Air pollution and allergens

It is well known that the prevalence of allergic diseases has increased in recent decades in the industrialized world. Exposure to environmental pollutants may partially account for this increased prevalence. In effect, air pollution is a growing public health problem. In Europe, the main source of air pollution due to particles in suspension is represented by motor vehicles--particularly those that use diesel fuel. Diesel exhaust particles (DEPs) are composed of a carbon core upon which high-molecular weight organic chemical components and heavy metals deposit. Over 80% of all DEPs are in the ultrafine particle range (< 0.1 pm in diameter). Air pollutants not only have a direct or indirect effect upon the individual, but also exert important actions upon aeroallergens. Pollen in heavily polluted zones can express a larger amount of proteins described as being allergenic. Through physical contact with the pollen particles, DEPs can disrupt the former, leading to the release of paucimicronic particles and transporting them by air--thus facilitating their penetration of the human airways. Climate change in part gives rise to variations in the temperature pattern characterizing the different seasons of the year. Thus, plants may vary their pollination calendar, advancing and prolonging their pollination period. In addition, in the presence of high CO2 concentrations and temperatures, plants increase their pollen output. Climate change may also lead to the extinction of species, and to the consolidation of non-native species--with the subsequent risk of allergic sensitization among the exposed human population. In conclusion, there is sufficient scientific evidence on the effect of air pollution upon allergens, increasing exposure to the latter, their concentration and/or biological allergenic activity

Use of antihistamines in pediatrics

Drugs with antihistamine action are among the most commonly prescribed medicines in pediatrics. According to the International Medical Statistics (IMS), almost two million antihistamine units (in solution) for pediatric use were sold in Spain during 2006 - at a cost of nearly 6 million euros. Of this amount, 34% corresponded to first-generation (or sedating) antihistamines. The difficulties inherent to research for drug development increase considerably when the pediatric age range is involved. The use of any medication in this age group must adhere to the strictest safety criteria, and must offer the maximum guarantees of effi cacy. For this reason, detailed knowledge of the best scientific evidence available in relation to these aspects is essential for warranting drug use. The first-generation antihistamines have never been adequately studied for pediatric age groups, though they are still widely used in application to such patients. In contrast, studies in children have been made with the second-generation antihistamines, allowing us to know their safety profile, and such medicines are available at pediatric dosages that have been well documented from the pharmacological perspective. The present review affords an update to our most recent knowledge on antihistamine use in children, based on the best scientific evidence available

Allergic rhinitis: continuous or on demand antihistamine therapy?

Allergic rhinitis is an inflammatory disease of the nasal mucosa, caused by an IgE-mediated reaction after exposure to the allergen to which the patient is sensitized. Histamine is the most important preformed mediator released in the early stage of the allergic reaction, and also contributes to the late phase of the latter, exhibiting proinflammatory effects. Minimal persistent inflammation is a physiopathological phenomenon induced by the presence of an inflammatory cell infiltrate, together with ICAM-1 expression in the epithelial cells of the mucosa exposed to the allergen to which they are sensitized, in the absence of clinical symptoms. This molecule is considered to be an allergic inflammatory marker. The priming effect first described by Connell in 1968 consists of the reduction in the allergen concentration required to elicit a nasal hyper-response when performing a daily nasal exposure test. This implies that with natural exposure to inhaled allergens, small amounts of environmental allergen will maintain the patient symptoms, and thus of course minimal persistent inflammation. Considering the above, it is questionable whether antihistamines should be administered on a continuous basis or upon demand. The antihistamines, and fundamentally the second-generation drugs, have been shown to exert an antiinflammatory effect, and this effect is greater when the drug is administered continuously than when administered upon demand. Likewise, a reduction in treatment cost and an improvement in quality of life among patients treated on a continuous basis has been documented. However, no studies have been specifically designed to clarify the indication of treatment on a continuous basis or upon demand, as occurs in the GINA. As a result, the individualization of treatment according to the concrete characteristics of each patient seems to be the best approach, at least for the time being

