Incidence of Fatal Anaphylaxis: A Systematic Review of Observational Studies.

BACKGROUND: Fatal anaphylaxis is very rare, with an incidence ranging from 0.5 to 1 deaths per million person-years. OBJECTIVE: Based on a systematic review, we aimed to explain differences in the reported incidence of fatal anaphylaxis based on the methodological and demographic factors addressed in the various studies. METHODS: We searched PubMed/MEDLINE, EMBASE, and the Web of Science for relevant retrospective and prospective cohort studies and registry studies that had assessed the anaphylaxis mortality rate for the population of a country or for an administrative region. The research strategy was based on combining the term "anaphylaxis" with "death", "study design", and "main outcomes" (incidence). RESULTS: A total of 46 studies met the study criteria and included 16,541 deaths. The range of the anaphylaxis mortality rate for all causes of anaphylaxis was 0.002-2.51 deaths per million person-years. Fatal anaphylaxis due to food (range 0.002-0.29) was rarer than deaths due to drugs (range 0.004-0.56) or Hymenoptera venom (range 0.02-0.61). The frequency of deaths due to anaphylaxis by drugs increased during the study period (IRR per year, 1.02; 95%CI, 1.00-1.04). We detected considerable heterogeneity in almost all of the meta-analyses carried out. CONCLUSION: The incidence of fatal anaphylaxis is very low and differs according to the various subgroups analyzed. The studies were very heterogeneous. Fatal anaphylaxis due to food seems to be less common than fatal anaphylaxis due to drugs or Hymenoptera venom.

Incidence of Fatal Anaphylaxis A Systematic Review of Observational Studies

Background: Fatal anaphylaxis is very rare, with an incidence ranging from 0.5 to 1 deaths per million person-years. Objective: Based on a systematic review, we aimed to explain differences in the reported incidence of fatal anaphylaxis based on the methodological and demographic factors addressed in the various studies. Methods: We searched PubMed/MEDLINE, EMBASE, and the Web of Science for relevant retrospective and prospective cohort studies and registry studies that had assessed the anaphylaxis mortality rate for the population of a country or for an administrative region. The research strategy was based on combining the term “anaphylaxis” with “death”, “study design”, and “main outcomes” (incidence). Results: A total of 46 studies met the study criteria and included 16,541 deaths. The range of the anaphylaxis mortality rate for all causes of anaphylaxis was 0.002-2.51 deaths per million person-years. Fatal anaphylaxis due to food (range 0.002-0.29) was rarer than deaths due to drugs (range 0.004-0.56) or Hymenoptera venom (range 0.02-0.61). The frequency of deaths due to anaphylaxis by drugs increased during the study period (IRR per year, 1.02; 95%CI, 1.00-1.04). We detected considerable heterogeneity in almost all of the meta-analyses carried out. Conclusion: The incidence of fatal anaphylaxis is very low and differs according to the various subgroups analyzed. The studies were very heterogeneous. Fatal anaphylaxis due to food seems to be less common than fatal anaphylaxis due to drugs or Hymenoptera venom (AU)

