SEAIC Specialty Forum: Analysis of the Current Situation of Allergology in Spain and Outlook for the Future.

BACKGROUND AND OBJECTIVES: Allergology has been a recognized medical specialty in Spain, with fully defined aims and competencies for more than 4 decades. However, in recent years, its visibility seems to have decreased somewhat. Objectives: To identify which specific factors have contributed to the waning of the importance of the specialty and find tangible solutions to consolidate its place as a front-line medical specialty. MATERIAL AND METHODS: An online population survey comprising 60 items of interest was prepared. The degree of agreement and the level of satisfaction with each item were assessed, and implementable initiatives in the short, medium, and long terms were defined in order to provide solutions to the issues identified. RESULTS: The survey was completed by a total of 167 specialists with an average of 18 years' experience. Most were from public reference hospitals, and 29.3% were heads of department. The line of action for which a good degree of agreement was achieved was to promote the inclusion of an allergist in multidisciplinary teams. The priority lines of action were to improve undergraduate and graduate training in allergology and specialized nursing, to identify curricula in Spain, and to develop robust teaching projects. CONCLUSIONS: The results revealed a high degree of homogeneity between professionals. The basic pillars highlighted were as follows: quality training, knowledge, and research in immunotherapy; an innovative portfolio of services endorsed by clinical practice guidelines; and presence in multidisciplinary teams and relevant hospital committees.

SEAIC Specialty Forum: Analysis of the Current Situation of Allergology in Spain and Outlook for the Future

Background: Allergology has been a recognized medical specialty in Spain, with fully defined aims and competencies for more than 4 decades. However, in recent years, its visibility seems to have decreased somewhat. Objectives: To identify which specific factors have contributed to the waning of the importance of the specialty and find tangible solutions to consolidate its place as a front-line medical specialty. Material and methods: An online population survey comprising 60 items of interest was prepared. The degree of agreement and the level of satisfaction with each item were assessed, and implementable initiatives in the short, medium, and long terms were defined in order to provide solutions to the issues identified. Results: The survey was completed by a total of 167 specialists with an average of 18 years’ experience. Most were from public reference hospitals, and 29.3% were heads of department. The line of action for which a good degree of agreement was achieved was to promote the inclusion of an allergist in multidisciplinary teams. The priority lines of action were to improve undergraduate and graduate training in allergology and specialized nursing, to identify curricula in Spain, and to develop robust teaching projects. Conclusions: The results revealed a high degree of homogeneity between professionals. The basic pillars highlighted were as follows: quality training, knowledge, and research in immunotherapy; an innovative portfolio of services endorsed by clinical practice guidelines; and presence in multidisciplinary teams and relevant hospital committees. (AU)

Antecedentes: En nuestro país, la alergología constituye una especialidad médica reconocida con fines y competencias completamente definidos desde hace más de cuatro décadas. Sin embargo, en los últimos tiempos parece hacer frente a una cierta disminución de su visibilidad y reconocimiento. Objetivos: Identificar qué factores específicos contribuyen a esta dilución de su peso específico y buscar soluciones tangibles que la afiancen como especialidad médica de primera línea. Material y métodos: Se elaboró una encuesta poblacional online compuesta por 60 ítems considerados de interés. Se valoró el grado de acuerdo y el nivel de satisfacción con cada uno, definiendo iniciativas implantables a corto, medio y largo plazo que aporten soluciones para las cuestiones identificadas. Resultados: La encuesta fue respondida por un total de 167 especialistas con una media de 18 años de experiencia, la mayoría procedentes de hospitales de referencia públicos, siendo un 29,3% jefes del servicio. La línea de acción que obtuvo un mayor grado de acuerdo fue promover la presencia del alergólogo en los equipos multidisciplinares. Como línea de acción más prioritaria se seleccionó mejorar la formación de pregrado y posgrado en alergología, así como la de enfermería especializada, identificando planes de estudio en nuestro país y elaborando proyectos docentes robustos. Conclusiones: Los resultados revelaron un elevado grado de homogeneidad entre los profesionales, destacando como pilares básicos la formación de calidad, los conocimientos e investigación en inmunoterapia, una cartera de servicios novedosa avalada por Guías de Práctica Clínica y la presencia en equipos multidisciplinares y comisiones hospitalarias relevantes. (AU)

Benralizumab: A New Approach for the Treatment of Severe Eosinophilic Asthma.

