoglobulin class to five common UK allergens. The relationship of clinical features to the serological tests was also examined in the asthmatic subjects. The following statistically significant findings were shown. The patients had higher levels than the controls of total globulins and of IgG, IgA and IgD but not IgM. In both patients and controls the females had higher IgM levels than the males. The total IgE levels were higher in patients than in the controls and the male patients had higher levels than the female patients. Total IgE levels were also related, to the numbers of first degree relatives with asthma, hay fever and eczema, to the severity of hay fever and to the amount of time off work in the male patients. In those male patients with exercise induced asthma the total IgE levels were lower than in those not showing this reaction. As for the other iminunoglobulins, the only significant differences were a higher [gG level in patients with FEV, or PFR>50% predicted and a higher IgD level in patients with hay fever. Radio-immunodiffusion tests for specific precipitins were positive for Dermatophagoldes pteronyssinus in comparable numbers of asthmatics (25.8%) and controls (21.7%). Positive precipitin tests were uncommon in tests with extracts of grass pollen, Aspergillus fumigatus, cat and dog hair in the patients and even less so in the controls. Positive RAST tests for specific IgE antibodies were obtained in patients and controls respectively, against D. pteronyssinus 59% and 11% grass pollen 37.0 and 12%, and A. fumigatus 6% and 4%. The male patients showed the closest significant relationship of specific IgE to D pteronyssinus and the history of house dust allergy, positive skin test and nasal test. in the females only the skin and specific IgE tests were related. Both sexes showed a significant association between specific IgE to grass pollen and positive skin tests and nasal tests, but only the males showed an association with the history. The size of skin test weal to D. pteronyssinus were related to the levels of specific IgE antibody, Correspondence: Professor J. Pepys, Cardiothoracic Institute, Brompton, London SW3 6HP. No differences were found between the four skin test groups and between the asthmatics and the control subjects in the incidence of bacterial precipitins and auin-antibodies.     

Serial IgE levels in allergic farmers related to the mite content of their hay

Asthma and allergic rhinitis in farmers has been shown to be associated with the large numbers of ‘storage mites’ present in stored hay (Cuthbert et al., 1979). During the year July 1977 to June 1978, studies were undertaken to compare the IgE levels to specific storage mites in the sera of five farming and one control subject, with the numbers of mites present in their hay. Samples of hay were collected at monthly intervals and the total number of mites per gram of hay in each sample recorded. Species were identified and approximate estimates of the number of two of these, Tyrophagus longior and Acarus farris, were made for two of the farms Crook and Queenalia, respectively. Blood samples were also taken at monthly intervals from all the subjects and assayed by radioallergosorbet test for specific IgE to five storage mite species and to the house-dust mite (Dermatophagoides pteronyssinus). Mite numbers, both in respect of total counts and specific estimates, showed a rapid increase to a peak during the month of October with a subsequent fall in November and a partial recovery in December, after which numbers tended to even out. Only two of the farmers showed consistently raised levels of specific IgE to any of the storage mite species and these tended to follow the fluctuations of the mite numbers during the months to January 1978, after which one farmer (J.M. from Crook) showed a fall in his positive IgE titre to T. longior, whilst the other (W.W. of Queenalia) who was positive to A. farris showed a sudden rise in titre to this species. High titres to the house-dust mite (D. pteronyssinus) were recorded in the sera of three of the farmers. One farmer (J.M.) whilst giving a persistently high titre of IgE to T. longior, gave only a low one of less than twice normal to Tyrophagus putrescentiae, demonstrating a specificity of sensitization to the more commonly occuring of two of the species of a single genus.     

The prevalence of immediate positive skin tests to Dermatophagoides pteronyssinus and grass pollen in schoolchildren

The prevalence of immediate positive reactions to prick testing with house dust mite (Dermatophagoides pteronyssinus) and grass pollen allergens was determined in a random sample of 303 children aged between 8 and 14 years from two Southampton schools. One hundred and two (33.7%) showed positive reactions, fifty to both D. pteronyssinus and grass pollen, thirty to D. pteronyssinus only and twenty-two to pollen only. Allergic symptoms were present in fifty-one of the 102 children with positive skin tests; amongst thirty children with D. pteronyssinus skin sensitivity by itself, only six had symptoms suggestive of allergic disorder. Significantly more children with positive than with negative tests were reported by their parents to have suffered from recurrent bronchitis during early childhood.     

