Impact of individual molecular components in determining primary sensitization to latex.

Allergy to natural rubber latex emerged as one of the main allergies at the beginning among some professional groups and the general population. Sensitization and development of latex allergy have been attributed to exposure to products containing residual latex proteins. The prevailing cross-reactivity of latex proteins with other food allergens is of great concern. Numerous purified allergens are currently available, which greatly help in patient management, thus determining their specific profile. We conducted a multicenter study to investigate changes, from the ROC analysis, in the characteristics of patients with latex allergy by measuring its major protein components. Sensitization to latex proteins is crucial because it highlights the cross reactivity to inhalants (pollen) and food (fruit). It is very essential in an accurate and specific clinical setting.

Profiles of Birch Sensitization (Bet v 1, Bet v 2, and Bet v 4) and Oral Allergy Syndrome Across Italy.

BACKGROUND: Birch allergy (BA) is a common pollinosis caused by the allergens Bet v 1, Bet v 2, and Bet v 4. Oral allergy syndrome (OAS) is frequently associated with BA. A gradient of sensitization to birch allergen across Europe has been reported. Therefore, this study aimed to investigate the birch sensitization profile, including OAS, across Italy. METHODS: We performed a retrospective study of 854 patients (391 males, mean age 35.9 years, range 18-93 years): 196 patients were recruited in Genoa, 188 in northern Italy, 359 in central Italy, and 111 in southern Italy. Serum IgE to Bet v 1, Bet v 2, and Bet v 4 was assessed, and OAS was analyzed. RESULTS: With respect to the geographical path Genoa-North-Center-South, the frequency of sensitization to Bet v 1 decreased significantly (P<.0001) from Genoa (95.41%) to southern Italy (58.56%). The frequency of sensitization to Bet v 2 increased significantly (P<.0001) from Genoa (6.12%) to southern Italy (52.25%). The frequency of Bet v 4 also increased significantly (P=.0002) from Genoa (6.12%) to southern Italy (14.41%). The distribution of patients with OAS differed significantly across the areas (P<.0001), the most marked difference ranging between 33.5% in Genoa and 76.9% in northern Italy. The frequency of birch allergens correlated with OAS in central Italy only. CONCLUSIONS: The present study demonstrated a significant difference between sensitization to birch and its clinical expression across Italy.

Profiles of birch Sensitization (Bet v 1, Bet v 2, and Bet v 4) and oral allergy syndrome acrsss Italy

Background: Birch allergy (BA) is a common pollinosis caused by the allergens Bet v 1, Bet v 2, and Bet v 4. Oral allergy syndrome (OAS) is frequently associated with BA. A gradient of sensitization to birch allergen across Europe has been reported. Therefore, this study aimed to investigate the birch sensitization profile, including OAS, across Italy. Methods: We performed a retrospective study of 854 patients (391 males, mean age 35.9 years, range 18-93 years): 196 patients were recruited in Genoa, 188 in northern Italy, 359 in central Italy, and 111 in southern Italy. Serum IgE to Bet v 1, Bet v 2, and Bet v 4 was assessed, and OAS was analyzed. Results: With respect to the geographical path Genoa-North-Center-South, the frequency of sensitization to Bet v 1 decreased significantly (P<.0001) from Genoa (95.41%) to southern Italy (58.56%). The frequency of sensitization to Bet v 2 increased significantly (P<.0001) from Genoa (6.12%) to southern Italy (52.25%). The frequency of Bet v 4 also increased significantly (P=.0002) from Genoa (6.12%) to southern Italy (14.41%). The distribution of patients with OAS differed significantly across the areas (P<.0001), the most marked difference ranging between 33.5% in Genoa and 76.9% in northern Italy. The frequency of birch allergens correlated with OAS in central Italy only. Conclusions: The present study demonstrated a significant difference between sensitization to birch and its clinical expression across Italy (AU)

Introducción: El síndrome de alergia oral (SAO) se encuentra frecuentemente asociado a la alergia al polen de abedul. Se han descrito diferentes gradientes de sensibilización a polen de abedul en Europa. Este estudio pretende determinar el perfil de sensibilización a polen de abedul, incluyendo la presencia de SAO, en Italia. Métodos: Estudio retrospectivo con 854 pacientes (391 hombres, edad media 35,9 años, rango 18-93 años): 196 pacientes procedían de Génova, 188 del Norte de Italia, 359 de Italia Central y 111 del Sur de Italia. Se determinó la IgE específica a Bet v 1, Bet v 2 y Bet v 4, así como la presencia de SAO. Resultados: De acuerdo a la procedencia geográfica Génova-Norte-Centro-Sur de Italia, la sensibilización a Bet v 1 disminuye significativamente (P<0,0001) desde Génova (95,41%) hasta el Sur de Italia (58,56%). La sensibilización a Bet v 2 aumenta significativamente (P<0,0001) desde Génova (6,12%) hasta el Sur de Italia (52,25%). También la sensibilización a Bet v 4 aumenta significativamente (P<0,0002) desde Génova (6,12%) hasta el Sur de Italia (14,41%). Existe una distribución del SAO significativamente diferente entre las diferentes áreas geográficas consideradas, siendo la máxima diferencia la presentada entre Génova (33,5%) y el Norte de Italia (76,9%). Las frecuencias de sensibilización a las diferentes moléculas del polen de abedul se correlacionan con el SAO solo en la región Central de Italia. Conclusiones: El presente estudio demuestra la existencia de diferencias significativas entre la sensibilización a las diferentes moléculas del polen de abedul y su expresión clínica en diferentes regiones italianas (AU)

A study of HLA class I and class II 4-digit allele level in Stevens-Johnson syndrome and toxic epidermal necrolysis.

