Molecular analysis of phenotypic interactions of asthma.

INTRODUCTION: Asthma is a heterogeneous disease characterized by multiples respiratory symptoms; this is a polygenic entity that involves a complex interaction of environmental factors and inherent to the individual. To understand the development of asthma, some phenotypes have been proposed. OBJECTIVE: This work's purpose was to explore different molecules related to asthma development and to define each phenotype's specific characteristics. MATERIAL AND METHODS: 96 adult patients diagnosed with asthma before any treatment were enrolled in the protocol. Spirometric parameters, circulating leukocytes, serum IgE, body mass index, exhaled nitric oxide (FENO), and leukotrienes (LTB4) in urine were determined in each patient. The presence of asthma phenotypes proposed by the Global Initiative for Asthma (GINA) were explored: A) Allergic asthma, B) Non-allergic asthma, C) Late-onset asthma, D) Asthma with persistent airflow limitation, and E) Asthma with overweight and obesity. RESULTS: In the cohort analyzed, we found four of phenotypes proposed by GINA; however, these phenotypes overlapped, due to this, 4 groups were integrated with allergic, non-allergic and obese patients, which were the main phenotypes. The main overlap was that of patients not-obese allergic, and was characterized by earlier onset, elevated levels of IgE, LTB4 and inflammasome related cytokines. Non-allergic patients had a significant association between interleukin (IL)-18 and IL-18 binding protein (BP) with narrow ratio between these cytokines. Finally, LTB4 had remarkable capacity to discriminate between allergic and not allergic patients. CONCLUSIONS: Asthmatic phenotypes exist as interrelated characteristics and not as discrete entities. High levels of leukotrienes and IgE are hallmarks in the allergic phenotype of asthma.

[Hypersensitivity reactions to food additives]. / Reacciones de hipersensibilidad a aditivos alimentarios.

Food additives are ingredients that are intentionally added to food in order to modify its physical, chemical, biological, or sensorial characteristics. Food additives may act as allergens and generate IgE-mediated immune reactions, or they may act as pseudo allergens and generate non-IgE-mediated immune reactions. Such reactions can generate diverse clinical pictures or they may exacerbate diseases as diverse as eosinophilic esophagitis, bronchial asthma, atopic dermatitis, contact dermatitis, chronic urticaria, or anaphylaxis. Thousands of food additives are being used daily in industrialized countries and, although their use has been globalized, there is not much science information about their adverse effects; especially about their hypersensitivity reactions that, despite being reported in literature as rare, it is probably because they are under-diagnosed due to the fact that they require a high level of clinical suspicion by the physician, and the proof of a causal connection between the symptomatology and the food additive. Hypersensitivity reactions to food additives must be suspected in patients who report symptoms with the intake of multiple commercially prepared foods or to a commercially prepared food without presenting symptoms with the intake of the natural or homemade version of the same food or with the presence of idiopathic reactions. The diagnostic role of the in vivo or in vitro test against IgE (Skin Tests or RAST) is limited to some natural food additives. The gold standard diagnosis that shows causality between the additive and the symptoms is the oral food challenge. The treatment shall always be the elimination of the food additive from the patient's diet.

Los aditivos alimentarios son ingredientes agregados intencionalmente para modificar las características físicas, químicas, biológicas o sensoriales de los alimentos; pueden actuar como alérgenos y generar reacciones inmunológicas mediadas por IgE o como pseudoalérgenos y generar reacciones inmunológicas no mediadas por IgE. Dichas reacciones pueden provocar diversos cuadros clínicos o exacerbar diferentes enfermedades: esofagitis eosinofílica, asma bronquial, dermatitis atópica, dermatitis de contacto, urticaria crónica o anafilaxia. Diariamente, miles de aditivos alimentarios son utilizados en países industrializados y aunque su uso se ha globalizado, se dispone de poca información científica sobre sus efectos adversos, particularmente sobre las reacciones de hipersensibilidad, las cuales son raras en la literatura, muy probablemente porque son infradiagnosticadas debido a que requieren un alto grado de sospecha clínica por parte del médico y la demostración de una relación de causalidad entre la sintomatología y el aditivo alimentario. Las reacciones de hipersensibilidad a aditivos alimentarios deben ser sospechadas en paciente con reporten síntomas a múltiples alimentos o a un alimento de preparación comercial sin sintomatología ante la ingesta natural o casera del mismo o ante reacciones idiopáticas. El papel diagnóstico de la prueba in vivo o in vitro contra IgE (pruebas cutáneas o RAST) está limitado a algunos aditivos alimentarios naturales. La prueba diagnóstica que demuestra causalidad entre el aditivo y la sintomatología es el reto oral alimentario. El tratamiento deberá ser siempre la eliminación del aditivo de la dieta.

