Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Introduction: tropomyosin is a pan-allergen that shows cross-reactivity between different species. In tropical countries, allergy to arthropods (mites, shrimp, cockroaches, mosquitoes) or nematodes (Ascaris spp) is common. IgE epitopes of tropomyosin may be the source of sensitization and the development of allergic symptoms. However, T epitopes (MHC-II) polarize the Th2 response. Objective: This study aimed to identify by in silico methods tropomyosin consensus B and T epitopes of shrimp species, house dust mites, insects, and nematodes associated with allergic diseases in tropical countries. Methods: in silico analysis included tropomyosin from mites (Der p 10, Der f 10, Blo t 10), insects (Aed a 10, Per a 7, Bla g 7), shrimp (Lit v 1, Pen m 1, Pen a 1), and nematode (Asc l 3); all sequences were taken from the UniProt database. Linear IgE epitopes were predicted with AlgPred 2.0 and validated with BepiPred 3.0. MHC-II binding T cell epitopes were predicted using the IEDB server, which implements nine predictive methods (consensus method, combinatorial library, NN-align-2.3, NN-align-2.2, SMM-align, Sturniolo, NetMHCIIpan -3.1, and NetMHCIIpan -3.2) these predictions focused on 10 HLA-DR and 2 HLA-DQ alleles associated with allergic diseases. Subsequently, consensus B and T epitopes present in all species were identified.  Results: we identified 12 sequences that behaved as IgE-epitopes and B-cell epitopes, three of them: 160RKYDEVARKLAMVEA174, 192ELEEELRVVGNNLKSLEVSEEKAN215, 251KEVDRLEDELV261 were consensus in all species. Eleven peptides (T-epitopes) showed strong binding (percentile rank ≤ 2.0) to HLA-DRB1*0301, *0402, *0411, *0701, *1101, *1401, HLA- DQA1*03:01/DQB1*03:02, and HLA- DQA1*05:01/DQB1*02:01. Only two T-epitopes were consensus in all species: 167RKLAMVEADLERAEERAEt GEsKIVELEEELRV199, and 218EEeY KQQIKT LTaKLKEAEARAEFAERSV246. Subsequently, we identified 2 B and T epitope sequences and reached a consensus between species 167RKLAMVEA174 and 192ELEEELRV199. Conclusions: These data describe three sequences that may explain the IgE cross-reactivity between the analyzed species. In addition, the consensus B and T epitopes can be used for further in vitro investigations and may help to design multiple-epitope protein-based immunotherapy for tropomyosin-related allergic diseases.

Introduction: Multi-epitope vaccines in recent years have shown promising immunomodulatory effects on different alterations of the immune system; being allergic diseases a field to be explored, particularly with house dust mite allergens (HDM) and nematodes such as A. lumbricoides which are common in allergic patients in tropical regions. Objective: the objective of the present study was to design a multi-epitope protein from A. lumbricoides and APD allergens and to evaluate its IgE reactivity preliminarily. Methos: using computational tools, a molecule containing multiple "T" epitopes of allergens derived from A. lumbricoides and APD was designed "in silico" This multi-epitope protein (MP1) was expressed using an E. coli system and purified by affinity chromatography using Ni-NTA agarose. Anti-MP1 and anti-HDM extract IgE reactivity was evaluated by Dot-Blot and indirect ELISA from sera of HDM-allergic patients and non-allergic individuals from Barranquilla-Colombia. Allergic individuals had a positive skin test to a standardized battery of inhaled allergens (EUROLINE - Ref: DP 3704-1601-1 E) and mite-specific IgE. Results: multi-epitope (MP1) protein was expressed and purified with high purity. Dot-Blot result showed that all sera from allergic patients showed lower IgE reactivity to MP1 compared to HDM extract. By ELISA, significantly lower concentrations of anti-MP1 IgE (Median: 270.86 ng/ml; IQR: 90.3) were observed in contrast to anti-HDM IgE levels (Median: 988.5 ng/ml; IQR: 1117.6) in sera of patients allergic to HDM. Conclusions: A protein composed of multiple epitopes of A. lumbricoides and HDM allergens was designed, expressed, and purified. Preliminary Dot-Blot results suggest that this molecule shows hypoallergenic properties with very low IgE reactivity compared to mite extract. Further functional studies are needed to understand better the immune response induced by this molecule.

