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Biomedical subjects

R Asero

Publications and source records attributed to R Asero.

At least 73 records · Page 4Linked to original sources
PubMed1999

Detection and clinical characterization of patients with oral allergy syndrome caused by stable allergens in Rosaceae and nuts.

BACKGROUND: A minority of patients with oral allergy syndrome (OAS) induced by Rosaceae or nuts are positive on skin prick tests with commercial food extracts. This suggests reactivity against distinct stable allergens. OBJECTIVES: (1) To define the prevalence of subjects positive on skin prick tests with commercial extracts among patients with OAS caused by Rosaceae and/or nuts and (2) To investigate whether commercial extracts-positive subjects show some peculiar clinical feature and may represent a specific subset with food allergy. METHODS: Skin prick tests were carried out with a large panel of commercial extracts of airborne allergens (Allergopharma) and of vegetable foods (Dome/Hollister-Stier) in 298 adults with OAS caused by Rosaceae (n = 237) and or nuts (n = 161), positive on skin prick tests with fresh offending foods. RESULTS: 25/237 (11%) patients were positive on prick tests with commercial plum extract. This subgroup showed a higher incidence of systemic symptoms (64% versus 6%; P < .001) and a lower incidence of birch pollen allergy (12% versus 99%; P < .001) than commercial extract-negative patients; moreover, 36% versus 0%, respectively, did not have respiratory allergy (P < .001). Apple and peach were the main offending foods among commercial extract-negative and commercial extract-positive patients, respectively (87% versus 44% for apple, P < .001; and 52% versus 88% for peach, P < .005). Eight of one hundred sixty-one (5%) nuts-sensitive patients were positive on prick test with commercial walnut extract. This subgroup showed a higher proportion of patients who experienced systemic symptoms (63% versus 6%, P < .001), a lower prevalence of birch pollen allergy (13% versus 97%, P < .001), and a higher prevalence of grass pollen allergy (88% versus 41%, P < .05) than commercial extract-negative subjects. Further, reactivity against commercial walnut extract was associated with skin reactivity against commercial extracts of peanut (88% versus 37%, P < .005), tomato (75% versus 5%, P < .001), and plum (63% versus 8%, P < .001), and inversely related with skin reactivity against fresh apple (P < .001). In most cases, high levels of IgE specific for peach, apple, and hazelnut were associated with peanut reactivity rather than with clinical sensitivity to specific foods. In a preliminary investigation, most commercial extract-positive patients reacted against a 10-kDa protein characterized as a lipid transfer protein (LTP). CONCLUSIONS: Skin prick tests with commercial extracts of plum and walnut may be usefully employed to detect patients with OAS reacting against stable allergens. The high prevalence of systemic symptoms in these patients suggests that allergens' stability is associated with a higher resistance to the gastrointestinal environment and strongly influences the clinical expression of vegetable food allergy. At least some stable allergens, namely lipid transfer protein might be shared by botanically unrelated fruits such as nuts, peanuts, legumes, tomato, and Prunoideae.

Adult↗
PubMed1999

Risk factors for acetaminophen and nimesulide intolerance in patients with NSAID-induced skin disorders.

