(Adnkronos) - È un mondo in costante evoluzione quello dell’Allergologia che, al netto di pratiche farlocche e approcci discutibili, consente di studiare, comprendere e gestire al meglio il capitolo complesso delle malattie allergiche. Si tratta di patologie in crescita costante che attualmente nel mondo colpiscono oltre il 20% della popolazione interessando soggetti di tutte le età con disturbi di vario genere che sembrano muoversi in rapporto con le diverse fasi della vita. Come dire che, nel corso della vita quel che cambia non è la malattia ma la forma con cui manifesta. È su queste basi che si fonda il concetto di 'marcia allergica' o 'marcia atopica', sviluppato proprio per descrivere la progressione delle manifestazioni cliniche dell’allergia, dalla dermatite atopica nei neonati, alla rinite e all'asma nei bambini e negli adolescenti. E’ questo il tema della nuova puntata di Igea, la Medicina dal mito all’intelligenza artificiale, la videorubrica curata dall’immunologo Mauro Minelli che raccoglie aggiornamenti medici ed approfondimenti relativi ai temi della salute L'atopia (dal greco ἀτοπία, cioè "fuori posto") consiste in una predisposizione genetica a sviluppare reazioni allergiche. È, dunque, la tendenza, spesso familiare, a produrre anticorpi detti 'IgE' in risposta a basse dosi di antigeni (allergeni) e, di conseguenza, a sviluppare tipiche manifestazioni cliniche come l’asma, la rinocongiuntivite, l’orticaria, la dermatite. Accade così che, seguendo la classica progressione della marcia allergica, i piccoli pazienti atopici possano andare incontro, negli anni della loro crescita, ad una sequenza tipica rappresentata da dermatite atopica, rinite e asma a determinate età, passando anche attraverso una fase intermedia, più o meno lunga, nella quale a prevalere possono essere i disturbi intestinali. Ma se la natura e lo sviluppo della malattia allergica possono variare da individuo a individuo, il legame che collega la dermatite atopica del neonato all’asma dell’adolescente è solo casuale, o ci sono dei meccanismi specifici grazie ai quali l'eczema può trasformarsi in disturbi respiratori a insorgenza più tardiva? E, se questi meccanismi esistono, quali sono e come si attivano? .
Category
🗞
NewsTranscript
00:00In the western world, about half of the children who in the early childhood have shown an atopic dermatitis will go to asthma and about a third will develop food allergies.
00:28This is why the child's eczema, even though it is generally intended to regress, can still represent for parents an important warning signal for the development of future allergies.
00:39The description of the natural progression of allergic manifestations from childhood to adulthood is emblazoned in the binomial Allergic March, which synthetically summarizes the ways in which, in allergic patients, the clinical manifestations of the disease tend to progress.
00:58It often happens to hear that atopic dermatitis is a disease that then passes with the so-called age of development. True, atopic dermatitis can pass, but often to leave room for the next step in the so-called allergic march, which is classically characterized by the appearance of food allergies with possible intestinal disorders,
01:24which in the years to come will leave room for respiratory symptoms such as rhinitis, oculoplasticity or asthma.
01:33At the same time, there is a progressive deviation of IgE, that is, of the antibodies responsible for allergies, from IgE oriented against food allergens to IgE oriented against inhalant antigens, such as acaria, pollen, fungi, rather than animal epithelium.
01:57Therefore, the Allergic March is nothing more than the synthetic but effective description of the natural history of allergic diseases, which, being able to manifest from early childhood, seem to move in relation to the different phases of life.
02:12As if to say that in allergic people, what changes in the course of life is not the disease, but the way in which it manifests.
02:21The process of developing allergies over the years is often a predictable model with early signs.
02:29For example, let's refer to atopic dermatitis.
02:35The child with atopic dermatitis is generally born with a tendentiously dry skin.
02:41Now we know that the skin is one of the main, most extensive barriers that protects the body, preventing harmful substances from the outside, perhaps infectious agents, from entering the body itself.
02:57But in the child with atopic dermatitis, the skin has scabs, it is rather dry and still with major lesions.
03:09This, of course, in addition to exposing the child to an increased risk of infections,
03:14obviously makes it possible to penetrate the deepest layers of the skin with allergenic substances that the child can touch or with which the child can come into contact.
03:26These allergenic substances, evidently passing through an abrasive skin, come into direct contact with immune-competent cells, sensitizing them,
03:37thus making them capable of causing allergic reactions, increasingly severe, to each new subsequent contact with that same sensitizing agent.
03:48Behind this scenario, there is evidently a kind of genetic predisposition, in the sense that the cells that make up the epithelium,
03:58that is, the layers of coating of our mucosa, the skin, the intestinal mucosa or the respiratory mucosa,
04:05these cells are held together by some proteins that somehow act as a glue.
04:11Among these proteins, especially filaggrin and occludin, the synthesis of these proteins is regulated by some specific genes.
04:20Now, in atopic children or in any case in atopic people, these genes can be mutated, can be altered,
04:28which will lead to a deficit of those proteins, which in turn will make the epithelium much more permeable and consequently much more vulnerable.
04:40Allergic diseases can have a negative impact on a person's quality of life.
04:45In some cases, they can put the patient's life in serious danger.
04:49In the field of food allergies, for example, the most exposed to clinically serious problems is above all the pediatric population,
04:58both because in that age group there is a greater probability of encountering foods at high risk of hidden allergens,
05:05such as snacks, ice creams or candies,
05:08and because among older children there is a higher incidence of food-causing reactions,
05:12precisely for the reasons associated with the progression of the allergic process.
05:16Hence the question, is it possible to stop the allergic process?
05:21Block its progressive evolution?
05:23Is it possible to prevent the development of asthma, food allergies or atopic dermatitis?
05:30Some measures could, in this sense, be protective.
05:34Various experiments, for example, would suggest that the early introduction of solid foods in young children
05:41can effectively prevent the emergence of food allergies.
05:45Avoiding cigarette smoke or exposure to pollutants outdoors or indoors,
05:52such as dust or flies, can certainly help reduce the risk of asthma or other respiratory conditions.
05:59For my part, I would like to underline, since early childhood,
06:04the great importance of impermeability, that is, the correct composition of the intestinal barrier,
06:12which will become very important to avoid the emergence of allergies even in adulthood.
06:22www.microsoft.com
06:24www.microsoft.com
06:26www.microsoft.com
06:28www.microsoft.com
06:30www.microsoft.com