bronchial asthma / Bronchial asthma Introduction, definition and epidemiology

     Bronchial asthma Introduction, definition and epidemiology

Bronchial asthma is one of the most frequent pathologies not only of the adult but also of the child, affecting hundreds of millions of individuals around the world and unfortunately provoking, even today, hundreds of thousands of deaths confirming its danger, of frequent underestimation of the problem and the consequent inadequacy of prevention and treatment. Environmental factors are more important than the racial factors in the onset and persistence of the disease and the number of cases is everywhere increasing in both children and adults.

 Asthma consists of a reversible obstruction of the airways (bronchi), whose characteristic symptoms are represented by cough, often dry and irritating but sometimes more catarral (production of bronchial secretion), difficulty in breathing reported by the patient as a general discomfort to to breathe mainly the expiratory phase, a feeling of constriction in the chest and wheezing ("whistle") which, in the most intense phases of the asthmatic crisis, can be perceived not only by the patient but also by a person who is close to him. At the base of the multiple mechanisms that determine it and that favor the acute crisis we must consider the inflammation of the airways (often present even when the patient does not present acute crises) and the spasm of the bronchial muscles (bronchospasm), with all the consequences clinics that can derive from this dual dysfunctional moment. The asthmatic exacerbations, sometimes very serious, can also put the patient's life at risk and need to be treated at hospital emergency centers. Patients who risk situations of such severity must be carefully monitored over time and must remain under constant specialist supervision.

It should be remembered that a huge number of asthmatic patients is sensitive to multiple allergens (substances present in the environment and to which patients can sensitize themselves), justifying in this the frequency of finding patients suffering not only from bronchial asthma but also from allergic diseases not only the airway. Often the asthmatic illness gets worse during the hours of night rest or when the patient comes into contact with respiratory allergens for which it is sensitized.

bronchial asthma bronchus section

 Schematic representation of the detail of the section of a bronchus in a patient suffering from bronchial asthma: note the bronchial wall thickened by inflammation, the reduction of caliber of the secondary bronchus to the spasm of the smooth muscle and the presence of secretions within the bronchial lumen . Natural history of asthma

Bronchial asthma can occur at any age. In childhood, asthma is often associated with allergy (see also "allergic diseases of the airways" and "pollinosis") and in this age group the main allergens are represented by house dust mites. Viral infections can also be an important triggering factor, opening a clinical history of asthma in patients previously suffering from conjunctivitis or seasonal allergic rhinitis (see also "allergic rhinitis"). In 30-50% of cases, asthma may disappear at puberty but it can often reoccur into adulthood, at which time patients may develop an airway obstruction that is no longer completely reversible. Causes and favorable factors

Speaking of the causes and the factors favoring the asthmatic illness and of the relative acute crises, it is necessary to take into account numerous qualifying points, among which:

 Genetic factors and atopy: there is often an asthmatic familiarity in the families of patients with bronchial asthma, with frequent finding of asthmatics with asthmatic parents and ease of having asthmatic children. This is easier in families with the presence of atopy, a condition known as the general predisposition of the patient to manifest allergic diseases.

Nonspecific bronchial hyperreactivity (see also: "Non-specific bronchial hyperreactivity"): it is intended for non-specific bronchial hyperreactivity a particular sensitivity of the bronchi to respond with a bronchospasm (bronchial smooth muscle spasm) when exposed to generic stimuli often very different from each other ( cold air, dry air, irritating powders, pharmacological stimuli, etc.). This particular sensitivity significantly influences the clinical presentation of asthma in the patient affected by the disease




allergens pollenAllergens: means with "allergens" a large multitude of substances that can sensitize the patient beforehand and then trigger, in the same, local allergic reactions or general even serious when the patient is exposed to them. The majority of asthmatic patients are allergic to allergenic substances that support the asthmatic crisis and in this sense their identification is fundamental in order to limit as much as possible the contact of the patient with one of them, once known. Among the allergens most frequently responsible for asthmatic crises are, especially in the case of asthma in children, house dust mites, animal allergens (dog and cat), pollens (birch, hazelnut, various trees, grasses, parietaria, ambrosia, composite and others) and many food allergens. Even some microscopic fungi of environments confined or dispersed in the environment can be responsible for asthmatic crises

mite

Dermatophagoides Pteronissinus (electron microscope): house dust mite, main responsible for allergic sensitization in asthmatic children and with perennial allergic rhinitis

Respiratory infections: often the clinical history of the hormone already present a particular family predisposition to disease, begins after a viral infection of the airways (also a "simple" infection by influenza virus) and from that moment the patient, first healthy, it begins to present that state of nonspecific bronchial hyperreactivity that will often maintain over time and will form the basis of asthmatic disease. Any infection of the airways, then, supported by viruses or bacteria, can complicate the clinical picture of patients suffering from asthmatic disease and can lead to sometimes very serious clinical situations that can proceed to a real condition of respiratory failure.

