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In a 2-year double-blind placebo controlled study an immunological evaluation was carried out on 33 patients (15 males, 18 females, mean age 29.2 years) with mite-induced perennial rhinitis who were submitted to specific immunotherapy (IT) with an alginate-conjugated extract of D. pteronyssinus. The behaviour of IgE, IgG, IgG1 and IgG4 antibodies specific to D. pteronyssinus and its major allergen Der p1 was characterized by assessment of their changes in serum, and changes in IgG in nasal secretions during the treatment. The placebo-treated patients did not show any significant variation in the levels of specific antibodies, while in the actively treated patients we found: a statistically significant decrease (P less than 0.005) of specific IgE, a statistically significant increase of specific IgG (P less than 0.005), IgG1 (P less than 0.005) and IgG4 (P less than 0.005) in serum and a statistically significant increase (P less than 0.001) of specific IgG in nasal secretions. The IgG response showed an early relative predominance of the IgG1 subclass and a late absolute predominance of IgG4 subclass, that confirmed the model of IgG4 restriction in prolonged allergen stimulation. No correlation was found between immunological and clinical data.

Twenty-eight subjects affected by perennial asthma were selected in order to investigate the possibility of inducing or relieving an asthmatic attack by means of suggestion. Twenty-five were positive to methacholine challenge test and, among them, eleven reacted to an ultrasonic nebulized distilled water test. The effect of suggestion on airway response was assessed by eight inhalations of normal saline at 32 degrees C alternately presented as a bronchoconstrictor or as a bronchodilator drug. Eight inhalations of the same diluent without any psychic stimulus were used as control test. Seven patients reacted with bronchoconstriction to both positive and negative suggestion and to control test. Further, this group of patients showed a lower methacholine PD20 when compared with the other subjects. In this study, the effects of suggestion on bronchial reactivity were not observed and bronchoconstriction belonged to an individual hyperreactivity of the airways.

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.

A randomized population of 222 beekeepers from Lombardy (203 males, 19 females, of mean age 42.5 years) was studied to determine the frequency of allergic reactions to bee sting. The type of reactions, the clinical evolution at the subsequent stings and the risk factors concerning the development of allergy (presence of venom specific IgE, number of stings in a year, atopy, age) were evaluated. It was found that 170 beekeepers never presented reactions to stings while 52 (23.4%) showed allergic reactions consisting in 31 large local reactions and 21 systemic reactions; of these, 3 (5.7%) were life-threatening. In the group of beekeepers with allergic reactions at the subsequent stings, 26 (50%) showed a spontaneous loss of reactivity, 16 (30.8%) presented persistent, but unchanged in severity, reactions and 10 (19.2%) had a worsening of symptoms. Specific honey bee venom IgE levels (measured by means of RAST) were significantly lower in immune beekeepers when compared with the group with allergic reactions (p less than 0.01) and in beekeepers with previous allergy when compared to the ones with persistent reactions (p less than 0.05). We also found significant differences about the number of stings received in a year by beekeepers with persistent allergic reactions (17.5 stings), beekeepers with previous allergy (89.8 stings) and immune subjects (126.9 stings). On the contrary, no significant differences were detected about the age and the presence of atopy. These results suggest that practice of bee-keeping induces a relatively high incidence of allergic reactions but with a trend to the spontaneous improvement of symptoms and a low incidence of severe reactions.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

We studied 52 children, 3 to 15 years of age, suffering from allergic reactions following Hymenoptera stings. The diagnosis of allergy was based on history, results of skin tests and RAST performed by purified venoms of Apis mellifera, Vespula species and Polistes species. The history of children with multiple stings of the same insect showed an essential favourable prognosis, thus suggesting to submit to specific immunotherapy only children with severe reactions. For these patients it is necessary to perform therapy only in specialized Centres, because of the high frequency of adverse reactions which we observed in 33% of our treated patients.

Monolateral or bilateral anophthalmos recurring in the absence of other associated defects in six members of a family is reported. The malformation appears to be inherited as a dominant (autosomal or X-linked) trait with incomplete penetrance. Implications for genetic counselling are briefly discussed.

To determine the diagnostic value and precision of the quantitative skin test (QST), RAST, specific nasal (NPT) and conjunctival (CPT) provocation tests, we studied 91 patients, suffering from allergic rhinoconjunctivitis with positive skin prick tests (SPT) to common allergens, among whom sixty-nine of them had symptoms related to the positive SPT, and 22 had no clinical correspondence. In these two groups, by comparing the threshold of positivity, we investigated whether there was any parallelism between responses to the tests considered. We also compared the level of specific IgE (RAST) to the wheal-areas evoked by preliminary SPT for the corresponding allergen in order to detect any quantitative relationship between these investigations. Increasing concentrations of standardized allergen extracts (from 10 to 100,000 BU/ml) were used in all in vivo tests. NPT was evaluated on the basis of multiple recordings of nasal resistances by anterior passive rhinomanometry. QST proved to correlate well with RAST and its easier method ensures it a major role in assessing the levels of allergic sensitization. SPT wheal-areas and RAST vales correlated well only for grass and birch, presumably because of better standardization of these allergen extracts. When provocation tests, especially NPT, were positive, patients were almost always symptomatic for the allergen tested (high positive predictive value). Likewise, 21 out of the 22 asymptomatic subjects had negative NPT (high specificity). These results suggested the utility of standardized provocation tests in order to restrict diagnosis to the truly causative allergens in patients with multiple positive SPT results.

The aim of the study was to check whether, after a period of complete exclusion of the offending foods in adult subjects suffering from food allergy, these foods could subsequently be safely reintroduced into the diet. Patients with chronic urticaria and/or perennial rhinitis negative for secondary pathology or other allergies were subjected to a strict diagnostic protocol for food allergy. Briefly, out of a case list of 207 patients, we found 23 patients whose symptoms were clearly related, on open reintroduction, to at least one food. The really offending foods in these patients were subsequently identified by double-blind, placebo-controlled food challenges. Only 10 of the 23 patients had positive challenges for 13 foods. Double-blind challenges were repeated after 1 year or more of avoidance of the offending foods to evaluate the persistence or disappearance of sensitivity. We found that five (38%) of the 13 previously offending foods were well tolerated. Thus, in adults, as previously proved in children, dietary avoidance of the offending foods appears to be an effective measure for dealing with food allergy. The kind of foods involved and the completeness of their avoidance appeared to be important factors favoring the reestablishment of tolerance in adults.