Eosinophilic asthma is the most common phenotype of severe asthma. It is characterized by abnormal production and release of type 2 cytokines from T helper type 2 (TH2) lymphocytes and type 2 innate lymphoid cells, such as IL-5. This leads to a persistent increase and activation of eosinophils in blood and the airways despite treatment with high-dose inhaled corticosteroids. Eosinophil differentiation, survival, and activation are preferentially regulated by IL-5, a cytokine that binds to the IL-5 receptor (IL-5R), which is located on the surface of eosinophils or basophils and plays a critical role in the pathogenesis and severity of asthma. Benralizumab is a monoclonal antibody that binds to IL-5R via its Fab domain, blocking the binding of IL-5 to its receptor and resulting in inhibition of eosinophil differentiation and maturation in bone marrow. In addition, this antibody is able to bind through its afucosylated Fc domain to the RIIIa region of the Fcy receptor on NK cells, macrophages, and neutrophils, thus strongly inducing antibody-dependent, cell-mediated cytotoxicity in both circulating and tissue-resident eosinophils. This double function of benralizumab induces almost complete fast and maintained depletion of eosinophils that is much greater than that induced by other monoclonal antibodies targeting the IL-5 pathway, such as mepolizumab and reslizumab. This review focuses on benralizumab as an alternative to other agents targeting the IL-5 pathway in the treatment of eosinophilic asthma.

Benralizumab: a new approach for the treatment of severe eosinophilic asthma

Eosinophilic asthma is the most common phenotype of severe asthma. It is characterized by abnormal production and release of type 2 cytokines from T helper type 2 (TH2) lymphocytes and type 2 innate lymphoid cells, such as IL-5. This leads to a persistent increase and activation of eosinophils in blood and the airways despite treatment with high-dose inhaled corticosteroids. Eosinophil differentiation, survival, and activation are preferentially regulated by IL-5, a cytokine that binds to the IL-5 receptor (IL-5R), which is located on the surface of eosinophils or basophils and plays a critical role in the pathogenesis and severity of asthma. Benralizumab is a monoclonal antibody that binds to IL-5R via its Fab domain, blocking the binding of IL-5 to its receptor and resulting in inhibition of eosinophil differentiation and maturation in bone marrow. In addition, this antibody is able to bind through its afucosylated Fc domain to the RIIIa region of the Fcgamma receptor on NK cells, macrophages, and neutrophils, thus strongly inducing antibody-dependent, cell-mediated cytotoxicity in both circulating and tissue-resident eosinophils. This double function of benralizumab induces almost complete fast and maintained depletion of eosinophils that is much greater than that induced by other monoclonal antibodies targeting the IL-5 pathway, such as mepolizumab and reslizumab. This review focuses on benralizumab as an alternative to other agents targeting the IL-5 pathway in the treatment of eosinophilic asthma

El asma eosinofílica es el fenotipo más común del asma grave. Se caracteriza por una producción y liberación anómala de citocinas de tipo 2, como la IL-5, por los linfocitos T colaboradores de tipo 2 (Th2) y las células linfoides innatas de tipo 2 (ILC-2). Con ello se activan los eosinófilos y se incrementa su número en sangre y vías respiratorias, a pesar del tratamiento con dosis altas de corticosteroides inhalados. La diferenciación, supervivencia y activación de los eosinófilos está regulada principalmente por la IL-5, una citocina que se une a su receptor (IL-5R), situado en la superficie de eosinófilos y basófilos, y que desempeña un papel fundamental en la patogénesis y gravedad del asma. El benralizumab es un anticuerpo monoclonal que se une al IL-5R a través de su dominio Fab, bloqueando la unión de la IL-5 a su receptor, lo que provoca una inhibición de la diferenciación y maduración de los eosinófilos en la médula ósea. Además, este anticuerpo es capaz de unirse a través de su dominio Fc afucosilado a la región RIIIa del receptor Fcgamma situado en células NK, macrófagos y neutrófilos, induciendo así una intensa citotoxicidad mediada por células dependiente de anticuerpos (ADCC), tanto de los eosinófilos circulantes como de los residentes en tejidos. Esta doble función del benralizumab induce una disminución casi completa de los eosinófilos de una forma rápida y mantenida, mucho mayor a la inducida por otros anticuerpos monoclonales dirigidos contra la IL-5, como el mepolizumab o el reslizumab. Esta revisión se centra en describir el uso del benralizumab en el tratamiento del asma eosinofílica como una alternativa a otros agentes que actúan directamente sobre la IL-5