Objetivo: Identificar, a través de análisis In Silico, el posible mimetismo molecular entre Der p 23 y antígenos de fuentes alergénicas. Métodos: Se buscó identidad entre Der p 23 y proteínas de las familias de ácaros Pyroglyphidae, Acaridae, Chortoglyphidae y Echimyopodidae, a través de PSI-BLAST, y se utilizaron PRALINE y EMBOSS para los alineamientos. Los antígenos con estructura experimental resuelta se obtuvieron de Protein Data Bank, y aquellos no informados, se generaron mediante Swiss Model Server y ALPHAFOLD 2. La predicción de epítopes se realizó con el servidor Ellipro y para la visualización de los modelos en 3D, se utilizó Pymol 2.3. Resultados: El análisis entre alérgenos de Pyroglyphidae y Der p 23, mostró identidad con la proteína parecida a endoquitinasa de D. pteronyssinus, y el dominio de unión a quitina tipo 2 de D. farinae, con identidades entre 85 y 100%, con coberturas de 100% y 75%, respectivamente. Los alérgenos Der f 23 y Der p 23 de D. farinae y D. pteronyssinu,s tuvieron una cobertura del 100% con identidades del 85,42% y 79,59%, respectivamente. Entre los alérgenos de Tyrophagus putrescentiae, se incluyeron la unión a quitina, glicoproteína específica del oviducto y Cda4p, las cuales tuvieron valores de identidad correspondientes al 40%, 42,22% y 34,78%, con valores de cobertura que no superan el 55%. No se encontraron resultados para Chortoglyphidae y Echimyopodidae. Conclusión: Existe mimetismo molecular y homología estructural entre Der P 23 y alérgenos de fuentes alérgicas de las familias Pyroglyphidae y Acaridae. Se identificaron potenciales epítopes en Der p 23, los cuales podrían presentar reactividad cruzada con las proteínas de las fuentes alergénicas estudiadas, lo cual debe ser demostrado en estudios In Vitro e In Vivo. Se necesitan trabajos In Vitro e In Vivo que demuestren los resultados obtenidos en el análisis In Silico.

Objetivo: Evaluar los síntomas persistentes de pacientes con COVID-19 parcial o completamente recuperados de la enfermedad. Métodos: Estudio observacional, descriptivo, transversal y prospectivo, llevado a cabo en pacientes con antecedente de infección por SARS-CoV-2, de cualquier edad y género, que voluntariamente contestaran una encuesta después de padecer la infección, con la intención de identificar los signos y síntomas asociados. Para evaluar si los síntomas se asociaban con el género femenino, obesidad o edad y el síndrome post-COVID se utilizaron las pruebas X2 y t de Student para muestras independientes. Resultados: Se registraron 197 pacientes, con promedio de edad de 41.57 años (DE: 14.2 años), 61.9% fueron mujeres. El síndrome post-COVID apareció en el 52.3% de los casos. La depresión, anosmia, disgeusia, nausea, alopecia y trastornos de la conducta fueron significativamente más frecuentes en las mujeres. La artralgia, disnea, tos y odinofagia mostraron significación estadística en pacientes con obesidad (p <0.05) Conclusión: Se calculó una frecuencia del 52.3% de síndrome post-COVID, con una variedad de signos y síntomas. Las mujeres tuvieron mayor riesgo de padecer el síndrome post-COVID, con síntomas como: depresión, trastornos de la conducta, anosmia y alopecia. Palabras clave: COVID-19; Síndrome post-COVID; SARS-CoV-2; Obesidad; Depresión; Trastornos de la conducta.