Tolerance Induction to Antituberculosis Drugs in a Patient With Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis Overlap.

Tolerance induction and desensitization in Stevens-Johnson syndrome (SJS) or in toxic epidermal necrolysis (TEN) have been described as an absolute contraindication by some authors, but there are cases where there is no treatment alternative. Tuberculosis (TB) remains a leading cause of morbidity and mortality in developing countries and ranks alongside HIV as a leading cause of death worldwide. Severe drug reactions, such as SJS and TEN, occurring in these individuals are lifethreatening. Since alternative therapies for TB are limited, the role of desensitization and reintroduction becomes essential. We describe a case of tolerance induction to anti-TB drugs in a patient with SJS/TEN overlap syndrome using a specifically designed premedication, comedication, and desensitization protocol.

[Perioperative allergy. A 3-year experience]. / Alergia perioperatoria. Experiencia de tres años.

BACKGROUND: Perioperative hypersensitivity reactions constitute a global health problem, with an estimated incidence of 1 per 100,000 procedures and a mortality rate of 0.1 to 9 %. Main risk factors are a history of allergy to other drugs, atopy, associated psychiatric disorders and previous surgeries. OBJECTIVES: To determine the frequency of sensitization and the type of drugs involved in perioperative allergy in a tertiary care hospital, over a 3-year period. METHODS: Retrospective, cross-sectional, descriptive study of perioperative allergy, corroborated by skin tests for each drug and latex, of patients treated at the Allergy and Clinical Immunology Department of Hospital General de Mexico. RESULTS: Twenty-eight patients diagnosed with perioperative allergy were included. Main triggers were neuromuscular blocking agents (46.42 %), latex (28.52 %) and propofol (14.28 %). The main risk factor was a history of previous surgeries (89.28 %). Most perioperative allergic reactions were mild (71.42 %) and occurred within the postoperative period (60.71 %). CONCLUSIONS: Initial diagnosis and Treatment should always be carried out by the anesthesiologist or surgeon, who should focus on the withdrawal of possible causative agents.

Antecedentes: Las reacciones de hipersensibilidad perioperatorias constituyen un problema de salud mundial, con una incidencia estimada de uno por cada 100 000 procedimientos y una tasa de mortalidad de 0.1 a 9 %. Los principales factores de riesgo son antecedentes de alergia a otros fármacos, atopia, trastornos psiquiátricos asociados y cirugías previas. Objetivos: Determinar la frecuencia de sensibilización y tipo de medicamentos implicados en la alergia perioperatoria en un hospital de tercer nivel, durante tres años. Método: Estudio retrospectivo, transversal, descriptivo de alergia perioperatoria corroborada mediante pruebas cutáneas a cada medicamento y al látex, de pacientes atendidos en el Servicio de Alergia e Inmunología Clínica del Hospital General de México. Resultados: Se incluyeron 28 pacientes con el diagnóstico de alergia perioperatoria. Los principales desencadenantes fueron los bloqueadores neuromusculares (46.42 %), el látex (28.52 %) y el propofol (14.28 %). El principal factor de riesgo fue el antecedente de cirugías previas (89.28 %). En su mayoría, las reacciones de alergia perioperatoria fueron leves (71.42 %) y se presentaron en el periodo posoperatorio (60.71 %). Conclusiones: El diagnóstico y tratamiento iniciales siempre deberán efectuarse por el médico anestesiólogo o el cirujano, enfocados en el retiro de los posibles agentes causales.