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are represented by rare but life-threatening cutaneous adverse reactions to different drugs. Previous studies have found that in a Han Chinese population from Taiwan and other Asian Countries, a strong genetic association between HLA-class I alleles (B*15:02, B*58:01) and SJS and TEN was induced by carbamazepine and allopurinol, respectively. To identify genetic markers that covered the MHC region, we carried out a case-control association enrolling 20 Caucasian patients with SJS/TEN. Our patient series included 10 cases related to paracetamol, 7 to allopurinol and 3 to different drugs (plaquenil, itraconazol, nabumetone). Healthy controls were represented by 115 Caucasian bone marrow or stem cell donors. The HLA-A*, B*, C*, DRB1*, DQB1*, DQA1* and DPB1* genotyping were determined. The frequencies of HLA-A*33:03 as well as C*03:02 and C*08:01 were significantly higher in SJS/TEN patient subgroup showing allopurinol drug-induced severe cutaneous adverse reactions (SCAR) as compared to controls (28.6% vs 0%, P=0.00002, Pc=0.0011; 28.6% vs 0%, P=0.00002, Pc=0.001; 28.6% vs 0%, P=0.00002, Pc=0.001, respectively). In the same subgroup the frequencies of B*58:01, DRB1*15:02 and DRB1*13:02 alleles, although considerably higher than in control group (42.8% vs 5.2%, P=0.003; 28.6% vs 1.7%, P=0.005; 28.6% vs 3.5%, P=0.037, respectively), appeared no more statistically different after P correction (Pc=0.248; Pc=0.29; Pc=1.00, respectively). In addition, in 10 of the 20 SJS/TEN patient subgroup with paracetamol-induced SCAR no statistically significant association with HLA alleles could be found. However, in the same SJS/TEN patient subgroup showing allopurinol drug-induced SCAR, haplotype analysis indicated that B*58:01, DRB1*13:02 and DRB1*15:02 alleles, that in a single allele analysis lost statistical significance after P correction, may still confer susceptibility, because the B*58:01-DRB1*13:02 and DRB1*15:02-DQB1*05:02 are positively associated with the disease (14.2% vs 0.43%, P= 0.00001, Pc=0.00028; 14.2% vs 0.43%, P=0.00001, Pc=0.00028, respectively). Our results show that in contrast to SCAR-related to paracetamol, where HLA alleles do not appear to be involved, HLA molecules behave as a strong risk factor for SCAR-related to allopurinol even when a limited number of patients are considered.

Immunological cross-reactivity between lipid transfer proteins from botanically unrelated plant-derived foods: a clinical study.

BACKGROUND: Lipid transfer proteins (LTP) are highly conserved and widely distributed throughout the plant kingdom. Recent studies demonstrated immunological cross-reactivity between LTP from many botanically unrelated fruits and vegetables and concluded that LTP are pan-allergens. This study aimed to evaluate the clinical relevance of such cross-reactivity in a group of subjects monosensitized to LTP. METHODS: Twenty LTP-hypersensitive patients were selected from a population of about 600 subjects with history of Rosaceae allergy by means of: 1) negative skin prick test (SPT) with a commercial birch pollen extract; 2) positive SPT with a commercial plum extract, rich in LTP but virtually lacking both Bet v 1-like proteins and profilin; 3) in-vitro IgE reactivity to the 9-10 kDa fraction of peach peel or immunoblot with peach peel showing a single band at 10 kDa; and 4) total inhibition of reactivity to whole peach extract (containing Bet v 1-related allergen, profilin, and LTP) by purified peach LTP on enzyme-linked immunoassay (ELISA). Allergy to foods other than Rosaceae was ascertained by careful interview and analysis of medical recordings. SPT with a large series of plant-derived foods were carried out as well. The cross reactivity between LTPs from botanically unrelated plant-derived foods was assessed by ELISA inhibition tests using walnut and peanut extracts as substrate, and peach LTP as inhibitor. RESULTS: All patients reported allergic reactions after the ingestion of at least one from a large number of vegetable foods other than Rosaceae, and in several cases clinical reactions were very severe (anaphylaxis, asthma, urticaria/angioedema). Nuts and peanuts were the most frequently reported causes of allergic reactions (80% and 40% of patients, respectively). All patients showed positive SPT to several non-Rosaceae food extracts. SPT with nuts, peanut, legumes, celery, rice, and corn were positive in the majority of patients. In ELISA inhibition studies, absorption of sera with peach LTP caused complete inhibition of IgE reactivity to walnut and peanut in all cases. CONCLUSION: LTP is a clinically relevant pan-allergen. Most Rosaceae-allergic, LTP-hypersensitive patients experience adverse reactions after ingestion of botanically unrelated plant-derived foods as well. In view of the high prevalence and severity of the allergic reactions induced, hazelnut, walnut, and peanut should be regarded as potentially hazardous for these patients.

[Diagnosis of food allergy and IgG4]. / Diagnosi di allergia alimentare e IgG4.

We compared specific IgG4 levels in a group of children with food allergy and in an healthy control group. The results show no significant differences in the values of specific IgG4 levels between the two groups of children.