Defoliation of common ragweed by Ophraella communa beetle does not affect pollen allergenicity in controlled conditions

Ragweed allergy is one of the primary causes of seasonal allergies in Europe and its prevalence is expected to rise. The leaf beetle Ophraella communa, recently and accidentally established in N-Italy and S-Switzerland, represents a promising approach to control ragweed, but negative side effects should be excluded before its use. Since biotic and abiotic stresses are known to influence the allergenicity of pollen, we set out to assess the effect of sub-lethal defoliation by O. communa on the quantity and quality of ragweed pollen. Seventeen sister pairs (including six clones) of ragweed plants were grown in controlled conditions. One of each pair was exposed to O. communa as soon as the plant started to produce reproductive structures. After 10 weeks of exposure, plant traits were measured as a proxy for pollen quantity. Pollen quality was assessed by measuring its viability and allergenicity. Generally, plants produced very few male flowers and little amount of pollen. Damage by the beetle was severe with most of the leaf tissue removed, but no treatment effect was found on any of the quantitative and qualitative traits assessed. In conclusion, O. communa did not increase the amount or allergenicity of ragweed pollen grains in our experimental conditions

Chronic urticaria: A focus on pathogenesis

Chronic urticaria is a spontaneous or inducible group of diseases characterized by the occurrence of wheals (and, in about half of cases, angioedema) for more than 6 weeks. These are rather frequent conditions that may severely affect patients' quality of life and sometimes represent a challenge for doctors as well. The causes of chronic urticaria are still poorly defined, although there is growing evidence that different biologic systems including immunity, inflammation, and coagulation may take part in the pathomechanism eventually leading to mast cell and basophil degranulation and hence to wheal formation. This review will discuss the main findings that are (slowly) shedding light on the pathogenesis of this disorder

Different rates of autoreactivity in patients with recurrent idiopathic angioedema associated or not with wheals

BACKGROUND: The pathophysiology and triggers of idiopathic nonhistaminergic angioedema are unclear. This study aimed to assess autoreactivity in recurrent idiopathic angioedema associated or not with wheals. METHODS: The study population comprised 19 patients with recurrent idiopathic nonhistaminergic angioedema without wheals, 38 patients with angioedema and chronic urticaria (CU), and 52 patients with CU without angioedema. Twenty healthy individuals served as controls. Autoreactivity was evaluated in vivo using the autologous serum skin test (ASST) and in vitro by measuring serum-induced basophil histamine release (BHR). RESULTS: ASST results were negative in all patients with idiopathic angioedema without wheals and in healthy controls and positive in 29 of the 38 patients with angioedema and CU (76.3%) and in 26 of the 52 patients with CU without angioedema (50%) (P < .0001 for both CU groups). BHR was negative in the healthy controls and positive in 2 of the 19 patients with idiopathic angioedema without wheals (10.5%), in 18 of the 38 patients with angioedema and CU (47.3%) (P < .0001), and in 11 of the 52 patients with CU without angioedema (21.1%) (P < .03). CONCLUSION: The different rates of autoreactivity observed in patients with idiopathic nonhistaminergic angioedema without wheals and in patients with CU either with or without angioedema suggest that these disorders have a different pathophysiology. The failure to detect circulating vasoactive factors and histamine-releasing autoantibodies explains why H1 antihistamines are scarcely effective in most patients with idiopathic angioedema without wheals. However, they represent the cornerstone of CU treatmen

Anaphylaxis related to avocado ingestion: a case and review

Anaphylaxis to avocado, independent of latex sensitization, has been rarely reported in the literature. This case report describes a 15 year old male who experienced anaphylaxis within half an hour after eating avocado-containing food. Avocado consumption is common in both North America and South America. It is important to consider avocado as a cause of anaphylaxis, even in patients not sensitized to latex

Espressione di tissue factor da parte degli eosinofili in pazienti con orticaria cronica