Antecedentes: La muerte por anafilaxia es un evento muy excepcional, con una incidencia que varía de 0,5 a 1 muerte por millón de personas/año. Objetivo: Usando las técnicas de una revisión sistemática, nuestro objetivo ha sido explicar las diferencias en la incidencia informada de la muerte por anafilaxia atendiendo a diversos factores metodológicos y demográficos empleados en los diversos estudios de la revisión. Métodos: Se realizaron búsquedas en PubMed/MEDLINE, EMBASE y Web of Science, con el fin de obtener estudios de cohortes y registros prospectivos y retrospectivos relevantes que hubieran evaluado la tasa de muerte por anafilaxia en la población de un país o una región administrativa. La estrategia de investigación se basó en combinar “anafilaxia” con “muerte”, “diseño del estudio” y “resultados principales” (incidencia). Resultados: Un total de 46 estudios cumplieron con los criterios del estudio. Los estudios incluyeron 16.541 muertes. El rango de la tasa de mortalidad por anafilaxia para todas las causas de anafilaxia fue de 0,002 a 2,51 muertes por millón de personas/año. La anafilaxia mortal debida a los alimentos (rango 0,002-0,29) fue más rara que las muertes debidas a medicamentos (rango 0,004-0,56) o veneno de himenópteros (rango 0,02-0,61). La frecuencia de muertes por anafilaxia por fármacos aumentó durante el período de estudio (IRR por año, 1,02; IC del 95%: 1,00-1,04). Se detectó una heterogeneidad considerable en casi todos los metaanálisis realizados. Conclusión: La incidencia de anafilaxia mortal es muy baja y difiere según los distintos subgrupos analizados. Los estudios fueron muy heterogéneos. La muerte por anafilaxia debida a alimentos parece ser menos común que la anafilaxia mortal debida a fármacos o por veneno de himenópteros (AU)

Association Between Severity of Anaphylaxis and Co-occurrence of Respiratory Diseases: A Systematic Review and Meta-analysis of Observational Studies.

BACKGROUND AND OBJECTIVE: Asthma is very prevalent in all grades of severity of anaphylaxis. Asthma and chronic obstructive pulmonary disease (COPD) have been associated with the severity of anaphylaxis. Objective: We carried out a systematic review and meta-analysis to assess the influence of respiratory diseases on the severity of anaphylaxis. METHODS: We searched PubMed/MEDLINE, EMBASE, and the Web of Science for observational studies. The target studies were those that compared the severity of anaphylaxis between patients who had or did not have respiratory diseases. RESULTS: A total of 13 studies assessed the severity of anaphylaxis in respiratory disease. Respiratory disease increased the severity of anaphylaxis (OR, 1.87; 95%CI, 1.30-2.70), as did asthma (OR, 1.89; 95%CI, 1.26-2.83). For the meta-analysis of all studies (adjusted and nonadjusted), COPD increased the severity of anaphylaxis (OR, 2.47; 95%CI, 1.46-4.18). In the case of asthma studies, only 1 study assessed the influence of severity of asthma on severity of anaphylaxis. CONCLUSIONS: Evidence showing that respiratory disease increases the severity of anaphylaxis is low to moderate, although studies do not usually assess the importance of severity of asthma.

Association Between Severity of Anaphylaxis and Co-occurrence of Respiratory Diseases: A Systematic Review and Meta-analysis of Observational Studies

Background: Asthma is very prevalent in all grades of severity of anaphylaxis. Asthma and chronic obstructive pulmonary disease (COPD)have been associated with the severity of anaphylaxis.Objective: We carried out a systematic review and meta-analysis to assess the influence of respiratory diseases on the severity of anaphylaxis.Methods: We searched PubMed/MEDLINE, EMBASE, and the Web of Science for observational studies. The target studies were those thatcompared the severity of anaphylaxis between patients who had or did not have respiratory diseases.Results: A total of 13 studies assessed the severity of anaphylaxis in respiratory disease. Respiratory disease increased the severity ofanaphylaxis (OR, 1.87; 95%CI, 1.30-2.70), as did asthma (OR, 1.89; 95%CI, 1.26-2.83). For the meta-analysis of all studies (adjustedand nonadjusted), COPD increased the severity of anaphylaxis (OR, 2.47; 95%CI, 1.46-4.18). In the case of asthma studies, only 1 studyassessed the influence of severity of asthma on severity of anaphylaxis.Conclusions: Evidence showing that respiratory disease increases the severity of anaphylaxis is low to moderate, although studies do notusually assess the importance of severity of asthma.(AU)

