Subcutaneous allergen immunotherapy for asthma: A randomized, double-blind, placebo-controlled study with a standardized Blomia tropicalis vaccine.

BACKGROUND: Sensitization to Blomia tropicalis (Bt) is very frequent in the tropics, and particularly in Cuba, being a significant cause of allergic asthma. Allergen immunotherapy (AIT) with Bt can be a therapeutic option, however, placebo-controlled clinical trials have not been reported. OBJECTIVE: To assess the therapeutic effect and safety of AIT for asthma using a standardized allergen vaccine of B. tropicalis by subcutaneous route, in allergic asthmatic patients exposed and sensitized to this mite species. METHODS: A double-blind, placebo-controlled Phase II trial was conducted in 35 adults (18 with treatment and 17 with placebo), with mild to moderate asthma, predominantly sensitized to Bt. AIT was administered subcutaneously in increasing doses from 4 to 6000 Biological Units using a locally manufactured standardized extract (BIOCEN, Cuba). Patient assessment was performed using symptom-medication score (SMS), peak expiratory flow and skin reactivity relative to Histamine as measured by skin prick test (SPT). RESULTS: The 12-month treatment achieved a significant (p < 0.001) decrease of SMS. Symptom score showed only 41% (CI: 26-61) of placebo values, whereas medication was 34.5% (22.4%-63.3%). Treatment was regarded clinically effective in 67% of patients (OR 32; 95%CI: 17 to 102). The effect size on symptoms and medication was higher than has been reported with equivalent allergen dosages of D. pteronyssinus and D. siboney in Cuban asthmatic patients. Skin reactivity to Bt was also significantly reduced (p = 0.0001), increasing 148-fold the allergen threshold to elicit a positive skin test. This desensitization effect was specific to Bt and did not modify the reactivity to Dermatophagoides. The change of specific skin reactivity was significantly (p < 0.05) correlated to clinical improvement. All adverse events were local with a frequency of 2.4% of injections. CONCLUSIONS: Subcutaneous AIT with Blomia tropicalis was effective and safe in asthmatic adults exposed and sensitized to this mite species in a tropical environment. TRIAL REGISTRATION: Cuban Public Registry of Clinical Trials: RPCEC00000026 (WHO International Clinical Trial Registry Platform ICTRP).

[Sensitivity and specificity of prick skin test with two concentrations of standardized extract of Culex quinquefasciatus in allergic children]. / Sensibilidad y especificidad de la prueba cutánea por punción con dos concentraciones del extracto estandarizado de Culex quinquefasciatus en niños alérgicos.

BACKGROUND: Diagnostic options for immune reactions to mosquito bites are limited. In Cuba, IgE-mediated reactions are frequently related to Culex quinquefasciatus bite. OBJECTIVE: To determine the sensitivity and specificity of skin prick test with two doses of standardized extract in nitrogen protein units (PNU of Culex quinquefasciatus (BIOCEN, Cuba). MATERIAL AND METHOD: An analytical study was conducted on 100 children between 2 and 15 years old. Fifty atopic patients with a history of allergy to mosquito bite and positive specific serum IgE Culex quinquefasciatus and fifty atopic patients without a history of allergy to mosquito bite and negative specific serum IgE to Culex quinquefasciatus. Skin prick tests (SPT) were performed by duplicates on the forearms of the patients. Investigated doses were 100 PNU/mL and 10 PNU/mL. RESULTS: SPT with the highest concentration obtained a mean wheal size of 22.09 mm2 and for lower doses of 8.09 mm2, a statistically significant difference (p=0.001, Student's t test). Positive skin test correlated in 100% of patients with the presence of specific IgE. Testing with both doses showed a 94% of specificity and 88% of sensitivity. CONCLUSION: The diagnostic accuracy of SPT using both doses of standardized extract was similar, which justifies its use for diagnosis of sensitization to Culex quinquefasciatus in patients with symptoms of allergy to mosquito bite.

Antecedentes: las opciones diagnósticas de las reacciones inmunológicas a la picadura del mosquito son limitadas. En Cuba, las reacciones mediadas por IgE más frecuentes son por picadura de Culex quinquefasciatus. Objetivo: determinar la sensibilidad y especificidad de la prueba cutánea por punción con dos dosis del extracto estandarizado en unidades de nitrógeno proteico (UNP) de Culex quinquefasciatus (BIOCEN, Cuba). Material y método: estudio analítico efectuado en 100 niños entre 2 y 15 años de edad: 50 pacientes atópicos con antecedentes de alergia a la picadura de mosquito e IgE sérica específica positiva a Culex quinquefasciatus y 50 pacientes atópicos sin antecedentes de alergia a la picadura de mosquito e IgE sérica específica negativa a Culex quinquefasciatus. La prueba cutánea por punción se realizó por duplicado en los antebrazos de los pacientes. Las dosis investigadas fueron 100 y 10 UNP/mL. Resultados: en la prueba cutánea por punción con el extracto de mayor concentración se obtuvo un tamaño del área del habón de 22.09 mm2 y con la menor concentración de 8.19 mm2; una diferencia estadísticamente significativa (p=0.001, prueba t de Student). La prueba cutánea positiva se correlacionó en el 100% de los pacientes con la existencia de IgE específica. La prueba con ambas dosis mostró 94% de especificidad y 88% de sensibilidad. Conclusión: la alta coincidencia en el resultado de la prueba cutánea nos muestra que puede sustituirse la concentración del extracto a 100 UNP/mL por la de menor concentración, sin perder confiabilidad en el diagnóstico de sensibilización al mosquito Culex quinquefasciatus, utilizando ese método in vivo.

