PROBIOTICS IN PREVENTION AND TREATMENT

OF ALLERGIC RHINOCONJUNCTIVITIS AND BRONCHIAL ASTHMA

The role of probiotics has also been investigated in the prevention and treatment of allergic rhinoconjunctivitis and allergic bronchial asthma.

Allergic rhinoconjunctivitis is an inflammatory process [1] thorium of the nasal mucosa due to a reaction of the immune system triggered by inhaled allergens, towards which the patient is specifically sen [1]. This disease is one of the most common chronic conditions in children and its prevalence has increased significantly over the past thirty years.

It is characterized clinically [1] by both nasal symptoms such as congestion, sneezing [1], itching and rhinorrhea, and by general symptoms such as asthenia, malaise. Other often associated symptoms are represented by: tos [1] se, halitosis, sore throat, snoring, which negatively affect the quality of life.

Allergic bronchial asthma is a chronic inflammatory disease of the respiratory system triggered by the presence of allergens. Symptoms result from narrowing of the airways (bronchospasm) and overproduction of mucus, resulting in coughing and difficulty in breathing.

The two pathologies are strictly interconnected: allergic rhinitis is often associated with non-specific bronchial hyperreactivity, antechamber of the 'asthma. Furthermore, in the asthmatic the coexistence of allergic rhinitis tends to worsen the perception of asthmatic symptoms.

The rationale for using probiotics in this area is linked to the fact that commensal ("good") bacteria intervene in modulating the correct balance between the four main subtypes of CD4 lymphocyte cells. These cells are involved in the production of anti-inflammatory interleukins, which play a central role in respiratory allergies. Furthermore, the administration of probiotics can interfere by regulating some parameters indicative of active respiratory disease, such as the concentration in the blood of eosinophilic granulocytes.

Most of the studies conducted concerned allergic rhinitis.

Even in the case of this pathology, as for atopic dermatitis, it can be said that the best results have been obtained for the treatment of the disease already underway, compared to prevention.

The beneficial effects of probiotics in seasonal and perennial allergic rhinitis have been highlighted, both on symptoms and on the reduction of the consumption of drugs necessary for the control of the disease, as well as on the quality of life. The effect of some specific strains, such as in particular a type of Lactobacillus , the paracasei 33 , has been evaluated on allergic subjects in several controlled studies, always with positive results.

On the left a healthy bronchus on the right as it appears due to asthma

Studies conducted on breastfed infants supplemented with probiotics have shown a reduced risk of developing allergic rhinitis later in life.

In particular, a study examined 316 normal weight infants, children of allergic parents, breastfed for 4 to 6 months. One group (115) was given 5 drops of probiotic ( Lactobacillus reuteri ) every day, from the fourth to the twelfth week of life. The drops were directly applied to the mother's nipple, so that oral intake was guaranteed.

The control group instead received only breastfeeding without probiotic supplementation.

The children were followed up through the ninth year of life. During this follow-up period 19.6% of them had developed allergic rhinitis or allergic rhinoconjunctivitis, confirmed by elevated IgE values ​​and a positive Prick test.

Children in the group who received probiotics were three times less likely to develop allergic rhinitis than other children in the control group.

Indeed, adding probiotics to a child's diet has been shown to modulate the composition of the microbiota. These interventions are important for the maturation of the infantile immune system and for the development of tolerance towards various foreign substances (allergens).

The immune response in the intestine can also modulate immune responses even in distant organs, such as the nose.

Other studies have shown the benefits of probiotics also in adults with allergic rhinitis.

In this case, the probiotics administered were Bifidobacterium longum and Lactobacillus plantarum.

Adults with a confirmed diagnosis of chronic allergic rhinitis for at least two years who had taken probiotics showed a reduction in specific IgE levels directed towards dust mites compared to the control group that had not taken the probiotics.

In particular - among those who had taken probiotics - there was also a significant reduction in nasal symptoms.

Taking the right combination of probiotics can be useful for restoring balance even in the immune system of asthmatics.

The intake of Lactobacilli and Bifidobacteria would help to inhibit the proliferation of some pathogens and, in this way, would reduce inflammation and restore the balance in the immune system of the people with allergic asthma. The researchers who completed the research explained that the two particular types of probiotics have beneficial immunomodulatory properties, which increase in effectiveness when the two strains of probiotics are used in the same formulation.

Further studies will now be needed to be able to more accurately assess the clinical impact of the two types of probiotics on subjects with allergic asthma. The aim is to develop a real biotherapy for the treatment of asthma symptoms.

Dr. Rossana Cannas