Antecedentes: El asma es muy frecuente en todos los grados de gravedad de la anafilaxia y así mismo el asma y la enfermedad pulmonarobstructiva crónica (EPOC) se han asociado con las anafilaxias graves.Objetivo: Realizamos una revisión sistemática y un meta-análisis para evaluar la influencia de las enfermedades respiratorias en lagravedad de la anafilaxia.Métodos: Se realizaron búsquedas en PubMed / MEDLINE, EMBASE y Web of Science de estudios observacionales, en donde se compararonla gravedad de la anafilaxia entre pacientes que tenían o no enfermedades respiratorias.Resultados: Un total de 13 estudios evaluaron la influencia de las enfermedades respiratorias en la gravedad de la anafilaxia. La enfermedadrespiratoria aumentó la gravedad de la anafilaxia (OR, 1,87; IC 95%, 1,30-2,70). En general, el asma también aumentó la gravedad dela anafilaxia (OR, 1,89; IC del 95%, 1,26-2,83). En el meta-análisis de todos los estudios con EPOC (ajustado y no ajustado), la mismaaumentó la gravedad de la anafilaxia (OR, 2,47; IC del 95%, 1,46-4,18). En los estudios con asma, solo uno evaluó la influencia de lagravedad del asma en la gravedad de la anafilaxia.Conclusiones: La evidencia que muestra que la enfermedad respiratoria aumenta la gravedad de la anafilaxia es baja a moderada, aunquelos estudios no suelen evaluar la importancia de la gravedad del asma.(AU)

Successful treatment of hypocomplementemic urticarial vasculitis with omalizumab: a case report

No disponible

Clinical Profile of Patients With Severe Anaphylaxis Hospitalized in the Spanish Hospital System: 1997-2011.

BACKGROUND AND OBJECTIVE: Studies assessing the severity of anaphylaxis lack a comprehensive approach to collecting data on comorbidities that may worsen prognosis. Objective: Using the Elixhauser score (a systematic index associated with longer stay, hospital charges, and mortality), we determined which comorbidities were associated with more severe anaphylaxis. METHODS: We based our study on the Spanish Ministry of Health database of hospital discharges in Spain between 1997 and 2011. We constructed logistic regression models in which the dependent variables were outcomes related to greater severity (death, cardiac arrest, need for invasive mechanical ventilation or vasopressor drugs, admission to the intensive care unit, and length of stay) and the independent variables were the 30 comorbidities that comprise the Elixhauser score, age, sex, and main causes of anaphylaxis. RESULTS: We found that a higher risk of severe anaphylaxis was associated (3 or more logistic regressions) with age >50 years or having experienced cardiac arrhythmia, coagulation disorder, associated fluid-electrolyte imbalance, chronic pulmonary disease, or Echinococcus anaphylaxis. Likewise, in the adjusted analysis, a higher Elixhauser score was associated with most of the outcomes analyzed for severity of anaphylaxis. CONCLUSIONS: Cardiovascular and respiratory diseases increase the severity of anaphylaxis, and the resulting poor health status (represented as a higher Elixhauser score) is associated with more severe anaphylaxis.

Clinical profile of patients with severe anaphylaxis hospitalized in the Spanish Hospital System: 1997-2011

Background: Studies assessing the severity of anaphylaxis lack a comprehensive approach to collecting data on comorbidities that may worsen prognosis. Objective: Using the Elixhauser score (a systematic index associated with longer stay, hospital charges, and mortality), we determined which comorbidities were associated with more severe anaphylaxis. Methods: We based our study on the Spanish Ministry of Health database of hospital discharges in Spain between 1997 and 2011. We constructed logistic regression models in which the dependent variables were outcomes related to greater severity (death, cardiac arrest, need for invasive mechanical ventilation or vasopressor drugs, admission to the intensive care unit, and length of stay) and the independent variables were the 30 comorbidities that comprise the Elixhauser score, age, sex, and main causes of anaphylaxis. Results: We found that a higher risk of severe anaphylaxis was associated (3 or more logistic regressions) with age >50 years or having experienced cardiac arrhythmia, coagulation disorder, associated fluid-electrolyte imbalance, chronic pulmonary disease, or Echinococcus anaphylaxis. Likewise, in the adjusted analysis, a higher Elixhauser score was associated with most of the outcomes analyzed for severity of anaphylaxis. Conclusions: Cardiovascular and respiratory diseases increase the severity of anaphylaxis, and the resulting poor health status (represented as a higher Elixhauser score) is associated with more severe anaphylaxis (AU)