Adherence to Anaphylaxis Guidelines: Real-World Data From the Emergency Department of a Tertiary Hospital.

BACKGROUND AND OBJECTIVE: Few studies have evaluated adherence to anaphylaxis guidelines in emergency departments (EDs). Objective: The objective of this study was to evaluate adherence to anaphylaxis guidelines in the ED of a tertiary hospital. METHODS: Medical records of patients attended in the ED of University Hospital of Salamanca, Spain were reviewed. Those patients fulfilling the anaphylaxis criteria proposed by the NIAID/FAAN were selected. RESULTS: During a 1-year period, we identified 89 patients (74 adults and 15 children). The anaphylactic reaction was moderate in 65% of adults, severe in 34%, and very severe in 1%. In children, all reactions were moderate. Fewer than half of the patients (42%) received adrenaline in the ED; this was administered intramuscularly in only 19% of cases. As for the severity of the reaction, 65% of patients with moderate reactions and 42% with severe reactions were not treated with adrenaline. At discharge from the ED, an adrenaline auto-injector was recommended to only 5.6% of patients. Fifty-two percent of patients received a documented allergy referral (57% adults vs 27% children, P=.047), 29% instructions about avoidance of triggers (31% adults vs 20% children, NS), and 51% written instructions for recognition of anaphylaxis warning signs (41% adults vs 100% children, P<.001). CONCLUSIONS: The results of the study show a large discrepancy between recommendations in guidelines and management of anaphylaxis in the ED. Additional training efforts are needed to improve the treatment of patients with anaphylactic reactions.

Adherence to anaphylaxis guidelines: real-world data from the emergency department of a tertiary hospital

Background: Few studies have evaluated adherence to anaphylaxis guidelines in emergency departments (EDs). Objective: The objective of this study was to evaluate adherence to anaphylaxis guidelines in the ED of a tertiary hospital. Methods: Medical records of patients attended in the ED of University Hospital of Salamanca, Spain were reviewed. Those patients fulfilling the anaphylaxis criteria proposed by the NIAID/FAAN were selected. Results: During a 1-year period, we identified 89 patients (74 adults and 15 children). The anaphylactic reaction was moderate in 65% of adults, severe in 34%, and very severe in 1%. In children, all reactions were moderate. Fewer than half of the patients (42%) received adrenaline in the ED; this was administered intramuscularly in only 19% of cases. As for the severity of the reaction, 65% of patients with moderate reactions and 42% with severe reactions were not treated with adrenaline. At discharge from the ED, an adrenaline auto-injector was recommended to only 5.6% of patients. Fifty-two percent of patients received a documented allergy referral (57% adults vs 27% children, P=.047), 29% instructions about avoidance of triggers (31% adults vs 20% children, NS), and 51% written instructions for recognition of anaphylaxis warning signs (41% adults vs 100% children, P<.001). Conclusion: The results of the study show a large discrepancy between recommendations in guidelines and management of anaphylaxis in the ED. Additional training efforts are needed to improve the treatment of patients with anaphylactic reactions

