Changes in Prevalence of IgE Sensitization and Allergenic Exposition over a 10-Year Period in a Tropical Region.

INTRODUCTION: Multiple antigen environmental sources have been identified as possible causes of allergies, but few studies have evaluated changes in the sensitization profiles over time. The aim of this study was to evaluate the changes in IgE sensitization and exposure to dust mites, cats, dogs, and cockroaches over a 10-year period. METHODS: During a period of 10 years among patients with asthma, rhinitis and/or atopic dermatitis, we evaluated the annual frequency of atopy to Dermatophagoides farinae, Dermatophagoides pteronyssinus, Blomia tropicalis, Canis familiaris, Felis domesticus and cockroaches (Periplaneta americana and Blatella germanica). Exposure to sources was also assessed using questionnaires (Pets) or direct counts (House dust mites and cockroaches). The association between some risk factors and the prevalence of atopy was explored. RESULTS: A total of 6,000 records were included. Among the patients, 82% had IgE sensitization to at least one of the six allergenic sources. Sensitization to Dermatophagoides spp. was the most frequent (>78%). Exposure and sensitization in the first decade of life to Dermatophagoides spp. seem to determine the molecular spreading to other allergenic sources. Exposure to Blomia tropical increases significantly over time (year 2015; 38% vs. year 2022; 51%, p 0.03). Exposure to dogs was higher than with cats but association between atopy and exposure was stronger with cats (OR 27.4, 95% CI: 22.3-33.6, p < 0.01). CONCLUSION: Exposure and sensitization in the first decade of life to Dermatophagoides spp. determine the molecular spreading of IgE antibodies to other allergenic sources. Household exposure to dogs and cats seems to be important for the subsequent development of atopy. Sensitization to B. tropicalis and cockroach appears to be mostly from cross-reactivity rather than direct exposure.

Diagnostic Performance of IgE Anti-Der p 10 to Identify Patients with Shrimp Allergy.

BACKGROUND: Patients with allergic rhinitis to house dust mites have an increased risk of shrimp allergy. Der p 10 is a candidate biomarker to predict the risk of shrimp allergy among allergic rhinitis patients. OBJECTIVES: The aim of this study was to evaluate the diagnostic performance of anti-Der p 10 IgE as a predictor of shrimp allergy. METHODS: A nested case-control study was carried out with eighty-six allergic rhinitis patients sensitized to mite (Dermatophagoides pteronyssinus) and shrimp (Litopenaeu vannamei). Cases and controls were defined by anti-Der p 10 IgE results. Oral challenge with shrimp was used as the gold standard for the evaluation of diagnostic performance. RESULTS: All shrimp oral challenge test (OCT)-positive patients were positive for IgE against Der p 10. The level of anti-Der p 10 IgE >1.2 kUA/mL had the best diagnostic performance (sensitivity 100%, specificity 65%) Conclusion: Anti-Der p 10 IgE is useful for predicting shrimp allergy diagnosis and could reduce the requirement of an OCT.

[Systemic reaction after performing a food prick-to-prick test. A case report]. / Reacción sistémica desencadenada por una prueba por punción cutánea con alimentos frescos. Informe de un caso.

BACKGROUND: Skin prick test is the most widely used test for the diagnosis of IgE-mediated conditions. Commercial extracts are used for its performance, but in the case of fruits and vegetables it is preferable using fresh food. Although both tests possess a good safety profile, hypersensitivity reactions have been recorded. CLINICAL CASE: Forty-seven-year old woman with a history of persistent allergic rhinitis, sensitized to the pollen of grasses, olive and salsola; she was referred to an allergology department due to anaphylaxis triggered by the consumption of avocado, cantaloupe, carrots and watermelon. Minutes after skin prick test with standardized extract and skin prick with fresh foods, she developed dyspnea, pruritus, erythema, dizziness and sibilance; she was administered 0.5 mg of intramuscular adrenalin and 4 salbutamol inhalations and placed in the Trendelemburg position. Dyspnea persisted, and vital signs monitoring showed heart and respiratory rates increase and, hence, salbutamol was applied again, together with 2 L/min of oxygen delivered by nasal cannula, intravenous fluids and 100 mg intravenous hydrocortisone; improvement was observed at 40 minutes. The patient was hospitalized for 48 hours. CONCLUSIONS: Although skin tests are safe, the risk of hypersensitivity and anaphylactic reactions should not be ruled out, especially in susceptible patients.