Specific IgA and IgE in childhood asthma, eczema and food allergy

Allergen-specific IgA and IgE antibodies were compared in 250 children with asthma (Dermatophagoides pteronyssinus, rye grass pollen), in eighty-six children with eczema (whole egg, cow's milk) and in two groups of children with egg and cow's milk allergy. In each of the conditions investigated, food allergy, asthma and eczema, increasing atopy was associated with increasing specific IgE levels to relevant allergens. There was no association of high IgE antibody levels with low IgA antibody levels in any of the conditions or allergens studied. There was, however, a tendency for subjects with more severe asthma to have high IgA levels with high IgE levels. IgA deficiency does not appear to be associated with atopic conditions of childhood.     

The investigation of asthmatic children by multiple factor analysis. II. The influence of 17 allergic factors on atopic dermatitis and allergic rhinitis in asthmatic children

We investigated possible influence of 17 allergy-associated factors on atopic dermatitis and allergic rhinitis using Multiple factor analysis in 150 asthmatic children. Atopic dermatitis was complicated in ninety-seven cases and allergic rhinitis in ninety-seven cases. 17 allergy-associated factors were as follows: 1) sex, 2) age, 3) onset age of asthma, 4) family history of allergy, 5) peripheral eosinophil counts, 6) IgE RIST, 7) IgE RAST score to egg white, 8) IgE RAST score to milk, 9) IgE RAST score to soybean, 10) IgG4 antibody titers to egg white, 11) IgG4 antibody titers to milk, 12) IgG4 antibody titers to soybean, 13) IgE RAST score to house dust, 14) IgE RAST score to Dermatophagoides farinae, 15) severity of asthma, 16) exercise-induced asthma, 17) atopic dermatitis or allergic rhinitis. We concluded as follows: 1) Factors which more strongly influenced both atopic dermatitis and allergic rhinitis were IgE RAST score to D.f., positive family history of allergy, IgE RIST and eosinophil counts. 2) Combination with high levels of IgG4 antibody to 3 food allergens such as egg-white, milk and soybean and IgE RAST to egg-white has a strong influence on atopic dermatitis, but high levels of IgG4 antibody to 3 food allergens except high level of IgG4 antibody to soybean have a weak influence on allergic rhinitis.     

Immunological studies in asthmatic children undergoing antigen provocation in the skin, lung and nose

In children with perennial asthma, dual (immediate and late) reactions in the skin to D. pteronyssinus and Timothy grass pollen were more frequent with high doses of antigen and were associated with large immediate reactions. The frequency of dual bronchial or nasal reactions was not related to the size of the immediate reaction and dual reactions were commonly elicited to the lowest antigen dose which would elicit an immediate reaction. Serum IgG, IgA, IgM or IgE concentrations, IgE or IgG antibodies to the antigens and defective yeast opsonization did not differ in children with dual or immediate only reactions in skin, nose or lung. In five patients undergoing bronchial provocation tests with D. pteronyssinus there was no fever, no fine crepitations in the kings and no significant change in the levels of C3.     

Study of prolonged hyposensitization with D. pteronyssinus extract in allergic rhinitis

Sixty-six Chinese patients with rhinitis, with or without asthma, were randomly allocated to a course of injections either with D. pteronyssinus extract or placebo. The course consisted of 18–22 weekly injections, followed by monthly maintenance injections with the highest concentration for 1 year. Progress was evaluated by a patient's daily diary and monthly assessments by the physician, by comparisons of skin and nasal challenge tests and by the specific serum IgE concentration, before treatment, at the end of the weekly course, and once during the maintenance course. No improvement was detected at the end of the weekly course, but during maintenance there was a consistent benefit to the patients receiving the D. pteronyssinus extract both in the diary and the physician's assessment, especially the former. There was no consistent change in the skin or nasal challenge tests and there was a trivial fall in the serum IgE levels in the patients on the extract. Adverse reactions were much more common in the patients on the extract, but most were trivial. The different methods of assessment used and the role of hyposensitization with D. pteronyssinus are discussed.     