Antecedentes: Los estudios que recogen datos sobre comorbilidades que empeoran la gravedad de la anafilaxia, carecen de un acercamiento exhaustivo. Objetivo: Usando la puntuación de Elixhauser (un sistema de puntuación asociado con mayor estancia hospitalaria, mayor gasto hospitalario y muerte), establecimos que comorbilidades fueron asociadas con anafilaxia grave. Métodos: Usamos para el estudio la base de datos de altas hospitalarias del Ministerio Español de Sanidad, entre 1997 a 2011. Se obtuvo varios modelos de regresión logística, en las cuales las variables dependientes fueron desenlaces relacionados con eventos asociados habitualmente a una gran gravedad de los episodios (muerte, parada cardio-respiratoria, necesidad de uso de ventilación mecánica invasiva o medicamentos vaso-presores, ingreso en la Unidad de Cuidados Intensivos y duración de la estancia) y las variables independientes fueron las 30 comorbilidades que comprenden la puntuación Elixhauser, junto con edad, sexo y las grandes causas de anafilaxia. Resultados: Encontramos que un mayor riesgo para anafilaxia grave estuvo asociado (3 o más regresiones logísticas con significación estadística) con una edad de más de 50 años, o haber experimentado arritmias cardiacas, alteraciones de la coagulación, disbalance hidro-electrolítico, enfermedad pulmonar crónica o anafilaxia por Echinococcus. Así mismo, en un análisis ajustado, una puntuación mayor del sistema Elixhauser se asoció con la mayoría de las variables de desenlace usadas para analizar la gravedad de la anafilaxia. Conclusiones: Enfermedades cardio-vasculares y respiratorias incrementan la gravedad de la anafilaxia y un mal estado de salud (representado por mayores puntuaciones del Sistema de puntuación de Elixhauser) se asocian con mayor gravedad de la anafilaxia (AU)

Clinical Practice Guidelines for Diagnosis and Management of Hypersensitivity Reactions to Contrast Media.

The objective of these guidelines is to ensure efficient and effective clinical practice. The panel of experts who produced this consensus document developed a research protocol based on a review of the literature. The prevalence of allergic reactions to iodinated contrast media (ICM) is estimated to be 1:170 000, that is, 0.05%-0.1% of patients undergoing radiologic studies with ICM (more than 75 million examinations per year worldwide). Hypersensitivity reactions can appear within the first hour after administration (immediate reactions) or from more than 1 hour to several days after administration (nonimmediate or delayed reactions). The risk factors for immediate reactions include poorly controlled bronchial asthma, concomitant medication (eg, angiotensin-converting enzyme inhibitors, ß-blockers, and proton-pump inhibitors), rapid administration of the ICM, mastocytosis, autoimmune diseases, and viral infections. The most common symptoms of immediate reactions are erythema and urticaria with or without angioedema, which appear in more than 70% of patients. Maculopapular rash is the most common skin feature of nonimmediate reactions (30%-90%). Skin and in vitro tests should be performed for diagnosis of both immediate and nonimmediate reactions. The ICM to be administered will therefore be chosen depending on the results of these tests, the ICM that induced the reaction (when known), the severity of the reaction, the availability of alternative ICM, and the information available on potential ICM cross-reactivity. Another type of contrast media, gadolinium derivatives, is used used for magnetic resonance imaging. Although rare, IgE-mediated reactions to gadolinium derivatives have been reported.