Antecedentes: La prueba por punción epidérmica es la principal prueba para el diagnóstico de enfermedades mediadas por IgE. Para su realización se utilizan extractos comerciales; en el caso de frutas y verduras es mejor emplear alimentos frescos. Si bien ambas modalidades poseen un buen perfil de seguridad, se han registrado reacciones de hipersensibilidad. Caso clínico: Mujer de 47 años de edad con antecedentes de rinitis alérgica persistente, sensibilizada a polen de gramíneas, olivo y salsola; fue remitida a un servicio de alergología por anafilaxia desencadenada por el consumo de aguacate, melón, zanahoria y sandía. Minutos después de la punción cutánea con extracto estandarizado y punción cutánea con alimentos frescos, desarrolló disnea, prurito, eritema, mareo y sibilancias. Se le administraron 0.5 mg de adrenalina intramuscular y 4 inhalaciones de salbutamol; también fue colocada en posición de Trendelemburg. La disnea persistió y el monitoreo de los signos vitales mostró incremento de las frecuencias cardiaca y respiratoria, por lo que se aplicó nuevamente salbutamol, 2 L/min de oxígeno por cánula nasal, líquidos endovenosos y 100 mg de hidrocortisona intravenosa; a los 40 minutos se observó mejoría. La paciente fue hospitalizada durante 48 horas. Conclusiones: Aunque las pruebas cutáneas son seguras, no debe excluirse el riesgo de reacciones de hipersensibilidad y anafilaxia, especialmente en pacientes susceptibles.

[Omalizumab: therapeutic option in chronic spontaneous urticaria difficult to control with associated vasculitis, report of three cases]. / Omalizumab: opción terapéutica para la urticaria crónica espontánea de difícil control con vasculitis asociada, reporte de tres casos.

INTRODUCTION: Approximately 50% of chronic urticaria cases do not respond adequately to conventional doses of antihistamines, so a number of other therapeutic options have been suggested. Among these, omalizumab is an innovative tool, which now has high-quality evidence that supports its use in difficult cases, rapidly improving the symptom index and the use of medications with a good safety profile. OBJECTIVE: To report three cases of adult women with spontaneous chronic urticaria with an evolution of more than eight years, which did not improve with high doses of antihistamines and leukotriene receptor blockers, associated with immunomodulatory therapy in which several etiologic mechanisms were combined: chronic spontaneous urticaria with autoimmune and pressure components, and vasculitis. MATERIALS AND METHODS: We report the cases with their clinical and laboratory evaluations, used medication, the response after the start of omalizumab and we performed a review of the literature on the use of this drug in chronic urticaria. RESULTS: In all the presented cases, we obtained complete improvement of symptoms after starting omalizumab. CONCLUSION: Omalizumab is a successful treatment option in cases of difficult to control chronic urticaria with associated vasculitis in which the options proposed by international guidelines have been exhausted.

Omalizumab: opción terapéutica para la urticaria crónica espontánea de difícil control con vasculitis asociada, reporte de tres casos / Omalizumab: therapeutic option in chronic spontaneous urticaria difficult to control with associated vasculitis, report of three cases

Introducción. Aproximadamente el 50 % de los casos de urticaria crónica no mejoran adecuadamente con las dosis convencionales de antihistamínicos, por lo cual se han planteado múltiples opciones terapéuticas, entre las cuales el omalizumab es una herramienta novedosa que ahora cuenta con evidencia de alta calidad que soporta su uso en los casos difíciles, que mejora rápidamente el índice sintomático y el uso de medicamentos, y cuenta con un buen perfil de seguridad. Objetivo. Presentar tres casos de mujeres adultas con urticaria crónica espontánea de más de ocho años de evolución, que no mejoraron con el tratamiento con altas dosis de antihistamínicos, asociados a antileucotrienos e inmunomoduladores y en quienes se combinaban varios mecanismos fisiopatológicos: urticaria crónica espontánea con componente de autoinmunidad, componente de presión y urticaria vasculítica. Materiales y métodos. Se reportan los casos con sus respectivas evaluaciones clínicas y de laboratorio, los medicamentos usados y la respuesta después del inicio de omalizumab y se hace una revisión de la literatura científica sobre uso de este medicamento en la urticaria crónica. Resultados. En los tres casos presentados se obtuvo una mejoría completa de los síntomas tras el inicio del omalizumab. Conclusión. El omalizumab es una opción terapéutica exitosa en casos de urticaria crónica de difícil control con vasculitis asociada, cuando se han agotado las opciones propuestas por las guías internacionales.

Introduction: Approximately 50% of chronic urticaria cases do not respond adequately to conventional doses of antihistamines, so a number of other therapeutic options have been suggested. Among these, omalizumab is an innovative tool, which now has high-quality evidence that supports its use in difficult cases, rapidly improving the symptom index and the use of medications with a good safety profile. Objective: To report three cases of adult women with spontaneous chronic urticaria with an evolution of more than eight years, which did not improve with high doses of antihistamines and leukotriene receptor blockers, associated with immunomodulatory therapy in which several etiologic mechanisms were combined: chronic spontaneous urticaria with autoimmune and pressure components, and vasculitis. Materials and methods: We report the cases with their clinical and laboratory evaluations, used medication, the response after the start of omalizumab and we performed a review of the literature on the use of this drug in chronic urticaria. Results: In all the presented cases, we obtained complete improvement of symptoms after starting omalizumab. Conclusion: Omalizumab is a successful treatment option in cases of difficult to control chronic urticaria with associated vasculitis in which the options proposed by international guidelines have been exhausted.