Objetivo: Determinar la prevalencia de rinitis alérgica e identificar los aeroalérgenos más frecuentes por medio de pruebas de reactividad cutánea en pacientes pediátricos y adultos con rinitis alérgica. Métodos: Estudio observacional, transversal y retrospectivo, llevado a cabo a partir del análisis de expedientes clínicos de pacientes con pruebas cutáneas, con la finalidad de identificar, de forma intencionada, signos y síntomas de rinitis alérgica, así como aeroalérgenos a los reaccionaron positivamente. Resultados: Se revisaron 1531 pruebas de reactividad cutánea, de las que 983 correspondieron a pacientes con diagnóstico de rinitis alérgica con prueba positiva. La prevalencia de la enfermedad fue del 64.2% (n = 983); la población pediátrica tuvo una prevalencia del 55.8% (n = 549) y la adulta del 44.1% (n = 434). Los aeroalérgenos con mayor frecuencia de sensibilización fueron: Dermatophagoides pteronyssinus (59.5%), Dermatophagoides farinae (45.3%), gato (26.1%), Cupressus arizónica (21.7%), perro (21.6%) y Fraxinus excelsior ([Fresno, Ash], 19.6%). Conclusión: Existe elevada prevalencia de rinitis alérgica en la cohorte estudiada. Los ácaros del polvo doméstico Dermatophagoides mix (Pteronyssinus y Farinae) fueron os principales alérgenos. La cosensibilización a gato y perro fue alta. Las especies de polen arbóreo con mayor repercusión fueron: Cupressus arizónica, Fraxinus excelsior y Quercus robur (Roble, Encino, Oak). Las variedades de polen de pasto con mayor influencia: Cynodon dactylon (Bermuda, Capriola) y Lolium Perenne (Pasto inglés). Palabras clave: Alérgenos; Rinitis alérgica; Prevalencia; Pruebas cutáneas; México.

Background: Non-IgE-mediated gastrointestinal food allergy includes adverse reactions to food mediated by the innate immune system and cellular immunity. It is characterized by subacute or chronic gastrointestinal symptoms after ingestion of a relevant food allergen, making diagnosis difficult. Objective: To carry out an updated bibliographic review of non-IgE-mediated gastrointestinal food allergy, that summarizes incidence, pathophysiology, clinical manifestations, diagnostic tools and treatment. Methods: A search was conducted in the databases Medline, EMBASE, Scielo, Google Scholar and the Advanced Medicine Informatics Network (RIMA) using the keywords: non-IgE-mediated food allergy, allergic proctocolitis; cow’s milk-induced anemia; food protein-induced enteropathy; food protein-induced enterocolitis syndrome; Celiac disease and Heiner syndrome. The search was limited to articles published in English and Spanish from January 2015 to May 2024. Results: While progress has been made in the recognition of these diseases, the prevalence and pathophysiology remain uncertain. Involvement of the innate immune system and cellular immunity in gastrointestinal inflammation has been found, but further studies are needed to clarify the immunopathogenesis and associated biomarkers. Conclusions: Non-IgE-mediated gastrointestinal food allergy account for an unknown proportion of food allergies. Since there are no biomarkers or non-invasive confirmatory tests, the diagnosis relies on clinical features and is confirmed when the symptoms improve with elimination of the offending food. Management includes avoidance of the causative food from the diet, supportive treatment in case of accidental exposure, and nutritional counseling. Keywords: Non-IgE-mediated food allergy; Food protein-induced enterocolitis syndrome; Celiac disease; Allergic proctocolitis; Cow’s milk-induced anemia; Food protein-induced enteropathy; Heiner syndrome.

Objectives: To evaluate the prevalence of methylisothiazolinone (MI) sensitivity and associated factors in individuals with suspected allergic contact dermatitis. Methods: Cross-sectional study based on patch tests, including methylisothiazolinone 0.2%, in 286 participants with suspected allergic contact dermatitis, in Brasília/DF, Brazil, between March/2020 and March/2022. Results: 13.6% of participants were diagnosed with allergic contact dermatitis and sensitive to MI. The mean age was 43.7 years, and the majority were women (71,8%). The average duration of the disease was 60 months. The most common location was hands (76.9%) and upper limbs (33.3%). In 97.4%, allergy to methylisothiazolinone was considered of current relevance. In the multivariate model, being domestic/household increased the chance of presenting sensitivity to MI by 4.2 (95% CI= 1.36 - 13.5). Presenting lesions in several places of the body was also significantly associated (OR=2.84; CI 95%=1.17 - 6.86) to be sensitive to the test substance. Conclusion: The findings confirm the epidemic of allergy to methylisothiazolinone. They reinforce the need for the inclusion of this isolated substance in the Brazilian baseline series. We emphasize the need for regulations on the use of methylisothiazolinone in industrial products and household detergents, as is done for cosmetics. Studies in other centers are needed to confirm these results. Keywords: Prevalence; Methylisothiazolinone; Allergic contact dermatitis; Allergy; Epidemiology; Detergents; Industrial products.  