Clinical practice guidelines for diagnosis and management of hypersensitivity reactions to contrast media

The objective of these guidelines is to ensure efficient and effective clinical practice. The panel of experts who produced this consensus document developed a research protocol based on a review of the literature. The prevalence of allergic reactions to iodinated contrast media (ICM) is estimated to be 1:170 000, that is, 0.05%-0.1% of patients undergoing radiologic studies with ICM (more than 75 million examinations per year worldwide). Hypersensitivity reactions can appear within the first hour after administration (immediate reactions) or from more than 1 hour to several days after administration (nonimmediate or delayed reactions). The risk factors for immediate reactions include poorly controlled bronchial asthma, concomitant medication (eg, angiotensin-converting enzyme inhibitors, ß-blockers, and proton-pump inhibitors), rapid administration of the ICM, mastocytosis, autoimmune diseases, and viral infections. The most common symptoms of immediate reactions are erythema and urticaria with or without angioedema, which appear in more than 70% of patients. Maculopapular rash is the most common skin feature of nonimmediate reactions (30%-90%). Skin and in vitro tests should be performed for diagnosis of both immediate and nonimmediate reactions. The ICM to be administered will therefore be chosen depending on the results of these tests, the ICM that induced the reaction (when known), the severity of the reaction, the availability of alternative ICM, and the information available on potential ICM cross-reactivity. Another type of contrast media, gadolinium derivatives, is used used for magnetic resonance imaging. Although rare, IgE-mediated reactions to gadolinium derivatives have been reported (AU)

El contenido y las pautas recomendadas en este documento están dirigidas a lograr una práctica clínica más eficiente y eficaz. El panel de expertos que participó en esta guía de consenso desarrolló un protocolo para revisar lo publicado sobre el tema. La prevalencia de las reacciones alérgicas a medios de contraste iodados (MCI) se estima en 1:170.000, lo que representa un 0,05% -0,1% de los pacientes sometidos a estudios radiológicos con MCI (más de 75 millones de administraciones por año en todo el mundo). Las reacciones alérgicas por hipersensibilidad pueden aparecer dentro de la primera hora tras la administración (reacciones inmediatas) o en un rango de tiempo desde una hora hasta varios días después de la administración (reacciones no inmediatas o tardías). Existen factores de riesgo para las reacciones inmediatas tales como: mal control previo del asma bronquial, uso concomitante de inhibidores de la ECA, beta bloqueantes o inhibidores de la bomba de protones, administración rápida del fármaco, antecedente de mastocitosis, coexistencia de enfermedades autoinmunes o de infecciones virales. Los síntomas más comunes de las reacciones inmediatas son eritema y urticaria con o sin angioedema, apareciendo en más de un 70% de los pacientes que sufrieron reacciones. Las reacciones no inmediatas más comunes son las erupciones maculopapulares (30-90%). Para el diagnóstico de reacciones tanto inmediatas como no inmediatas se deben realizar pruebas cutáneas y pruebas in vitro. Para elegir el MCI que posteriormente puede ser administrado se tendrán en cuenta los resultados de las pruebas cutáneas e in vitro realizadas, el MCI que indujo la reacción (si se conoce), la gravedad de la misma, la disponibilidad de otros MCIs alternativos y la información disponible sobre la potencial reactividad cruzada entre los distintos MCIs. Otro tipo de medios de contraste, son los utilizados en la resonancia magnética (RMN), que son derivados de gadolinio. Aunque infrecuentes, se han descrito reacciones mediadas por IgE a estos medios de contraste (AU)

Self-Management of Anaphylaxis Is Not Optimal.