BACKGROUND: Previous studies show skin reactions after exposure to acetaminophen and/or nimesulide to occur in about 10% of patients with a history of urticaria induced by aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs). This fact is surprising since cross-reactivity among different NSAIDs should not occur among subjects without a history of chronic urticaria. OBJECTIVE: To detect risk factors for intolerance to alternative drugs such as acetaminophen and nimesulide in different groups of patients with a history of adverse skin reactions (urticaria/angioedema, or anaphylaxis) after the ingestion of aspirin and other NSAIDs. METHODS: Two hundred fifty-six patients with a history of recent pseudoallergic skin reactions caused by NSAIDs underwent elective oral challenges with increasing doses of both acetaminophen and nimesulide. Patients were divided into three groups: A = 69 subjects with chronic urticaria, B = 163 otherwise normal subjects with a history of urticaria after the ingestion of aspirin, and C = 24 otherwise normal subjects with a history of urticaria after the ingestion of pyrazolones but aspirin-tolerant. RESULTS: Forty-eight (19%) patients reacted to acetaminophen and/or nimesulide. Similar numbers of patients with chronic urticaria (23%) and of normal subjects with a history of aspirin-induced urticaria (19%) did not tolerate one of the alternative drugs challenged. Pyrazolones-intolerant patients showed the lowest number of reactors (4%). Aspirin intolerance represented a risk factor for acetaminophen- and/or nimesulide-induced urticaria (RR = 5.4). A history of anaphylactoid reactions induced by NSAID represented a risk factor for urticaria after the ingestion of the alternative study drugs (RR = 5.7). Atopic status was associated with a higher risk of reactivity to nimesulide: this drug induced urticaria in 11/47 (23%) atopics versus 18/209 (9%) non-atopics (P < .005; RR = 3.2). A history of intolerance to antibacterial drugs was not associated with a higher prevalence of reactivity against acetaminophen and/or nimesulide. CONCLUSIONS: In at least 20% of patients with a history of urticaria/angioedema or anaphylaxis induced by aspirin or other NSAIDs, but without a history of chronic urticaria, cross-reactivity with other NSAIDs occurs. Atopy as well as a history of aspirin-induced anapylactoid reactions seem to represent relevant risk factors for intolerance to alternative NSAIDs. In view of these findings, aspirin-intolerant patients with such clinical features should be submitted to peroral tolerance tests with at least two alternative substances in order to avoid potentially severe reactions.

Acetaminophen↗
PubMed1998

Aspirin and paracetamol tolerance in patients with nimesulide-induced urticaria.

BACKGROUND: The administration of aspirin and other nonsteroidal anti-inflammatory drugs in patients sensitive to nimesulide might be hazardous. OBJECTIVE: To assess the tolerance to both acetaminophen (paracetamol) and aspirin in patients with a history of urticaria induced by nimesulide. METHODS: Nine patients with a history of nimesulide intolerance were submitted to single-blind, placebo-controlled peroral challenges with increasing doses of acetaminophen and aspirin. RESULTS: Acetaminophen was tolerated by all patients, whereas two experienced immediate systemic urticaria after the administration of 125 mg of aspirin. CONCLUSION: Acetaminophen and aspirin are well tolerated by most nimesulide-sensitive patients. Since a minority of patients show aspirin sensitivity, tolerance of this agent should always be ascertained by properly performed peroral challenges.

Acetaminophen↗
PubMed1998

Detection of patients with multiple drug allergy syndrome by elective tolerance tests.

BACKGROUND: Multiple drug allergy syndrome (MDAS) caused by antibiotics is frequently observed in allergy departments; however, risk factors for such a condition as well as the means to detect patients prone to MDAS are poorly defined. OBJECTIVE: The identification of patients prone to MDAS and the detection of risk factors for multiple antibiotic sensitivity. METHODS: Two hundred fifty-three elective oral challenges with alternative antimicrobial drugs were performed in 120 patients with histories of recent allergic reactions to antibiotics. RESULTS: Twenty-three (19%) subjects reacted to at least one antibiotic class. All reactions were mild and easily controlled by conventional therapy. Female sex, history of multiple antibiotic reactions, and reactions to nonsteroidal antinflammatory drugs were the main risk factors for reactions to alternative antibiotics. To date, no patient has reported immediate adverse reactions to drugs negative on oral challenge tests but one had urticaria/angioedema on the fifth day of full dose treatment with ofloxacin. CONCLUSIONS: Elective oral challenges with alternative antibiotics are a sensitive, specific, and safe means to detect patients with MDAS, thus sparing them more severe adverse reactions caused by full dose therapies. The recommendation to perform oral challenge tests with antibiotics just before their therapeutic use seems unnecessary and should be reconsidered.

Administration, Oral↗
PubMed1998

Effects of birch pollen-specific immunotherapy on apple allergy in birch pollen-hypersensitive patients.

