Specific questionnaire detects a high incidence of intra-operative hypersensitivity reactions

OBJECTIVE: To assess the incidence of intra-operative immediate hypersensitivity reactions and anaphylaxis. METHODS: A cross-sectional observational study was conducted at the Department of Anesthesiology, University of São Paulo School of Medicine, Hospital das Clínicas, São Paulo, Brazil, from January to December 2010. We developed a specific questionnaire to be completed by anesthesiologists. This tool included questions about hypersensitivity reactions during anesthesia and provided treatments. We included patients with clinical signs compatible with immediate hypersensitivity reactions. Hhypersensitivity reactions were categorized according to severity (grades I-V). American Society of Anesthesiologists physical status classification (ASA 1-6) was analyzed and associated with the severity of hypersensitivity reactions. RESULTS: In 2010, 21,464 surgeries were performed under general anesthesia. Anesthesiologists answered questionnaires on 5,414 procedures (25.2%). Sixty cases of intra-operative hypersensitivity reactions were reported. The majority patients (45, 75%) had hypersensitivity reactions grade I reactions (incidence of 27.9:10,000). Fifteen patients (25%) had grade II, III or IV reactions (intra-operative anaphylaxis) (incidence of 7:10,000). No patients had grade V reactions. Thirty patients (50%) were classified as ASA 1. The frequency of cardiovascular shock was higher in patients classified as ASA 3 than in patients classified as ASA 1 or ASA 2. Epinephrine was administered in 20% of patients with grade III hypersensitivity reactions and in 50% of patients with grade II hypersensitivity reactions. CONCLUSIONS: The majority of patients had hypersensitivity reactions grade I reactions; however, the incidence of intra-operative anaphylaxis was higher than that previously reported in the literature. Patients with ASA 3 had more severe anaphylaxis; however, the use of epinephrine was not prescribed in all of these cases. Allergists and anesthesiologists should implement preventive measures to reduce the occurrence of anaphylaxis.

IgE, IgG4 e IgA específicas na alergia ao látex / Specific IgE, IgG4, and IgA in latex allergy

Objetivo: A alergia ao látex é considerada um problema mundial de saúde por estar associada a reações potencialmente fatais. O objetivo principal deste estudo é identificar fatores clínico-laboratoriais associados à sensibilização e alergia ao látex, avaliando as concentrações de IgE, IgG4 e IgA específicas nestas condições. Métodos: Estudo observacional transversal em uma coorte de 400 crianças e adolescentes com defeito do fechamento do tubo neural. Os pacientes realizaram entrevista clínica e foram submetidos a coleta de sangue periférico para a detecção dos níveis séricos de IgE, IgG4 e IgA específicas para látex. As prevalências de sensibilização e alergia ao látex foram calculadas e as variáveis clínico-laboratoriais coletadas foram analisadas. Resultados: A prevalência de sensibilização e de alergia ao látex em pacientes com defeito de fechamento do tubo neural foi de 33,2% e 12,2%, respectivamente. As manifestações clínicas de alergia ao látex mais frequentes foram as cutâneas (79,6%), mas anafilaxia foi observada em 4,75% dos pacientes. Os fatores clínico-cirúrgicos associados à alergia ao látex foram identificados e um escore de sintomas para rastrear os pacientes foi desenvolvido. A concentração de IgE sérica específica para látex ≥ 0,77 kUA/L tem boa acurácia para diferenciar os pacientes sensibilizados assintomáticos dos alérgicos. As dosagens de IgE sérica específica para alérgenos recombinantes também apresentaram boa acurácia no diagnóstico da alergia. Conclusões: Maior concentração de IgE específica para látex e Hevb5, menor concentração de IgG4 específica para látex e escore de sintomas ≥ 40% estiveram associados com alergia ao látex.