BACKGROUND: Our objective was to ascertain the degree of adherence to recommendations made to patients with anaphylaxis, most of whom were attended in our allergy outpatient clinic. METHODS: A questionnaire was sent to 1512 patients who had experienced anaphylaxis and completed by 887. The chosen definition of anaphylaxis was that of the National Institute of Allergy and Infectious Diseases and the Food Allergy and Anaphylaxis Network Symposium. We evaluated the prescription, purchase, and use of epinephrine auto-injectors and oral drugs, as well as the avoidance of allergens involved in previous anaphylaxis episodes. RESULTS: Most patients (94.53%) reported that they had received advice on avoidance of responsible allergens after their allergy workup. Epinephrine auto-injectors and oral drugs were prescribed according to the subtype of anaphylaxis. Only 30.74% of patients used the epinephrine auto-injector; 54.26% took oral medication. Most patients (88.3%) avoided the allergen. CONCLUSIONS: Despite general agreement that anaphylaxis occurring in the community should be treated with epinephrine auto-injectors, use of these devices to treat recurrences was low in our patients. Oral medication intake was more common than the epinephrine auto-injector in all subtypes. In order to increase adherence to epinephrine auto-injectors, it is necessary to think beyond the measures recommended during regular visits to allergy outpatient clinics.

Self-management of anaphylaxis is not optimal

Background: Our objective was to ascertain the degree of adherence to recommendations made to patients with anaphylaxis, most of whom were attended in our allergy outpatient clinic. Methods: A questionnaire was sent to 1512 patients who had experienced anaphylaxis and completed by 887. The chosen definition of anaphylaxis was that of the National Institute of Allergy and Infectious Diseases and the Food Allergy and Anaphylaxis Network Symposium. We evaluated the prescription, purchase, and use of epinephrine auto-injectors and oral drugs, as well as the avoidance of allergens involved in previous anaphylaxis episodes. Results: Most patients (94.53%) reported that they had received advice on avoidance of responsible allergens after their allergy workup. Epinephrine auto-injectors and oral drugs were prescribed according to the subtype of anaphylaxis. Only 30.74% of patients used the epinephrine auto-injector; 54.26% took oral medication. Most patients (88.3%) avoided the allergen. Conclusions: Despite general agreement that anaphylaxis occurring in the community should be treated with epinephrine auto-injectors, use of these devices to treat recurrences was low in our patients. Oral medication intake was more common than the epinephrine auto-injector in all subtypes. In order to increase adherence to epinephrine auto-injectors, it is necessary to think beyond the measures recommended during regular visits to allergy outpatient clinics (AU)

Antecedentes: Guías clínicas y documentos de posicionamiento recomiendan planes de acción urgentes personalizados para los pacientes que han tenido anafilaxia. El cumplimiento de estos planes es generalmente bajo. Objetivo: Nuestro objetivo fue determinar el grado de adherencia a diferentes recomendaciones hechas a los pacientes con anafilaxia, que en la mayoría de los cuales fueron atendidos en la consulta externa de Alergia de nuestro hospital. Métodos: Se envió un cuestionario a 1.512 pacientes que habían sufrido un episodio previo de anafilaxia y este fue completado por 887. La definición elegida de anafilaxia fue la del Instituto Nacional de Alergias y Enfermedades Infecciosas y el Simposio de la Food Allergy and Anaphylaxis Network (NIAID-FAAN). Se evaluó la prescripción, la compra y el uso de auto-inyectores de adrenalina y medicamentos orales, así como la evitación de alérgenos implicados en los episodios de anafilaxia anteriores. Resultados: La mayoría de los pacientes (94,53%) informaron que habían sido aconsejados sobre la evitación de alérgenos responsables después de su evaluación alergológica. Los auto-inyectores de adrenalina y los medicamentos orales se prescribieron de forma diferente según el subtipo de anafilaxia. Sólo el 30.74% de los pacientes utilizaron el auto inyector de adrenalina y el 54,26% tomo la medicación oral. La mayoría de los pacientes (88,3%) evitaron el alérgeno. Conclusiones: A pesar del acuerdo general que los episodios de anafilaxia que ocurren en la comunidad deben ser tratados con autoinyectores de adrenalina, el uso de estos dispositivos para el tratamiento de las recurrencias fue baja en nuestros pacientes. La ingesta oral de medicamentos es más común que el auto inyector de adrenalina en todos los subtipos. Con el fin de aumentar la adherencia a autoinyectores de adrenalina, es necesario investigar más allá de las medidas recomendadas durante las visitas regulares a las consultas de Alergia (AU)