Effect of pollutants upon patients with respiratory allergies

Epidemiological studies have revealed an association between pollution and allergic respiratory diseases. The main pollutants in this sense are nitric oxide, ozone, and particulate matter. The present review on one hand addresses the chemical characteristics of each of these three groups of pollutants and their main sources, and on the other examines their effects upon allergic respiratory diseases--placing special emphasis on the effects of diesel exhaust particles. For each of the pollutants, the underlying mechanisms capable of influencing allergic respiratory diseases are commented. Lastly, an evaluation is made of some of the genetic aspects related to the response to pollutants

Free nasal floor mucosal grafting after endoscopic total ethmoidectomy for severe nasal polyposis: a pilot study

[Background] We report a novel surgical technique based on an endonasal free mucosal graft (mucoplasty) for improving clinical results and local healing in chronic rhinosinusitis with nasal polyps (CRSwNP).[Methods] Patients diagnosed with bilateral CRSwNP scheduled for endoscopic sinus surgery were included. They underwent complete removal of anterior and posterior ethmoid cells, in addition to bilateral type III frontal sinusotomy. An endoscopic mucoplasty was performed in the left nasal cavity, whereas the right nasal cavity served as control. Patients were evaluated before surgery and 6 months after operation, including Sino-Nasal Outcome Test (SNOT-22), Visual Analogue Scale (VAS) for olfaction, endoscopic evaluation using the Modified und-Kennedy (MLK) scoring system and healing evaluation.[Results] Ten patients (mean age 53.6 years) were included. A significa t decrease of SNOT-22 score from 57.0 (21.1) to 20.3 (20.6) (P = 0.024) and a non-significa t decrease of VAS for olfaction score from 9.3 (0.5) to 4.6 (3.9) were found. Preoperative mean MLK score was 4.9 (0.7) in the right nostril and 4.8 (1.0) in the left one. After operation, there was a greater decrease of MLK score in the left nostril than in the right (1.9 [1.0] vs. 1.3 [0.8], P = 0.034). Better healing was proved in the nostril with the mucoplasty.[Conclusion] Endonasal mucoplasty could be an effective, safe and feasible complementary surgical procedure in the treatment of CRSwNP. The reduced local edema associated with lower amount of secretions may confer a better control in the frontal recess, orbital wall and nasal roof

Rinitis, poliposis nasal y su relación con el asma.

The aim of this review is to assist pulmonologists in the management of diseases involving both the upper and lower respiratory tract that are linked by a common, interrelated epidemiology, clinical signs and symptoms, and inflammatory mechanism - asthma, in particular. The document discusses the definitions of the various sinonasal phenotypes associated with asthma: allergic and non-allergic rhinitis and chronic rhinosinusitis with or without nasal polyps. Diagnostic criteria and severity levels are also listed. Particular attention has been given to the 2 main syndromes associated with asthma: (i)allergic rhinitis, the most common, and (ii)chronic rhinosinusitis with nasal polyps, the disease most closely associated with severe asthma. To summarize, the upper respiratory tract should always be evaluated in order to achieve a single diagnosis and comprehensive treatment of the "united airway"

Rinitis, poliposis nasal y su relación con el asma

El objetivo de esta revisión es facilitar al neumólogo el manejo de las enfermedades de la vía respiratoria superior ligadas a la vía respiratoria inferior, especialmente al asma, unidas por una epidemiología, una clínica y un mecanismo inflamatorio comunes e interrelacionados. El documento recoge las definiciones de los diferentes fenotipos nasosinusales ligados al asma: rinitis alérgica o no alérgica y rinosinusitis crónica con o sin pólipos nasales. Asimismo se recogen los criterios diagnósticos y su nivel de gravedad. Se dedica especial atención a los dos síndromes principales asociados al asma: 1) rinitis alérgica, la patología más frecuente, y 2) rinosinusitis crónica con pólipos nasales, la patología más ligada al asma grave. En síntesis, en el manejo del asma debe valorarse siempre la vía respiratoria superior con la finalidad de un diagnóstico unificado y un tratamiento integral de la vía respiratoria única