Objective: Latex allergy is considered a global health problem because it is associated with life-threatening reactions. The main objective of this study was to identify clinical and laboratory factors associated with sensitization and allergy to latex, assessing the concentrations of latex-specific IgE, IgG4, and IgA. Methods: This was an observational study of a cohort of 400 children and adolescents with neural tube closure defect. Patients underwent a clinical interview and had their blood drawn for the measurement of serum levels of latex-specific IgE, IgG4, and IgA. The prevalence rates of sensitization and allergy to latex were calculated, and clinical and laboratory variables were analyzed. Results: The prevalence rates of sensitization and allergy to latex in patients with neural tube closure defects were 33.2 and 12.2%, respectively. Cutaneous manifestations of latex allergy were the most common ones (79.6%), but anaphylaxis was observed in 4.75% of the patients. Clinical and surgical factors associated with latex allergy were identified, and a symptom scoring system was developed as a screening tool. A latex-specific IgE concentration ≥ 0.77 kUA/L showed good accuracy to differentiate between asymptomatic sensitization and allergy. The measurement of specific IgE to recombinant allergens also showed good accuracy in the diagnosis of allergy. Conclusions: Higher concentrations of latex-specific IgE and Hevb5, lower concentrations of latex-specific IgG4, and a symptom score ≥ 40% were associated with latex allergy.

Testes de provocação com drogas: positividade e segurança / Drug Provocation Tests: positivity and safety

O teste de provocação com droga (TPD) é o padrão-ouro para diagnóstico das reações adversas a drogas (RAD). Analisamos resultados de TPD e discutimos os riscos de reações sistêmicas.Método: Estudo retrospectivo e descritivo no qual foram avaliados os prontuários de 500 pacientes com história de RAD no período de janeiro de 2005 a abril de 2009 e selecionados aqueles submetidos a TPD simples cego placebo controlado. Foram realizados TPD com antibióticos (ATB), anti-inflamatórios não esteroidais (AINE), anestésicos locais (A L) e outros. Caracterizamos esta população quanto ao sexo, idade, testes positivos e ocorrência de reações graves. Resultados: Foram realizados 243 TPD em 198 pacientes, 80,8% mulheres e a média de idade de 39,9 anos. Dentre os TPD, realizamos 19 testes com ATB, 26 com AINE seletivos da COX2, 7 com dipirona, 4 com ácido acetil salicílico, 44 com paracetamol, 93 com AL e 17 com outras medicações. Ocorreram 10 TPD positivos (4,1%) e 4 (1,6%) duvidosos. Os testes positivos ocorreram com ATB (2/19), AINE seletivos da COX 2 (2/26), paracetamol (3/44), AL (3/93). Ocorreram 2 reações graves, sendo 1 choque anafilático por cefalexina e 1 anafilaxia sem choque por bupivacaína. Em 4 pacientes (1,6%) houve positividade para o placebo antes da administração da droga ativa.Conclusões: Testes de provocação com drogas são seguros para realização na prática clínica. Os testes devem ser controlados com placebo e supervisionados por um alergista experiente em provocações com drogas.

Drug provocation test (DPT) is considered the gold standard to establish the diagnosis of adverse drug reactions (ADR). We analyzed DPTs results and we discuss severe systemic reactions to them.Methods: A retrospective analysis was conducted on medicai record of 500 patients with ADR history between January of 2005 and April of 2009. Provocation tests, which were single-blind placebo controlled, are reported. There were DPTs with antibiotics, local anesthetics, non¬steroldal antiinflammatory drugs, among other drugs. Patient's features, DPT positivity and its severe adverse reactions were analyzed. Results: The study sample included 243 DPTs in 198 patients (80.8% women) and the mean age was 39.9 years. Ninety-three DPTs were done with local anesthetics, 19 with antibiotics, 44 with acetaminophen, 26 with COX 2 inhibitors, 7 with dipyrone, 4 with aspirin and 17 with other drugs. There were 10 (4.1%) positive and 4 (1,6%) inconclusive tests. The positive tests were due to antibiotics (2/19), COX 2 inhibitors (2/26), acetaminophen (3/44) and local anesthetics (3/93). Two reactions were severe: one anaphylactic shock due to cephalexin and one anaphylaxis without shock due to bupivacaine. Four patients (1,6%) had placebo reaction, before drug administration.Conclusions: Drug provocation tests are safe to be performed in clinicai practice. They should be placebo controlled and done under allergist supervisiono.