Antecedentes: Pocos estudios han evaluado el cumplimiento de las recomendaciones de las guías clínicas de anafilaxia en los servicios de urgencias. Objetivo: El objetivo de este estudio fue conocer el cumplimiento de las guías de anafilaxia en el servicio de urgencias (SU) de un hospital terciario. Métodos: Se revisaron los informes de los pacientes atendidos en el SU del Hospital Universitario de Salamanca durante un año y se seleccionaron los que cumplían los criterios de anafilaxia propuestos por el NIAID/FAAN. Resultados: Se identificaron 89 pacientes, 74 adultos y 15 niños. El 65% de los adultos presentó una reacción moderada, el 34% grave y el 1% muy grave; en todos los niños la gravedad fue moderada. Menos de la mitad de los pacientes (42%) fueron tratados con adrenalina, solo el 19% por vía intramuscular. El 65% de las reacciones moderadas y el 42% de las graves no recibieron adrenalina. Al alta, se recomendó un auto-inyector de adrenalina al 5,6% de los pacientes, se remitió al Servicio de Alergia al 52% (57% adultos frente a 27% niños, p=0,047), se dieron indicaciones para evitar posibles desencadenantes al 29% (31% adultos frente a 20% niños, p=.5) e instrucciones para reconocer los signos de alarma de una reacción anafiláctica al 51% (41% adultos frente a 100% niños, P<0,001). Conclusión: Los resultados del estudio muestran importantes discrepancias entre las recomendaciones de las guías clínicas y el manejo de la anafilaxia en un SU hospitalario. Es necesario un mayor esfuerzo en educación para mejorar el tratamiento de los pacientes con anafilaxia

The prostaglandin D2 receptor (PTGDR) gene in asthma and allergic diseases

The prostaglandin D2 receptor (PTGDR) gene has been associated to asthma and related phenotypes by linking and association studies. Functional studies involving animal models and other expression studies based on in vitro cell models also point to a possible role of polymorphisms in the promoter region, in the differential binding of transcription factors, and thus in PTGDR expression, which appear to be associated to the development of asthma or of susceptibility to the disease

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The prostaglandin D2 receptor (PTGDR) gene in asthma and allergic diseases.

The prostaglandin D2 receptor (PTGDR) gene has been associated to asthma and related phenotypes by linking and association studies. Functional studies involving animal models and other expression studies based on in vitro cell models also point to a possible role of polymorphisms in the promoter region, in the differential binding of transcription factors, and thus in PTGDR expression, which appear to be associated to the development of asthma or of susceptibility to the disease.

Airborne pollen calendar of Salamanca, Spain, 2000–2007

Background: The determination of pollen types and their proportions in the atmosphere of relevant urban areas have increasingly been evaluated in different regions. The final goal has been to elaborate a pollen calendar, providing data about the occurrence of pollen grains in the air, thus permitting medical treatment and prophylaxis. Methods: An aerobiological study was carried out in the atmosphere of the city of Salamanca, Spain, during eight years (2000–2007) by means of a Hirst type volumetric spore trap. A pollen calendar was elaborated following exponential classes obtained from 10-day average concentrations of the main pollen types. Results: Mean annual pollen index was 16,916, coming from 72 different types of pollen. During the studied period, an increase of annual pollen levels was registered by means of regression analysis index. The most important types of pollen were Quercus, Poaceae, Cupressaceae, Olea, and Plantago. Arboreal pollen grains (62.7%) were more represented in airborne pollen spectrum than non-arboreal pollen (37.3%). Airborne pollen levels were particularly high between April and July, showing the highest values in May and June. Conclusions: In aerobiological terms Poaceae pollen seems to be a major risk for potential sensitised individuals due to its known allergenicity and its high atmospheric concentrations between late spring and early summer, followed by Cupressaceae, Olea and Platanus pollen grains, and taking into account the possible role of Fraxinus and Quercus in earl spring allergenic courses and in processes of cross-sensitivity, respectively

Airborne pollen calendar of Salamanca, Spain, 2000-2007.