Low birth weight: low birth weight may be a factor favoring the subsequent development of bronchial asthma.

Air pollution (smog): is perhaps the most common cause responsible for the increase in asthma cases in recent years, both as a result of a direct irritation mechanism of the airways by inhalation pollutants dispersed in the environment, and for the significant numerical increase in cases of allergic respiratory diseases and, consequently, of cases of asthma related to them.

Cigarette smoke: it is the most common cause in the domestic environment, representing a real risk factor for the development and maintenance of asthma in children.

Food additives: the sulphites present in particular in white wines are often the cause of asthmatic crises.

Irritating substances in working environments: among these the isocyanates of the painting departments represent one of the inhalants most frequently associated with the development of bronchial asthma.

Gastroesophageal reflux: gastro-oesophageal reflux disease with the ascent of acid gastric juice into the esophagus and sometimes to the mouth can cause asthmatic crises especially during nighttime rest.

Stress: some conditions of strong emotional and physical stress can trigger asthma and sometimes very serious crises.

Cold: the asthmatic patient exposed to low temperatures or forced to inhale cold air may experience bronchospasm.

Particular situations: it can sometimes happen that the asthmatic patient goes through an acute crisis even during prolonged laughter, during singing or during crying.
Diagnosis

Diagnosis of bronchial asthma is made possible through:

1) Adequate medical history. What the patient reports in relation to the perceived respiratory discomfort (symptoms), together with a series of targeted questions posed by the specialist pulmonologist, serve to correctly guide the diagnosis of asthma and to identify the most probable causes of the respiratory crisis when the same rises. This results, over time, essential for the prevention of asthmatic crises and consequently for a more effective management not only of the pharmacological therapy but also of the many extra-pharmacological aspects that a good control of the disease imposes.

2) Medical examination. It allows to detect the characteristic auscultatory picture of bronchial obstruction (bronchospasm).

3) Spirometry examination (spirometry): consists of a very simple functional examination, able to be well accepted even by children who, if properly conducted, allows to determine respiratory parameters important for the diagnosis and subsequent control of the results of the therapy.
















    Allergic tests: they consist in a complete investigation of the possible sensitizations of the patient to allergens of the environment, that from the simplest and quick skin tests with specific allergens reach up to the research of specific antibodies for respiratory and alimentary allergens through blood sampling

. 5) Test with methacholine. Useful to the pulmonologist specialist for those doubtful cases in which, being unable to visit the patient in a moment of overwhelming asthmatic crisis, there is a doubt concerning the true nature of the respiratory discomfort that the patient reports. The test allows to detect the non-specific bronchial hyperreactivity, definable as that particular condition of bronchial predisposition to undergo bronchospasm if exposed to non-specific stimuli (generic irritants).

 6) Chest radiography. Useful to identify particular conditions sometimes correlated with the onset of crises.

 7) Gastroscopy. Although apparently not justified for the identification of the causes of asthmatic disease (clinical diagnosis already reported), it is instead important in particular and selected cases for the identification and confirmation of gastro-oesophageal reflux disease (GERD), often at the basis of important asthmatic crises of adults and children. Treatment

Asthma does not heal (30-50% of children, however, experience adulthood remission in adulthood), but can be controlled. Treatment programs include patient education and periodic assessment of disease intensity. Drug treatment should be adjusted to the severity of symptoms to achieve maximum therapeutic effect with the least amount of drugs. It is essential to know that asthma arises and is kept under control by suppressing the inflammation of the airways and not only treating bronchospasm. The lack of respect for this point, often caused by the patient's poor acceptance of therapy for underestimating the problem or for unjustified fear of therapy, is the basis of therapeutic failures and the persistence of still excessive mortality, especially considering the goodness of the drugs available today.