Recurrence of Anaphylaxis in a Spanish Series

Background: Anaphylaxis is a potentially fatal condition, and many patients experience recurrence. Objective: We report the incidence of first recurrence of anaphylaxis in our series and examine the risk factors associated with recurrence. Methods: A validated questionnaire was sent to 1512 patients and completed by 887. The chosen definition of anaphylaxis was that of the National Institute of Allergy and Infectious Diseases/Food Allergy and Anaphylaxis Network Symposium. We evaluated the incidence of first recurrence of anaphylaxis overall and by subtype (eg, drugs and foods) and attempted to determine associated risk factors. Results: The total incidence rate of the first recurrence of anaphylaxis (same subtype) was 3.2 episodes per 100 person-years (95%CI, 2.83-3.63). Incidence was lower in drug anaphylaxis (2.0 episodes per 100 person-years) than in latex and food anaphylaxis (8.6 and 5.6 episodes per 100 person-years, respectively). Cox and ordinal logistic regression models revealed that a first recurrence was less likely with drug anaphylaxis than with food anaphylaxis. The risk of experiencing 1 or more recurrences was higher for foods, exercise, and idiopathic causes than for the other subtypes. Conclusions: The incidence rate for a first recurrence of the same subtype of anaphylaxis was 2 to 6 times lower than that published by other authors. Recurrence of anaphylaxis is more common in subtypes with an increased prevalence of atopy (food, idiopathic, latex) than in other subtypes (drugs, Anisakis). Consequently, particular attention should be paid to prevention and care in this population (AU)

Antecedentes: Aunque la anafilaxia es una enfermedad potencialmente fatal, muchos pacientes sufren recurrencias de la misma. Objetivo: Nuestro objetivo fue conocer la incidencia de la primera recurrencia de la anafilaxia en nuestra serie y examinar los factores de riesgo asociados a la misma. Métodos: Un cuestionario validado fue enviado a 1512 pacientes y completado por 887. La definición de anafilaxia elegida fue la del Simposio NIAID-FAAN (National Institute of Allergy and Infectious Diseases/Food Allergy and Anaphylaxis Network). Se evaluó la incidencia de la primera recurrencia de la anafilaxia en general y por subtipo (por ejemplo, medicamentos y alimentos) y se trató de determinar factores de riesgo asociados a la recurrencia. Resultados: La tasa de incidencia total de la primera recurrencia de la anafilaxia (el mismo subtipo) fue de 3,2 episodios por 100 personas año (95% CI, 2,83 a 3,63). La incidencia fue menor en la anafilaxia por medicamentos (2,0 episodios por 100 personas-año) que en la anafilaxia por látex y alimentos (8,6 y 5,6 episodios por 100 personas-año respectivamente). Los modelos de regresión de Cox y logística ordinal revelaron que la primera recurrencia fue menos probable con anafilaxia por medicamentos que con la anafilaxia alimentaria. El riesgo de sufrir una o más recurrencias fue mayor para los alimentos, el ejercicio, y anafilaxia idiopática que para los otros subtipos. Conclusiones: La tasa de incidencia de una primera recurrencia del mismo subtipo de anafilaxia fue 2-6 veces inferior a la publicada por otros autores. La recurrencia de la anafilaxia es más común en los subtipos con una mayor prevalencia de atopia (alimentos, idiopática, látex) que en los otros subtipos (medicamentos, Anisakis). Por lo tanto, se debería prestar especial atención a la prevención y atención de estas poblaciones (AU)

Incidence of anaphylaxis in the city of Alcorcon (Spain): a population-based study.

