Two cases of elevated tryptase in abdominal aortic aneurysm.

INTRODUCTION: From the literature, patients with a history of anaphylaxis to hymenoptera venom and positive specific IgE have shown a correlation between elevated tryptase levels and two clinical situations: systemic mastocytosis and an increased risk of reactions to venom immunotherapy or hymenoptera sting. Other clinical scenarios could explain elevated tryptase levels. MATERIAL AND METHODS: A 67 year old male (P1) and a 77 year old male (P2) were evaluated for previous severe anaphylaxis to hymenoptera sting. They underwent standard diagnostic work-up for hymenoptera venom allergy. Having found elevated tryptase levels, these were followed by a bone marrow biopsy to rule out systemic mastocytosis. RESULTS: P1: specific IgE and skin tests were positive for Vespula species; tryptase 52.8 ng/ml; P2: specific IgE and skin tests were positive for Vespa cabro and tryptase 153 ng/ml. Bone marrow biopsy results were negative for mastocytosis. We carried out magnetic resonance imaging, in P1 to better characterize the severe osteoporosis and in P2 because during physical examination a pulsating mass had been identified in the mesogastrium, and an aneurysm of the abdominal aorta which required surgical intervention in both patients was detected. Eight months after surgery, tryptase levels had diminished significantly (P1: 11.6 ng/ml and P2: 14.5 ng/ml). DISCUSSION: The elevated tryptase levels were correlated to abdominal aneurysm in both patients. In fact, post-surgery tryptase levels dramatically decreased. These two cases demonstrate that high tryptase levels in subjects with a history of hymenoptera venom anaphylaxis can be associated to undiagnosed aneurysmatic disease.

Meat allergy: I--Specific IgE to BSA and OSA in atopic, beef sensitive children.

OBJECTIVE: The use of lamb meat products has been suggested as an alternative diet for polyallergic children, although until now this clinical practice has not been supported by in-depth biochemical/immunological studies. The aims of this research were: to evaluate cross-reactivity between lamb and beef; to evaluate the role of BSA and OSA as allergens in beef allergic children; and to evaluate cross-reactivity between BSA and OSA. METHODS: 16 children suffering from atopic dermatitis (AD), aged 12 months-8 8 years (mean age 2.61 +/- 1.93 years) were found skin prick test (SPT)--positive to bovine meat; all of them were also SPT-positive to ovine meat and to milk. After a period of restricted diet, the selected 16 children were recalled; 12 AD-free children (8 males and 14 females, aged 12 months-4.33 years (mean age 2.21 +/- 1.05 years) were evaluated by SPT and radioallergosorbent test (RAST) for the following allergens: bovine meat, ovine meat, BSA 1 mg/ml, OSA 1 mg/ml. Double-blind, placebo-controlled food challenge (DBPCFC) with bovine serum albumin (BSA) and ovine serum albumin (OSA) were performed. For SPT, the results were expressed in mm of wheal, and 3 mm was considered as the end point; correlation between wheal diameters was calculated by Spearman rank test. For DBPCFC, according to the Sampson's experimental procedure, BSA and OSA were given in pear juice (the dermal negative response to the pear juice was verified by fresh food SPT before starting the oral challenge test). The total dose administered to the children corresponded to the amount of albumin present in 180 g of calf or lamb meat (90 and 63 mg respectively, as calculated by Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SPS-PAGE). The administration of pear juice (containing placebo or albumin) and symptom evaluation were entrusted to medical people who did not know what the child received. RESULTS: All children tested SPT positive to bovine and ovine meat, and to BSA and OSA. Significant correlations were observed between the following diameters of wheal: BSA vs OSA (R = 0.846, p < 0.0001); ovine meat vs OSA (R = 0.769, p < 0.005); b.meat vs o.meat (R = 0.771, p < 0.005); and ovine meat vs BSA (R = 0.594, p < 0.043). In RAST, 6 of 12 children were positive to bovine meat, 3 to lamb meat, 4 to BSA and 3 to OSA. DBPCFC showed an immediate reaction to BSA or OSA in 2 and 3 children, respectively. One other child developed severe dyspnea, cough and asthma 3 hours after OSA challenge. CONCLUSIONS: BSA and OSA are important beef and lamb allergens; they share not only proteic sequences, but also allergenic properties. Clinical tolerance to BSA and OSA can be present in beef and lamb SPT-positive children.

[Allergy to Hymenoptera venom in children. Diagnosis and therapy]. / L'allergia al veleno di imenotteri in età pediatrica. Diagnosi e terapia.

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.

Activity of substance P on human skin and nasal airways.