BACKGROUND: Most patients with birch pollen allergy report oral allergy symptoms after eating fresh apples and other vegetable foods. Major birch pollen and apple allergens, Bet v 1 and Mal d 1, are highly homologous; as a consequence, pollen-specific immunotherapy (SIT) might be expected to improve apple hypersensitivity. OBJECTIVE: To evaluate the clinical and immunological effects of birch pollen SIT on oral allergy syndrome (OAS) induced by apples. METHODS: A prospective study carried out in 49 birch pollen-sensitive patients with apple-induced OAS who received injection immunotherapy for 12, 24, or 36 months. Twenty-six patients not submitted to SIT and followed up for 12-48 months were used as controls. Both SPT and open oral challenges with fresh golden delicious apple were performed, as well as specific IgE measurements, before and after SIT. RESULTS: Forty-one patients (84%) vs no control (0%) reported a significant reduction (50-95%) or a total disappearance (100%) of OAS symptoms after SIT (P < 0. 001). Similar responses were observed in patients treated for 12, 24, or 36 months. SIT also induced a marked reduction in skin reactivity against fresh apple in 43 patients (88%). The effect of SIT was inversely related with baseline skin reactivity: 50% and 8% patients with a weakly or strongly positive baseline apple skin prick tests (SPT), respectively, did not report changes in OAS severity after SIT (P < 0.01). In contrast, baseline birch pollen-specific or apple-specific IgE antibodies levels did not influence SIT effectiveness on OAS. SIT induced a marked decrease in birch pollen-specific IgE levels (P < 0.001), whereas apple-specific IgE showed an unexpected variability (reduction in 21%, no change in 43%, increase in 38%). No control subject reported a reduction in OAS severity or showed a decrease in skin reactivity at follow-up (P < 0.001). CONCLUSIONS: SIT with birch pollen extracts effectively reduces clinical apple sensitivity and skin reactivity in most cases after only 1 year of treatment; these effects are not paralleled by a similar reduction in apple-specific IgE. These findings suggest a decrease in activability of effector cells as the mechanism underlying clinical benefit.

Adult↗
PubMed1997

Relevance of pollen-specific IgE levels to the development of Apiaceae hypersensitivity in patients with birch pollen allergy.

A large clinical/serologic study was carried out to determine the prevalence of Apiaceae (carrot, celery, and fennel) hypersensitivity in patients with birch pollen allergy, and to investigate its relationship with apple and hazelnut allergy and with birch pollen-specific IgE levels. A total of 196 birch pollen-hypersensitive patients with oral allergy syndrome (OAS) caused by different vegetable foods were examined in the cross-sectional part of the study. Of this total, 195 patients had apple and/or hazelnut allergy, and 103 had Apiaceae sensitivity; only one patient had Apiaceae allergy alone. Apiaceae-positive patients showed significantly higher birch pollen-specific IgE levels than negative ones (median 13 vs 7 AU/ml; P < 0.0001). The prospective part of the study was performed on 103 birch pollen-hypersensitive patients who were OAS-free at the time of the first visit and were periodically followed-up for OAS. Patients who developed Apiaceae sensitivity showed much higher birch-specific IgE levels than patients who developed apple/hazelnut allergy only (median 15.5 vs 8.5 AU/ml; P < 0.05), whereas those who remained OAS-free showed the lowest specific IgE levels (median 5 AU/ml). This study suggests that most Apiaceae determinants cross-react with apple or hazelnut determinants, whereas only some apple or hazelnut determinants cross-react with Apiaceae-allergenic determinants; moreover, it shows that birch-specific IgE levels heavily influence the onset of OAS as a whole, and probably play a critical role in the development of allergies to distinct vegetable foods as well.

Adolescent↗
PubMed1996

Detection of prognostic factors for oral allergy syndrome in patients with birch pollen hypersensitivity.

To determine why a significant proportion of birch pollen-sensitive patients do not have the oral allergy syndrome (OAS), possible predictive in vivo or in vitro tests for OAS were sought in a large retrospective and prospective follow-up study performed in 283 patients with clinical evidence of birch pollen hypersensitivity. OAS was associated with more severe respiratory symptoms and with higher birch-specific and total IgE levels; moreover, its onset was clearly related to duration of birch pollinosis. The prospective part of this study, performed in 63 patients without OAS, confirmed these findings and highlighted the very high negative predictive value of both skin prick tests with fresh foods and RAST with food allergens. This work suggests that about 15% of patients with birch pollen hypersensitivity are not prone to OAS and that their anti-birch IgE might be directed against determinants that do not crossreact with food allergens.

Adolescent↗