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E A Pastorello

Publications and source records attributed to E A Pastorello.

58 records · Page 4Linked to original sources

Allergen specific IgG subclass antibody response in hyposensitization with Dermatophagoides pteronyssinus extract.

Most of the controlled trials of specific immunotherapy (SIT) with house dust mite showed a good clinical efficacy of different kinds of extract after variable periods of treatment. However, few of them looked at all the parameters available to monitor this therapy, such as threshold dose of specific provocation test, end point titration and immunological variations. In particular, the behaviour of specific IgE antibodies is not completely known, while, in more recent studies, mite specific IgG antibodies have been shown to increase even in the early stages of treatment. Few data are available on mite specific IgG1-4 subclasses. The preliminary results of a double blind placebo controlled trial we performed with alginate conjugated Dermatophagoides pteronyssinus extract seem to indicate a good clinical and immunological response to this kind of extract. Moreover, we observed a significant increase of specific IgG antibodies, total and subclasses IgG1.2.4, with a prevalence of IgG4 subclass after three months of SIT. After two years of SIT mite specific IgG1 antibodies showed a tendency to decrease, while IgG4 antibodies maintained a constantly high level.

Animals↗

IgG subclass antibody response to hymenoptera venom.

Venom immunotherapy provides clinical protection against hymenoptera stings in almost all treated allergic patients. Venom specific IgG antibodies often rise during immunotherapy and some studies found an association between their levels and clinical protection in subjects treated with Yellow Jacket venom. It is interesting to report that, among IgG subclasses, venom specific IgG4 show the most significant increase but IgG1 could represent a relevant immunological mechanism, exerting a regulatory function on venom specific IgE levels. We observed in patients submitted to Honey Bee venom immunotherapy a significant increase of venom specific IgG1 and IgG4 antibodies, while IgG2 showed an insignificant increase only in some patients. Persistent high levels of IgG4 with respect to decreasing levels of IgG1 were observed only after prolonged treatment.

Antigen-Antibody Reactions↗

Are double-blind food challenges necessary before starting an elimination diet?

Food allergy is normally treated by eliminating the offending food. Such a measure, however, may cause nutritional and sociopsychological problems, so an allergy must be diagnosed with the utmost certainty. To date the most reliable diagnostic test is the double-blind food challenge (DBFC). The rationale for using this test is the marked difference in positive results with open and double-blind food challenges. Only about 30% of open challenges that appear positive are confirmed on blind challenge. There is ample evidence, too, that a negative DBFC may in fact indicate tolerance to that food. From the literature it appears that almost all patients who reintroduced a certain food into their diet after a DBFC had given negative findings did not present any adverse reaction to it. In our caselist of 21 patients with probable reactions to foods but negative DBFC, 19 (90.5%) tolerated the "incriminated" food well when it was reintroduced into their diet even in unlimited amounts. Only two (9.5%) again presented symptoms when they started taking large amounts of the problem food. Therefore, one precaution recommended before reintroducing a food item into a patient's diet after a negative DBFC is to check how it is tolerated at high doses. A review of the literature confirms the unquestioned utility of the DBFC. Nevertheless, in some situations this test is not indicated. The main one, of course, is in patients with life-threatening symptoms such as anaphylactic shock or glottis edema, in whom any provocation test is contraindicated.(ABSTRACT TRUNCATED AT 250 WORDS)

Diet↗

Importance of allergic etiology in nasal polyposis.

Sensitization to environmental allergens in nasal polyposis was evaluated in an in vitro study conducted on 90 patients undergoing polypectomy by measuring total and specific IgE for a panel of common allergens and levels of IgG, IgA and albumin in serum, and nasal secretions (NSe). Fifty healthy individuals were chosen as a control group. Total IgE concentrations were higher in patients with nasal polyps than in controls. RAST was positive in serum in 34 (38%), in NSe in 29 (32%), and exclusively in NSe in 10 patients (11%). Allergens most frequently involved were mites and cat dander. No differences were found between the study and control groups for serum and NSe IgA, albumin, and serum IgG, whereas IgG in NSe were significantly higher in patients with nasal polyps. Subjects with positive RAST only in NSe had significantly lower secretory IgA than did controls. Our data indicate that in nasal polyposis: 1) sensitization to aeroallergens is relatively common; 2) a local production of specific IgE may occur, especially for perennial allergens; 3) prolonged exposure to these allergens gives rise to chronic nasal inflammation, with altered local production of immunoglobulins.

Adolescent↗