BACKGROUND: Relatively few studies have examined the incidence of anaphylaxis in the general population. OBJECTIVE: To report the incidence of anaphylaxis among the general population of the city of Alcorcon, Spain, using various public health care databases. METHODS: Episodes of anaphylaxis were recovered using validated alphanumeric strings in different fields of electronic clinical records used in the different public health settings in the city of Alcorcon (primary care, Emergency Department, hospitalized patients and Allergy Outpatient Clinic). Patients with anaphylaxis were tracked across the different clinical settings in Alcorcon. RESULTS: The incidence of anaphylaxis in Alcorcon was 103.37 episodes per 100 000 person-years (total standardized incidence rate of 112.2). There was a peak of 313.58 episodes in the 0-4 years age group and a different distribution of incidence rates (although non-significant) among different age groups between male patients and female patients. In most age groups, incidence tended to be higher for female patients aged over 10 years. Patients were attended at two or more levels in 76.78% of episodes, and a new evaluation was often made at a primary care centre (71.43%), Allergy Outpatient Clinic (75.6%), or both after the episode (58.93%). CONCLUSION AND CLINICAL RELEVANCE: This study revealed a higher rate of anaphylaxis than that in previous studies, although this incidence rate is probably lower than the real incidence rate. Studies exploring potential methodological, genetic and environmental factors accounting for these higher rates of anaphylaxis are required.

Incidence of anaphylaxis and subtypes of anaphylaxis in a general hospital emergency department.

BACKGROUND: The absence of large-scale international studies means that data on anaphylaxis in emergency departments in different geographic areas are still necessary. OBJECTIVE: To determine the incidence of anaphylaxis and subtypes of anaphylaxis and their distribution by age group in the emergency department of Hospital Universitario Fundación Alcorcon, Alcorcon (Madrid), Spain. METHODS: Our study was performed between 2004 and 2005. We used the definition of anaphylaxis established by the NIAID-FAAN Symposium. Patient information was collected from the electronic clinical records of the emergency department using alphanumeric strings to identify acute allergic illnesses. This strategy recovered 91.7% of all anaphylaxis episodes in a pilot study. RESULTS: We observed a crude cumulative incidence of 0.9 episodes of anaphylaxis per 1000 emergency episodes (95% confidence interval [CI], 0.8-1.1), and 0.8 episodes per 1000 people (95% CI, 0.7-0.9). Standardized cumulative incidence of anaphylaxis according to the Standardized European Population was 1.1 (95% CI, 0.9-1.2). On analyzing the 213 cases of anaphylaxis, we discovered that the main cause was food (28.6%), followed by drugs (28.2%), unknown causes (27.2%), Anisakis (10.8%), Hymenoptera venom (3.3%), exercise (2.4%), and latex (0.9%). Food-induced anaphylaxis was less frequent in all groups older than the 0-4 age group in both reference populations (people who attend the emergency department and the general population). CONCLUSIONS: The cumulative incidence of anaphylaxis in our emergency department is low. Anaphylaxis by foods is more frequent in the 0-4 year group than in the other age groups. Drugs and food are the most frequent causes of anaphylaxis in our emergency department.

Thrombocytopenia and anaphylaxis secondary to heparin in a hemodialysis patient.

AIMS: We describe a rare case of anaphylaxis and thrombocytopenia whose cause was heparin used during hemodialysis sessions. CASE REPORT: A 77-year-old woman suffered five consecutive episodes of vomiting, tachypnea, wheezing or rales, immediately after initiating hemodialysis. In the first of these episodes, arterial pressure was undetectable. In all of the episodes there was evidence of the presence of hypoxia (always below 60 mmHg) and thrombocytopenia (always below l00,000/microl,, with partial platelets recovery among episodes. The episodes started immediately after hemodialysis sessions and heparin infusion; either sodium heparin or enoxaparin was used. Utilization of different filters was not able to stop the episodes. These were stopped when a switch from heparin to hirudin was tested. Tryptase levels, as a marker of mast cells activation and anaphylaxis, were not increased in two of the episodes which were assessed. IgG antibodies against heparin-PF4 complex was detected at high levels. DISCUSSION: A diagnosis of concomitant anaphylaxis and thrombocytopenia caused by sodium heparin and a low-molecular weight heparin (enoxaparin) were assumed.