BACKGROUND: The determination of pollen types and their proportions in the atmosphere of relevant urban areas have increasingly been evaluated in different regions. The final goal has been to elaborate a pollen calendar, providing data about the occurrence of pollen grains in the air, thus permitting medical treatment and prophylaxis. METHODS: An aerobiological study was carried out in the atmosphere of the city of Salamanca, Spain, during eight years (2000-2007) by means of a Hirst type volumetric spore trap. A pollen calendar was elaborated following exponential classes obtained from 10-day average concentrations of the main pollen types. RESULTS: Mean annual pollen index was 16,916, coming from 72 different types of pollen. During the studied period, an increase of annual pollen levels was registered by means of regression analysis index. The most important types of pollen were Quercus, Poaceae, Cupressaceae, Olea, and Plantago. Arboreal pollen grains (62.7%) were more represented in airborne pollen spectrum than non-arboreal pollen (37.3%). Airborne pollen levels were particularly high between April and July, showing the highest values in May and June. CONCLUSIONS: In aerobiological terms Poaceae pollen seems to be a major risk for potential sensitised individuals due to its known allergenicity and its high atmospheric concentrations between late spring and early summer, followed by Cupressaceae, Olea and Platanus pollen grains, and taking into account the possible role of Fraxinus and Quercus in early spring allergenic courses and in processes of cross-sensitivity, respectively.

Interactions between genes and the environment. Epigenetics in allergy.

Epigenetics is defined as those inheritable changes occurring in gene expression, without actual modification in the genic DNA sequence. Epigenetic factors are chemically stable, potentially reversible, and can be modulated or induced by environmental factors. In the case of allergic disease, epigenetics could explain not only the discordances observed between monozygous twins but also phenomena such as incomplete penetrance, variable expression, gender and progenitor effects, and sporadic cases. In this sense, the hypothesis of hygiene is of great relevance in that it integrates genetic and epidemiological data in the context of environmental exposures. Among the different epigenetic factors, mention must be made of DNA methylation, covalent histone modifications, and other mechanisms that include different protein complexes and RNA-mediated modifications. The regulatory effect of these phenomena upon immune response has important implications for allergic diseases. At present, different lines of pharmacological research are being conducted, based on the modulation of epigenetic factors, modifying expression of the genes that encode for proteins implicated in allergic processes. Among such modulators, mention can be made of antisense oligonucleotides, ribozymes and interference RNA. The applications of epigenetics to the diagnosis and treatment of allergic disorders offer a very promising future of this specialty.

Interactions between genes and the environment. Epigenetics in allergy / Interacciones genes-ambiente. Epigenética en alergia

Epigenetics is defined as those inheritable changes occurring in gene expression, without actual modification in the genic DNA sequence. Epigenetic factors are chemically stable, potentially reversible, and can be modulated or induced by environmental factors. In the case of allergic disease, epigenetics could explain not only the discordances observed between monozygous twins but also phenomena such as incomplete penetrance, variable expression, gender and progenitor effects, and sporadic cases. In this sense, the hypothesis of hygiene is of great relevance in that it integrates genetic and epidemiological data in the context of environmental exposures. Among the different epigenetic factors, mention must be made of DNA methylation, covalent histone modifications, and other mechanisms that include different protein complexes and RNA-mediated modifications. The regulatory effect of these phenomena upon immune response has important implications for allergic diseases. At present, different lines of pharmacological research are being conducted, based on the modulation of epigenetic factors, modifying expression of the genes that encode for proteins implicated in allergic processes. Among such modulators, mention can be made of antisense oligonucleotides, ribozymes and interference RNA. The applications of epigenetics to the diagnosis and treatment of allergic disorders offer a very promising future of this specialty

La Epigenética se define como aquellos cambios heredables que se producen en la expresión génica sin modificar la secuencia de DNA. Los factores epigenéticos se caracterizan por ser químicamente estables, potencialmente reversibles y modulables o inducibles por factores ambientales. En el caso de las enfermedades alérgicas la epigenética podría contribuir a explicar no sólo las discordancias observadas en los gemelos monocigóticos, sino también fenómenos como la penetrancia incompleta, la expresión variable, los efectos del sexo y del progenitor de origen y los casos esporádicos. En este sentido, la hipótesis de la higiene cobra gran relevancia al integrar datos genéticos y epidemiológicos en el marco de las exposiciones ambientales. Entre los factores epigenéticos destacan la metilación del DNA, las modificaciones covalentes de las histonas y otros mecanismos que incluyen distintos complejos proteicos y las modificaciones mediadas por RNA. El efecto regulador de estos fenómenos sobre la respuesta inmune tiene grandes implicaciones en las enfermedades alérgicas. En la actualidad se están desarrollando distintas líneas de investigación farmacológica basadas en la modulación de los factores epigenéticos, modificando la expresión de los genes que codifican proteínas implicadas en los procesos alérgicos. Entre estos moduladores destacan los oligonucleótidos antisentido, las ribozimas y los RNA de interferencia. Las aplicaciones de la epigenética al diagnóstico y tratamiento de las enfermedades alérgicas abre un campo muy esperanzador en el futuro de esta especialidad