Non-specific airway hyperresponsiveness in mono-sensitive Sicilian patients with allergic rhinitis. Its relationship to total serum IgE levels and blood eosinophils during and out of the pollen season

Background Initial attempts to evaluate the association between allergic rhinitis and nonspecific bronchial responsiveness has produced conflicting results. In fact, some studies showed a strong correlation and other failed to find an association. However, little is known about the effect of natural specific allergen exposure on the bronchial reactivity of mono-sensitive patients with rhinitis in the southern Mediterranean area, in relation to skin reactivity to allergens, total serum IgE levels and blood eosinophiis. Objectives The significance of the association between allergic rhinitis, and abnormal airway responsiveness with regard to the pathogenesis of asthma is unclear. For this reason, we have studied non-specific bronchiai hyperreactivity. in patients with seasonal allergic rhinitis, with reference to the responsible allergen. The aim of the study was to correlate the responsiveness to bronchoprovocation with methacholine in subjects a with allergic rhinitis during and out of the pollen season with total serum IgE and blood eosinophils. Methods Fourty-nine non-smoking patients with clinical diagnosis of allergic rhinitis and mono-sensitive skinprick tests to pollen allergens were enrolled in the study. Twenty patients suffered from seasonal rhinitis to Parietaria pollen. 15 patients to Gramineae pollen and 14 patients to Olea pollen. In all patients lung function measurements (assessed as response to methacholine). tolal serum IgE and blood eosinophii counts were measured during and out of the pollen season. Results During pollen season. 16 out of 49 rhinitis patients demonstrated values of bronchial responsiveness measured as response to inhaled metbacholine in the asthmatic range whereas out of the pollen season only eight patients were in the asthmatic range. By analysing the results with reference to the responsible allergen, during the pollen season 5 out of 16 patients were Parietaria -sensitive and out of the pollen season seven out of eight patients. Finally, in Parietaria -sensitive rhinitis bronchial responsiveness signifi-cantly correlated, during and out of the pollen season, with total serum IgE and with blood eosinophil counts. Conclusions Our results are consistent with the hypothesis that Parietaria is more important than Olea and Gramineae as a risk for developing non- specific bronchial hyperresponsiveness. On the whole, present observations provide further evidence that there is an interrelationship of allergen kind, total serum IgE. eosinophil and bronchial hyperressponsiveness suggesting that they may play a role in the development of bronchial asthma in rhinitis patients.     

A multicentre study assessing the prevalence of sensitizations in patients with asthma and/or rhinitis in China

Background: The prevalence of sensitization in patients with asthma and rhinitis in mainland China remains unclear. Objective: Our aim was to estimate the prevalence of allergy in patients with respiratory allergic diseases such as asthma and/or rhinitis attending respiratory clinics within mainland China. The study also investigated regional and annual differences in the prevalence and pattern of sensitization among the patients in China. Method: A cross‐sectional survey was performed in 6304 patients suffering from asthma and/or rhinitis in 17 cities from 4 regions of China. Patients completed a standardized questionnaire asking for the presence of respiratory and allergic symptoms. They also underwent skin prick tests with 13 common aeroallergens. Results: Among the 6304 patients, 4545 (72.1%) had at least one positive skin prick reaction. The overall prevalence of positive skin prick responses was 59.0% for Dermatophagoides farinae, 57.6% for Dermatophagoides pteronyssinus, 40.7% for Blomia tropicalis, 16.1% for American cockroach, 14.0% for dog, 11.5% for Blatella germanica, 11.3% for Artemisia vulgaris, 10.3% for cat, 6.5% for Ambrosia artemisifolia, 6.3% for mixed mould I, 4.4% for mixed mould IV, 3.5% for mixed grass pollen and 2.2% for mixed tree pollen. Sensitizations to common allergens varied widely between geographical areas and demonstrated unique pattern in patients by stratification with age groups, with asthma and/or rhinitis. Severity of rhinitis and asthma was significantly correlated with skin index of reactivity to Artemisia vulgaris, Ambrosia artemisifolia and to D. pteronyssinus, D. farinae and Blomia tropicalis respectively (P < 0.001). Positive reactivity to the tested allergens and concomitant reactivity to multiple allergens including to house dust mites and Blomia tropicalis was markedly increased in patients with both asthma and rhinitis. Conclusion: House dust mites were the most prevalent allergens in patients with asthma and/or rhinitis in China. There were significant differences in patterns of sensitizations in patients from different geographical areas, age groups as well as asthma and/or rhinitis.