Desensibilización con aspirina en un paciente con intolerancia a antiinflamatorios no esteroides / Aspirin desensitization in a patient who exhibit intolerance to non-steroidal anti-inflammatories

El ácido acetilsalicílico o aspirina es uno de los medicamentos más utilizados a nivel mundial. Los pacientes con enfermedad coronaria requieren tratamientos prolongados con este medicamento, el cual se les niega a aquellos con historias de reacciones adversas a este. Se recoge en la literatura internacional el uso de terapias de desensibilización en pacientes con intolerancia a los antiinflamatorios no esteroides con diferentes protocolos, con resultados satisfactorios. En este trabajo se describe la primera desensibilización con aspirina realizada a un paciente en el Hospital Universitario Calixto García y el protocolo de actuación utilizado. No se encontró otro caso en la bibliografía nacional. El paciente actualmente ingiere 125 mg diarios sin reacciones adversas. Se considera que la desensibilización con aspirina es una opción terapéutica efectiva en aquellos pacientes con intolerancia a esta y con una afección que justifique este proceder

Aspirine is one of the most widely used drugs worldwide. The patients suffering from heart diseases require long-term treatment with this drug, which is banned to those having adverse reactions. The international literature collects information on the use of desensitization therapies in patients who do not exhibit tolerance to this medicine, following different protocols with satisfactory results. This paper described the first aspirin desensitization procedure, which was performed at Calixto García university hospital, and the performance protocol. There was not any other case of this type reported in the national literature. The patient can presently take 125 mg of aspirin daily without suffering adverse events. It was considered that the desensitization process is an effective therapeutic action for patients who are aspirin sensitive and who have specific diseases that warrant this procedure

[Comparison of two lancets in the skin prick test]. / Comparación de dos lancetas en la prueba cutanea por punción.

BACKGROUND: The skin prick test is used to diagnose the allergic sensitization. Its results depend upon several factors, such as the lancet type. In Cuba, the most frequently used are: ALK lancet and blood lancet. OBJECTIVE: To compare these two lancets regarding the size of the wheal, precision, sensitivity and specificity of the skin prick test and, finally, the preference of the patients to one of them. PATIENTS AND METHODS: The study was performed in 60 allergic patients, aged 15-50 years, seen at the allergy service of Hospital Universitario Clínico Quirúrgico General Calixto García. The skin prick test was performed on the forearm of all patients included, using both lancet types. A negative control (diluent solution) was applied, together with a 54.3 mmol/L histamine solution in five replicates. RESULTS: The mean size of skin reaction to histamine was 6 mm, using a 1 mm single peak lancet (ALK), size was 6.5 mm when using blood lancet (significant difference p < 0.05). Precision, sensitivity and specificity of ALK lancet were 9.7, 100 and 100%, respectively. On the other hand, the respective values for blood lancet were 15.9, 96 and 87%. Of those studied, 27% presented mild pain and 3% moderate pain using the ALK lancet; while 25% showed mild pain and 10% moderate pain using the blood lancet. CONCLUSION: The ALK lancet showed more precision, sensitivity and specificity and it was preferred by the patients.

Rinitis alérgica y rinosinusitis: una revisión necesaria / Allergic rhinitis and rhinosinusitis: a necessary review

La importancia de las enfermedades alérgicas, y entre ellas de la rinitis alérgica, así como su costo económico y de recursos humanos, tanto como su prevalencia, está fuera de toda duda. Esta entidad representa la sexta causa de enfermedad crónica en EE.UU. y tiene un gran impacto en la calidad de vida de los pacientes que la padecen. La rinitis alérgica es un desorden heterogéneo y su alta prevalencia es aún subdiagnosticada. Está caracterizada por uno o más de los siguientes síntomas: estornudos, picor nasal, secreción y congestión nasal. Muchos agentes están involucrados con esta entidad, entre ellos, pólenes, hongos, ácaros y animales domésticos. Atendiendo a que la rinitis y la sinusitis mantienen síntomas en común como la pérdida del olfato y la obstrucción y el drenaje nasal, se prefiere denominarla como rinosinusitis. Muchos estudios han identificado a la rinitis como un factor de riesgo para el asma, con una prevalencia entre 80 y 90 por ciento. Esta revisión pretende repasar aspectos fundamentales de estas entidades como definición, etiología, clasificación, síntomas y tratamiento, y servir de guía para aquellos médicos que de una forma u otra tratan ambas afecciones con un impacto demostrado en la calidad de vida de los que las padecen