Interacciones genes-ambiente. Epigenética en alergia / No disponible

La epigenética se define como aquellos cambios heredables que se producen en la expresión génica sin modificar la secuencia de DNA. Los factores epigenéticos se caracterizan por ser químicamente estables, potencialmente reversibles y modulables o inducibles por factores ambientales. En el caso de las enfermedades alérgicas la epigenética podría contribuir a explicar, no sólo las discordancias observadas en los gemelos monocigóticos sino también fenómenos como la penetrancia incompleta, la expresión variable, los efectos del sexo y del progenitor de origen y los casos esporádicos. En este sentido, la hipótesis de la higiene cobra gran relevancia al integrar datos genéticos y epidemiológicos en el marco de las exposiciones ambientales. Entre los factores epigenéticos destacan la metilación del DNA, las modificaciones covalentes de las histonas y otros mecanismos que incluyen distintos complejos proteicos y las modificaciones mediadas por RNA. El efecto regulador de estos fenómenos sobre la respuesta inmune tiene grandes implicaciones en las enfermedades alérgicas. En la actualidad se están desarrollando distintas líneas de investigación farmacológica basadas en la modulación de los factores epigenéticos, modificando la expresión de los genes que codifican proteínas implicadas en los procesos alérgicos. Entre estos moduladores destacan los oligonucleótidos antisentido, las ribozimas y los RNA de interferencia. Las aplicaciones de la epigenética al diagnóstico y tratamiento de las enfermedades alérgicas abre un campo muy esperanzador en el futuro de esta especialidad (AU)

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Alimentos transgénicos y alergia / Transgenic foods and allergy

La biotecnología consiste en la aplicación de técnicas de biología molecular y/o DNA recombinante, o la transferencia in vitro de genes (bioingeniería), para el desarrollo de nuevos productos o para dotar de nuevas características a organismos ya existentes. A pesar de los beneficios potenciales que entrañan esos métodos, han surgido elementos de preocupación tanto en lo que respecta a su repercusión para la salud como para el medio ambiente. Desde un punto de vista alergológico, esos riesgos potenciales incluyen tanto la adicción de alérgenos conocidos a alimentos previamente no alergénicos, como la formación de nuevos alérgenos y la consiguiente posibilidad de sensibilización en la población expuesta susceptible. En el conocido como Protocolo de Cartagena sobre Bioseguridad se establecieron los criterios de evaluación de los riesgos que suponen los organismos modificados genéticamente. Por otra parte, la Organización de las Naciones Unidas para la Alimentación y la Agricultura (FAO), de forma conjunta con la Organización Mundial de la Salud (OMS), han advertido también desde un punto de vista científico sobre la necesidad de evaluar la seguridad de los alimentos derivados de animales o plantas modificados genéticamente. En la presente revisión hemos querido hacer un repaso de los métodos utilizados para evaluar los potenciales riesgos de alergenicidad de los alimentos modificados genéticamente, así como de la actual legislación europea a este respecto

Biotecnology is the application of the techniques of molecular biology and/or recombinant DNA technology, or in vitro gene transfer (bioengineering), to develop products or impart specific capabilities to organisms. Despite potential benefits of such techniques, concerns have been raised about the potential consequences on health or environment. From an allergic stanpoint, potential risks include the transfer of a known allergen from a crop into a non- allergenic crop, and the creation of neo-allergens that leads the appearance of the novo sensitizaions in the allergic population. In the Cartagena Protocol on Biosafety standards for risks assessment of genetically modified organisms have been set. On the other hand, the Food and Agriculture Organization of the United Nations (FAO) joined to the World Health Organization (WHO) have provided scientific advice on the safety assessment of foods derived from genetically modified animals or plants. This review presents an overview of the methods used for the assessment of the potential allergenic risk of genetically modified foods and the current European legislation on this issue