Sebbene numerosi casi di orticaria cronica siano attualmente considerati di origine autoimmune e associati alla presenza di autoanticorpi circolanti che inducono il rilascio di istamina, vi sono chiare evidenze sul ruolo fisiopatologico dell\u2019attivazione della coagulazione mediata dal tissue factor (TF), il principale iniziatore della cascata coagulatoria. E\u2019 stato di recente dimostrato che gli eosinofili, peraltro presenti nella cute lesionale di pazienti con orticaria cronica, sono la maggiore fonte di TF nel sangue umano. In questo studio abbiamo valutato se gli eosinofili esprimano TF nella cute lesionale di pazienti con orticaria cronica. Abbiamo studiato 20 pazienti con orticaria cronica grave, prelevando campioni bioptici cutanei da lesioni pomfoidi attive. Come gruppo di controllo sono stati utilizzati campioni di cute sana perilesionale ottenuti dall\u2019escissione chirurgica di diversi tipi di tumori cutanei (10 casi) e varie patologie cutanee caratterizzate da infiltrati usualmente privi di eosinofili, quali vasculite leucocitoclasica (7 casi), lichen planus (8 casi) e mastocitosi (3 casi). L\u2019espressione del TF \ue8 stata valutata con metodica immunoistochimica utilizzando un anticorpo monoclonale anti-TF. Sono stati inoltre eseguiti esperimenti di colocalizzazione del TF con la proteina cationica eosinofila (ECP), considerata un marcatore classico degli eosinofili, con la tecnica del doppio marcaggio mediante due anticorpi monoclonali specifici. In tutti i campioni di cute dei pazienti con orticaria cronica \ue8 stata osservata un\u2019intensa espressione del TF che era invece assente nei controlli normali (P=0.0001) e nelle malattie cutanee non eosinofilo-mediate (P=0.001-0.0001). Le indagini di doppio marcaggio per TF e ECP hanno dimostrato che le cellule positive per TF erano eosinofili. In conclusione, gli eosinofili rappresentano la principale fonte di TF nella cute lesionale di pazienti con orticaria cronica. I nostri risultati enfatizzano il ruolo di queste cellule nella fisiopatologia dell\u2019orticaria cronica fornendo il razionale per nuove strategie terapeutiche

Self‐reported drug allergy in a general adult Portuguese population

Clin Exp Allergy. 2004 Oct;34(10):1597-601. Self-reported drug allergy in a general adult Portuguese population. Gomes E, Cardoso MF, Praça F, Gomes L, Mariño E, Demoly P. Serviço de Imunoalergologia, Hospital Maria Pia, Porto, Portugal. [email protected] Abstract AIM: To estimate the prevalence of self-reported drug allergy in adults. METHODS: Cross-sectional survey of a general adult population from Porto (all of whom were living with children involved in the International Study of Asthma and Allergies in Childhood-phase three), during the year 2002, using a self-administered questionnaire. RESULTS: The prevalence of self-reported drug allergy was 7.8% (181/2309): 4.5% to penicillins or other beta-lactams, 1.9% to aspirin or other non-steroidal anti-inflammatory drugs (NSAIDs) and 1.5% to other drugs. In the group 'allergic to beta-lactams', the most frequently implicated drug was penicillin G or V (76.2%) followed by the association of amoxicillin and clavulanic acids (14.3%). In the group 'allergic to NSAIDs', acetylsalicylic acid (18.2%) and ibuprofen (18.2%) were the most frequently identified drugs, followed by nimesulide and meloxicam. Identification of the exact name of the involved drug was possible in less than one-third of the patients, more often within the NSAID group (59.5%). Women were significantly more likely to claim a drug allergy than men (10.2% vs. 5.3%). The most common manifestations were cutaneous (63.5%), followed by cardiovascular symptoms (35.9%). Most of the reactions were immediate, occurring on the first day of treatment (78.5%). Only half of the patients were submitted to drug allergy investigations. The majority (86.8%) completely avoided the suspected culprit drug thereafter. CONCLUSIONS: The results showed that self-reported allergy to drugs is highly prevalent and poorly explored. Women seem to be more susceptible. beta-lactams and NSAIDs are the most frequently concerned drugs. PMID: 15479276 [PubMed - indexed for MEDLINE

Tolerance to coxibs in patients with intolerance to non-steroidal anti-inflammatory drugs (NSAIDs): a systematic structured review of the literature

Adverse events triggered by non-steroidal anti-inflammatory drugs (NSAIDs) are among the most common drug-related intolerance reactions in medicine; they are possibly related to inhibition of cyclooxygenase-1. Coxibs, preferentially inhibiting cyclooxygenase-2, may therefore represent safe alternatives in patients with NSAID intolerance. We reviewed the literature in a systematic and structured manner to identify and evaluate studies on the tolerance of coxibs in patients with NSAID intolerance. We searched MEDLINE (1966–2006), the COCHRANE LIBRARY (4th Issue 2006) and EMBASE (1966–2006) up to December 9, 2006, and analysed all publications included using a predefined evaluation sheet. Symptoms and severity of adverse events to coxibs were analysed based on all articles comprising such information. Subsequently, the probability for adverse events triggered by coxibs was determined on analyses of double-blind prospective trials only. Among 3,304 patients with NSAID intolerance, 119 adverse events occurred under coxib medication. All adverse events, except two, have been allergic/urticarial in nature; none was lethal, but two were graded as life-threatening (grade 4). The two non-allergic adverse events were described as a grade 1 upper respiratory tract haemorrhage, and a grade 1 gastrointestinal symptom, respectively. In 13 double-blind prospective studies comprising a total of 591 patients with NSAID intolerance, only 13 adverse reactions to coxib provocations were observed. The triggering coxibs were rofecoxib (2/286), celecoxib (6/208), etoricoxib (4/56), and valdecoxib (1/41). This review documents the good tolerability of coxibs in patients with NSAID intolerance, for whom access to this class of drugs for short-term treatment of pain and inflammation is advantageous