RESUMO
Drug hypersensitivity reactions are unpredictable adverse drug reactions. They manifest either within 1-6 h following drug intake (immediate reactions) with mild to life-threatening symptoms of anaphylaxis, or several hours to days later (delayed reactions), primarily as exanthematous eruptions. It is not always possible to detect involvement of the immune system (allergy). Waiving diagnostic tests can result in severe reactions on renewed exposure on the one hand, and to unjustified treatment restrictions on the other. With this guideline, experts from various specialist societies and institutions have formulated recommendations and an algorithm for the diagnosis of allergies. The key principles of diagnosing allergic/hypersensitivity drug reactions are presented. Where possible, the objective is to perform allergy diagnostics within 4 weeks-6 months following the reaction. A clinical classification of symptoms based on the morphology and time course of the reaction is required in order to plan a diagnostic work-up. In the case of typical symptoms of a drug hypersensitivity reaction and unequivocal findings from validated skin and/or laboratory tests, a reaction can be attributed to a trigger with sufficient confidence. However, skin and laboratory tests are often negative or insufficiently reliable. In such cases, controlled provocation testing is required to clarify drug reactions. This method is reliable and safe when attention is paid to indications and contraindications and performed under appropriate medical supervision. The results of the overall assessment are discussed with the patient and documented in an "allergy passport" in order to ensure targeted avoidance in the future and allow the use of alternative drugs where possible.
RESUMO
BACKGROUND: Sensitization to common ragweed (Ambrosia artemisiifolia) is associated with a variety of risk factors, which are incompletely defined. Our aim was to evaluate the association of a variety of clinical, geographical and demographical variables with ragweed sensitization and also to determine its frequency in southern Bavaria. METHODS: In this cross-sectional multicentre study, we enrolled 977 patients with a documented or suspected atopic disease or food allergy. Data were collected on aeroallergen sensitization, age, sex, type and history of allergic disease, place of residence and potential local ragweed exposure. For this last variable, county ragweed cover was taken as a surrogate variable. Relative rates were calculated with multiple additive logistic regression models. Randomly selected patients with ragweed sensitization had a conjunctival provocation test. RESULTS: According to skin prick tests, 190 patients (19.5%) were sensitized to ragweed. The frequency of this finding increased significantly with a rising number of additional sensitizations. Other less important predictors for a ragweed sensitization were male gender, mugwort sensitization, food allergy and a maximum of complaints in September or October. County of residence, extent of local ragweed cover or type of residential area were without relevance. Of 48 sensitized patients, 26 (54.2%) had a positive conjunctival provocation test. DISCUSSION: Patients with multiple sensitizations may be more readily sensitized to a new aeroallergen. Local geographic or environmental conditions are presumably of minor importance for becoming sensitized to ragweed. The frequency of ragweed allergy among sensitized patients might be high.
Assuntos
Alérgenos/imunologia , Ambrosia/imunologia , Hipersensibilidade/epidemiologia , Pólen/imunologia , Adulto , Estudos Transversais , Feminino , Alemanha , Humanos , Hipersensibilidade/sangue , Hipersensibilidade/imunologia , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Testes CutâneosRESUMO
Fragrances are widely used in topical formulations and can cause photoallergic or phototoxic reactions. To identify phototoxic effects, 43 fragrances were evaluated in vitro with a photohaemolysis test using suspensions of human erythrocytes exposed to radiation sources rich in ultraviolet (UV) A or B in the presence of the test compounds. Haemolysis was measured by reading the absorbance values, and photohaemolysis was calculated as a percentage of total haemolysis. Oakmoss caused photohaemolysis of up to 100% with radiation rich in UVA and up to 26% with radiation rich in UVB. Moderate UVA-induced haemolysis (5-11%) was found with benzyl alcohol, bergamot oil, costus root oil, lime oil, orange oil, alpha-amyl cinnamic aldehyde and laurel leaf oil. Moderate UVB-induced haemolysis was induced by hydroxy citronellal, cinnamic alcohol, cinnamic aldehyde, alpha-amyl cinnamic aldehyde and laurel leaf oil. The phototoxic effects depended on the concentration of the compounds and the UV doses administered. We conclude that some, but not all, fragrances exert phototoxic effects in vitro. Assessment of the correlation of the clinical effects of these findings could lead to improved protection of the skin from noxious compounds.
Assuntos
Dermatite Fotoalérgica/etiologia , Hemólise/efeitos dos fármacos , Hemólise/efeitos da radiação , Perfumes/efeitos adversos , Eritrócitos/efeitos dos fármacos , Eritrócitos/efeitos da radiação , Humanos , Técnicas In Vitro , Perfumes/química , Óleos de Plantas/efeitos adversos , Doses de Radiação , Raios Ultravioleta/efeitos adversosRESUMO
Balsam of Peru (PB; Myroxylon pereirae) is a natural product derived from resin of a tropical tree (MyroxyIon balsamum (L.) Harms var. pereirae (Royle) Baillon). Because of its antiseptic and aromatic properties PB or PB-components can be found worldwide not only in many health care and cosmetic products, but also in food items and semiluxury food. PB contains a wide variety of potent contact allergens leading to hypersensitivity reactions not only after topical application but also oral uptake. We report a 51-year-old brewer with chronic eczema of the hands who showed delayed-type patch test reactions against PB and fragrance-mix. Oral PB-challenge led to exacerbation of the eczema 5 and in a repeated test 2 days later. We here review this probably quite often overlooked disease and the therapeutic consequences which require profound knowledge about the wide distribution of PB when advising the patient about a PB-restricted diet. In addition, this unusual case report demonstrates that one has to consider marked delayed hypersensitivity reaction when investigating a systemic contact allergy.