La rinitis a la luz de los consensos internacionales / Rhinitis in the light of international consensuses

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Urticaria crónica y Helicobacter pylori / Chronic urticaria and Helicobacter pylori

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Reacciones de hipersensibilidad a fármacos quimioterápicos / No disponible

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Pollen calendar of the city of Salamanca (Spain). Aeropalynological analysis for 1981-1982 and 1991-1992.

We report a study on the contents of airborne pollen in the city of Salamanca (Spain) aimed at establishing a pollen calendar for the city for the yearly periods of maximum concentrations, relating these with quantifiable atmospheric variables over two two-year periods with an interval of 10 years between them: 1981-82 and 1991-92. The pollen was captured with Burkard spore-traps, based on Hirst's volumetric method. Determinations were made daily and were used to make preparations, previously stained with basic fuscin, for study under light microscopy at x 1,000 magnification. 946 preparations were analyzed, corresponding to the same number of days distributed over 150 weeks of the periods studied. The results afforded the identification of 48 different types of pollen grain: Grasses (Poaceae), Olea europea (olive), Quercus rotundifolia (Holm-oak), other Quercus spp. (Q. pyrenaica, Q. suber, Q. faginea, etc.), Cupressaceae (Cupressus sempervivens, C. arizonica, Juniperus communis etc.), Plantago (Plantago lanceolata, Plantago media, etc.), Pinaceae (Pinus communis, Abies alba, etc.), Rumex sp. (osier), Urtica dioica (nettle), Parietaria (Parietaria officinalis, P. judaica), Chenopodio-Amaranthaceae (Chenopodium sp., Amaranthus sp., Salsola kali, etc.), Artemisia vulgaris (Artemisia), other Compositae (Taraxacum officinalis, Hellianthus sp. etc.), Castanea sativa (Chestnut), Ligustrum sp. (privet), Betula sp. (birch), Alnus sp. (common alder), Fraxinus sp (ash), Populus sp. (poplar), Salix sp. (willow), Ulmus sp. (elm), Platanus sp. (plantain, plane), Carex sp. (sweet flag), Erica sp. (common heather), Leguminosae or Fabaceae:--Papillionaceae (Medicago sp.; Cercis sp., Robina sp.)--Cesalpinoideae Acacia sp. (Acacia),--Mimosoideae: Sophora japonica, Umbelliferae (Foeniculum sp., Cirsium sp., etc.), Centaurea sp., Cistus sp. (rock rose), Typha sp (bulrush), Mirtaceae (Myrtus communis), Juglans regia (Walnut), Galium verum, Filipendula sp. (spirea/drop wort), Rosaceae (Pyrus sp., Prunus sp., etc.), Tilia sp. (Linden), Morus sp. (mulberry), Taxus baccata (yew), Papaveraceae (Papaver rhoeas etc.), Labiata (Lavandula sp.), Cannabaceae (Humulus sp. etc.), Liliaceae (Lilium sp.), Echium sp. (viper's bugloss). The most abundant taxa, detected in the highest quantities (grains/m3 air), by order of counting were as follows: holm-oak, olive, grasses, Plantago and Parietaria. With the data obtained we have established a pollen calendar for Salamanca and report the period in which each type of pollen is found along the years and the periods with the highest airborne concentrations of such pollens. The diversity and the spectrum of the pollen in the city of Salamanca correspond to the typical plant communities found on the dehesas (large ranges of grasslands) of Castile, where Salamanca is located, although the wind directions and the peculiar climatic characteristics of the area govern the peaks of maximum presence of the different taxa. As examples, in the case of olive, which is cultivated at some distance from the city, its maximum presence coincides with south-westerly winds; in the case of grasses, the peaks of maximum counts coincide with a sharp rise in mean temperature, close to or higher than 20 degrees C and between five and six weeks after rainfall equal to or greater than 5 L/m2.