Objetivo: Determinar la prevalencia de rinitis alérgica en niños escolares. Métodos: Estudio transversal y descriptivo, llevado a cabo en niños de 6 a 10 años, a quienes se efectuaron pruebas cutáneas (ácaros, pólenes, hongos, cucaracha, pelo de perro y gato). El diagnóstico de rinitis alérgica se estableció con base en la prueba recomendada por la EuropeanAcademy of Allergy and ClinicalInmunology (EAACI) y el American College of Allergy, Asthma and Inmunology (ACAAI) para alergia mediada por IgE alérgeno específica. El análisis estadístico incluyó intervalo de confianza para promedios y porcentajes. Resultados: Se registraron 992 pacientes. La prevalencia de rinitis alérgica fue del 15.7% (IC95%: 13.4-18.0), el síntoma más predominante fue rinorrea hialina en 94.7% (IC95%: 91.4-94.6), y los principales alérgenos: ácaros del polvo 60.4% (IC95%: 52.7-68.1) y pólenes 59.3% (IC95%: 51.6-67.0). Conclusión: La prevalencia de rinitis alérgica en niños escolares, diagnosticados mediante pruebas cutáneas, fue del 15.7%, principalmente en varones (63.1%). Palabras clave: Rinitis alérgica; Pruebas cutáneas; Prevalencia; IgE alérgeno específica; Rinorrea hialina; Ácaros del polvo; Pólenes.

Background: Ixekizumab is a high-affinity IgG4 monoclonal humanized antibody useful for the treatment of ankylosing spondylitis. Benign skin reactions are a common adverse event with ixekizumab but systemic hypersensitivity reactions are much more unusual. Case report: We describe the case of a 54-female patient with HLAB27+ spondyloarthritis. Treatment with ixekizumab 80 mg subcutaneous (containing polysorbate) was prescribed. The patient experienced immediate severe dyspnea, skin erythema and flushing. Intradermal test (0.8 mg/ml) was clearly positive in the immediate reading. The patient was planned to undergo ixekizumab desensitization according to an 8-step protocol with good tolerance. Conclusion: We report a patient with HLAB27+ spondyloarthritis treated with ixekizumab who developed a systemic IgE-mediated reaction. A successful and easy to perform subcutaneous desensitization protocol is described. Keywords: Hypersensitivity; Ixekizumab; Systemic reaction; Skin test; Desensitization protocol.

We read with interest the article by Cano-Salas et al (1), who aim to determine the annual economic burden of the disease from an institutional perspective using GINA's recommended classification in a retrospective cohort of adults treated at Mexico City's Instituto Nacional de Enfermedades Respiratorias (INER). We value the authors' efforts. However, we would like to express our criticisms of the authors' work. The authors stated that they estimated the cost using INER's 2020 unitary costs, which correspond to the amounts charged to patients. The distinction between cost and charge is critical in medical economics because it ensures the consistency of all analyses. Cost refers to the amount paid by the producer, usually a hospital, for resources used during the production process, such as outpatient visits and hospitalization. Charge, on the other hand, represents the fee levied on the consumer, typically the patient, in order for the institution to achieve financial equilibrium and solvency (2). Given these inherent differences, actual resource consumption should serve as a cost metric (3). Direct cost allocation necessitates elaborate processes of identification, measurement, and valuation (4). Direct costs are financial outlays for resources directly related to medical activities, and they are commonly classified as fixed or variable (2,5). Fixed costs, such as rent and taxes, do not change regardless of activity level, whereas variable costs, such as supplies, rise in proportion to activity, with each additional patient incurring incremental variable costs (6). Given the complexities of cost estimation management, it is critical to grasp the subtle distinctions between cost and charge. Moving forward, an in-depth understanding of direct medical costs and allocation methodologies is required for accurate financial analysis and resource allocation in chronic disease management.