 The goals of asthma treatment include:
   Minimize disease symptoms  
Maintain respiratory function as close to normal as possible, preventing the development of asthma in bronchial obstruction no longer reversible and mortality  
Abolish or at least reduce asthmatic exacerbations
    Minimize the need to resort to "needy" drugs
  Prevent emergencies and hospitalizations
   Allow the patient to perform any physical and sporting activity
   Reduce and minimize
 the side effects of antiasthmatic drugs Patient education Effective asthma control involves the knowledge of many relevant aspects that go beyond the simple administration of drugs and which can not be ignored if the maximum result is achieved with the less use of the drugs themselves. Between these:
    Control of the external environment and the domestic environment (pollen filters, allergens, house dust and proper management of mites, animal fororms and contact with animals especially with children, adequate control of the humidity of the house, furniture and furnishings , toys, vacuum cleaners and dedicated filters, correct air changes in the house taking into account the pollination periods of the plants during the year, etc.).     Choice of place and holiday periods

   Ventilation and adequate air conditioning of the house and vehicles  
Knowledge of pollen calendars 

 Proper management of rain-sun cycles during pollination periods

   Proper management of body weight 

 Outdoor and indoor sports activities  

Careful evaluation of the choice of sports activities to be practiced and management of the same under specialist medical supervision 

 Active tobacco smoke and passive exposure 

 Work activity and exposure to occupational pollutants (isocyanates, etc.)  

Food allergies and food and drink preservatives (sulphites, etc.)

  Pharmacological allergies (asthma aspirin and salicylates, etc.)

   Intestinal infections and exposure to allergens in patients with atopy

   Knowledge of cross reactivity between food allergens and pollen

     Gastro-esophageal reflux disease (GORD) control







Correct management of the psychological aspects of the disease and of the emotional states both in the patient and in the parents of the young asthmatics
    Control of patient adhesion to therapy and correct administration of inhaled drugs
    Evaluation of the statural growth curves in the treated child
    Adequate activation of therapy in the pre-seasonal period compared to the appearance of allergenic pollens in the environment

Drug therapy

cans for asthma There are two different pharmacological strategies to treat asthma: a direct control of the disease aimed at avoiding the appearance of respiratory crises; the other used to solve acute respiratory crises urgently when they arise. It is obvious that the effectiveness of the control therapy and the application of the various points mentioned above will be all the better, the less we must resort to resolving acute crises, with all the serious risks involved. Without going into technical details of relevance more than the specialist pulmonologist than the asthmatic patient, it is useful to know that you can count on numerous drugs having action points sometimes very distant from each other but that, if well used, allow you to obtain the desired result . It goes therefore from inhalation drugs to rapid and slow bronchodilator action, to inhalation and general cortisones, to drugs for the control of allergy and to those useful to make cells that release substances that trigger the crisis less reactive. What must be very clear, however, is that there is no "therapy" of asthma, but instead there is the therapy of "that that", thus indicating the need for a rigorous personalization of the therapeutic program traced on each individual patient.
Prevention

Diets low in food allergens and feeding the baby with breast milk have shown positive effects only in the first years of life. The growth with dogs and cats from the first months of life can be a protective factor towards the onset of allergic sensitization to these animals, but when the sensitization has already developed contact with dogs and cats is a risk factor for the aggravation of asthma.

The prevention of obesity in children and the control of body weight are important for all ages, as overweight asthmatics tend to control asthma in a much more difficult way and to present more serious asthma exacerbations during the year.

Allergic rhinitis (see also "allergic rhinitis") represents a very important risk factor for the subsequent evolution of the same in bronchial asthma and often an adequate and early initiation of therapy with anti-pollen vaccines (specific hyposensitization therapy) can prevent this complication . When these diseases coexist a combined therapy of the two is necessary, as allowing proper nasal breathing also helps to reduce the asthmatic respiratory discomfort.
HYPOALLERGENIC DIET IN PREGNANCY AND LACTATION TO REDUCE THE RISK OF ALLERGIC SENSITIZATION OF THE BIRTHDAY / NEWBORN

ASMA - HYPOALLERGENIC DIET IN PREGNANCY AND BREASTFEEDING FOR REDUCING THE ALLERGIC RISK OF SENSITIZATION OF THE BIRTHDAY-BABY
Download the table as a pdf

I still like to remember how the asthmatic illness is first of all a disease of the "person" and not simply a disease of the "bronchi" and, as such, is also negatively affected by a series of psychological implications and that poorly controlled emotional states patient's interior that, if not properly taken into account and not properly addressed and resolved, will hardly allow the desired and expected therapeutic result.