Uso a longo prazo de alternativas terapêuticas aos anti-inflamatórios não-esteroidais / Long term use of therapeutic alternatives for non-steroidal anti-inflammatory drugs

A benzidamina e o etoricoxibe são drogas que podem ser utilizadas como alternativa terapêutica em pacientes com hipersensibilidade aos anti-inflamatórios não-esteroidais (AINEs). O objetivo do estudo foi avaliar a utilização destas medicações a longo prazo em pacientes com teste de provocação negativo. Métodos: Pacientes com hipersensibilidade aos AINEs que apresentaram teste de provocação negativo foram contactados por telefone e questionados sobre a utilização posterior da drogatestada. Os pacientes que responderam que não voltaram a utilizar a droga foram questionados sobre os motivos pelo qualnão usaram. Resultados: Dos 53 pacientes testados, 50 apresentaram teste de provocação negativo. Destes, 36 foram contactados por telefone e 18 haviam utilizado novamente a droga sem qualquer reação. Dentre os que não foram expostos novamente aos medicamentos, metade não o fez porque não julgou necessário, e a outra metade por receio de uma nova reação. Conclusões: O teste de provocação oral é seguro para a determinação de alternativas terapêuticas, mas a eficácia do mesmo está diretamente relacionada ao entendimento do paciente quanto a possibilidade de novas reações. Além disso, as indicações para o teste também devem ser revistas.

Benzydamine and etoricoxib are drugs that can be used as an alternative therapy in patients with hypersensitivity to thenon-steroidal anti-inflammatory drugs (NSAIDs). The aim of the study was to evaluate the long-term use of these drugs inpatients with a negative drug provocation test. Methods: Patients with NSAIDs hypersensitivity that presented a negative drug provocation test were contacted by telephone and questioned about the subsequent use of the tested drug. The patients who answered that they had not used the drug again were questioned on the reasons for not using it. Results: Of the 53 patients tested, 50 presented a negative drug provocation test. Of these, 36 were contacted by telephone and 18 had used the drug again without any reaction. Among the ones that were not exposed again to the drugs, halfof them had not used because they didn't judge necessary, andt he other half were afraid of a new reaction. Conclusions: The drug provocation test is safe for the determination of an alternative therapy, but the effectiveness oft he test is directly related to the patient's understanding about the possibility of new reactions. Besides, the indications for the test should also be reviewed.

Reações de hipersensibilidade à insulina / Insulin hypersensitivity reactions

As reações de hipersensibilidade à insulina têm diminuído significativamente após a introdução da preparação de insulina humana. No entanto, alguns casos continuam sendo observados na prática clínica. Revisamos os principais aspectos relacionados à fisiopatologia, às manifestações clínicas, ao diagnóstico e ao tratamento das reações de hipersensibilidade a insulina. As reações à insulina podem estar relacionadas a qualquerum dos quatro mecanismos de Gell e Coombs. As manifestações clínicas surgem geralmente nas quatro primeiras semanas de tratamento e incluem mais frequentemente reações locais, mas também urticária, angioedema e anafilaxia. A sensibilização à insulina pode ser avaliada pelo teste cutâneo de leitura imediata, pesquisa de IgE sérica específica, teste intradérmico e pesquisa de IgG específica. O tratamento envolve o uso deadrenalina, anti-histamínicos e corticosteróides, dependendo do tipo e gravidade da reação. Em alguns casos a dessensibilização deve ser considerada.

Hypersensitivity reactions to the insulin have been decreesing significantly after the introduction of the preparation of human insulin. However, some cases continue being observed in clinical practice. We revised the main aspects related to the physiopathology, clinical manifestations, diagnosis and treatmentof the insulin hypersensitivity reactions. Insulin reactions can be related with any one of the four mechanisms of Gell and Coombs. Clinical manifestations usually appear in the first 4 weeks of treatment and they more frequently include local reactions, but also urticaria, angioedema and anaphylaxis. Insulin sensitization can be evaluated by the prick test, serum specific IgE, intradermal test and serum specific IgG.