Nasal challenge and intradermal injection with substance P (SP) were performed in five normal subjects and in five patients suffering from allergic rhinitis. No clinical symptoms, local histamine release, or modifications of nasal airway resistance were observed when SP was insufflated in the nose. Conversely, intradermal injection with SP caused a wheal and flare reaction in all the studied subjects. The different response to SP is likely to be due to the heterogeneity of human skin and nasal mucosa mast cells as far as sensitivity to histamine-releasing agents is concerned. Our findings indicate that SP has no relevant effect on human nasal mucosa, even if a synergetic action of SP with other allergic mediators cannot be excluded. The role of SP in the pathogenesis of allergic diseases in humans remains to be defined and deserves further study.

Clinical reliability of diagnostic tests in allergic rhinoconjunctivitis.

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.

[Epidemiological and clinical study on bee venom allergy among beekeepers]. / Indagine epidemiologica e clinica sull'allergia al veleno d'ape negli apicoltori.

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)

IgE-mediated food allergy.

The behaviour of some immunologic parameters was studied in order to explain the presence or the lack of symptomatology in subjects with IgE specific to foods. In particular, we compared the levels of serum and salivary IgA and IgE antibody specific to apple in 33 patients allergic to birch and with anti-apple IgE, of whom 24 had oral allergy syndrome after eating apple and nine were apple tolerants. We found no differences in the IgE-related parameters such as levels of anti-apple IgE antibody in serum and secretions, mean size of apple skin prick test, and number of patients with a positive histamine release from peripheral basophils stimulated by apple. Similarly, we detected no statistically significant differences in serum and salivary total IgG and total anti-apple IgA antibody of the two groups. We could, however, observe a significantly higher anti-apple salivary IgA/anti-apple serum IgE and anti-apple salivary IgA/anti-apple serum IgA ratios and a significant correlation between the same parameters in tolerant patients when compared with the intolerants. These results seem to suggest that the presence of appropriate levels of secretory anti-apple IgA associated to anti-apple IgE might be one of the factors playing a key role in the prevention of clinical symptoms in atopic subjects.

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.

Behavior and clinical relevance of histamine and leukotrienes C4 and B4 in grass pollen-induced rhinitis.

The release kinetics of histamine and leukotrienes C4 (LTC4) and B4 (LTB4) were investigated in nasal secretions of 10 patients with hay fever after antigen challenge. High levels of biologically active histamine were found in nasal washes from asymptomatic allergic and normal subjects. With repeated lavages, the amount of histamine recovered dropped markedly. Grass pollen challenge was followed by a significant (p less than 0.05) dose-dependent and time-limited (5 min) increase in histamine level in 7 of 10 patients; these values, however, were lower than those found in basal conditions. In 8 of 10 patients with hay fever, antigen challenge induced a significant (p less than 0.05) dose-dependent increase in LTC4 level, which persisted for 30 min. The LTC4 generation was well correlated with the appearance of allergic symptoms; LTB4 production was found in 2 patients only. A different pattern of symptoms was observed after in vivo nasal stimulation with histamine and LTC4. Histamine caused sneezing, itching, rhinorrhea, and nasal obstruction; conversely, the main symptom induced by LTC4 was a more pronounced and longer lasting nasal obstruction.

[Occurrence of drug reactions]. / Incidenza delle reazioni da farmaci.

The aim of this prospective study was to evaluate the incidence of allergic reactions to drugs compared to other kinds of medical emergencies admitted to the main Hospital in Milan during a 6 months period. At the same time we drew a list of drugs most frequently involved in allergic reactions, and a list of the most frequent symptoms. Using special forms, the medical staff collected patients' data: age, history of atopy, identification of the drug causing the reaction, and any previous reactions. Among 11,407 cases of medical emergencies, we found 163 (1.43%) patients showing drug reactions: the mean age was 27.3; 58.90% were female; atopy was present in 16.56%. The drugs most frequently involved were: pyrazon group (22%); ASA (20.86%); penicillin and derivatives (9.20%); sulfa drugs (6.14%); group B vitamins (4.30%); tetanus toxoid (4.30%); hyposensitizing extracts (3.68%); propionic acid derivatives (2.46%); paracetamol (1.84%); indomethacin (1.23%); rifampicin (1.23%); erythromycin (1.23%); glafenine (1.23%); others (17.80%). Urticaria and/or angioedema were the most frequent symptoms (86.51%), then anaphylactic shock (9.81%) and asthma (3.68%) with regard to anaphylactic shock only 6.20% of the patients had had a previous reaction to the same drug. From these data we can see that the incidence of drug reactions is very low compared to other medical emergencies; penicillin evidenced fewer reactions than expected, while the pyrazon group and ASA confirmed the data from literature.