Recurrent respiratory infections are primarily diagnosed in early childhood, although they affect many adults as well.
The newborn comes to the world with non-specific immunity, given by his mother during pregnancy. This creates the first line of protection against microorganisms; bacteria and viruses from the external environment. In newborns, infants and young children, the immune system is still “untrained” because immune antibodies haven’t had the opportunity to contact a large number of pathogens thus immune memory have not been developed. This process takes place intensely during first few years of life when a child faces increased number of infections from the respiratory system, middle ear and others. The problem arises when the process of shaping the child’s immunity is disturbed. Most cells in the immune system (70-80% of immunocompetent cells) are located in the digestive tract. The function of the immune system depends on the functioning of these cells, i.e. the better state of immunity, the quicker and more effective fight against infection.
The intestinal microflora is responsible for shaping the proper immune system reaction. Bacteria in the gut are known to be the first microorganisms serving as “trainers” of immune cells. Beneficial microbes in the intestine shape the correct immune profile, guaranteeing balance between Th1 and Th2 lymphocytes (imbalance is the cause of allergies and autoimmune diseases), stimulating the production of antibodies and consequently reducing inflammation. The influence of gut microbiota on one’s immune system is therefore dominant.
It is easy to imagine that disturbances in the composition of the intestinal microflora must result in the deterioration of the immune system function and, as a result, the development of recurrent infections. In children born via cesarean delivery and/or fed with milk formulas, microflora composition was found to be significantly impaired. Initial colonization of the intestine occurs as a result of the takeover of bacteria from the genital tract of the mother. The mother’s milk contains not only health-promoting Bifidobacterium genus bacteria, but also a bifidogenic factor (a natural prebiotic) stimulating the intestinal ecosystem growth. Children deprived of these two factors are usually much more susceptible to infections. The usage of antibiotics further elevates the intestinal microflora disruptions, impoverishing child’s immunity.
During the adulthood, a number of factors cause intestinal dysbiosis, predisposing to the development of recurrent infections. These include not only antibiotics, but also other drugs (e.g .non-steroidal anti-inflammatory drugs), stimulants, stress and a number of others. For this reason, evaluation of the intestinal microflora composition should be the first step in the prevention and treatment of recurrent infections. In turn, in case of microbiota abundance disruptions, targeted supplementation with selected probiotics and prebiotics should be administered.
The reason for the improper functioning of the immune system also includes the excessive adverse reactions to consumed food. Hypersensitivity of IgG and IgA – dependent type was discovered to improperly involve the immune system, and a reaction toward allergic foods instead of preventing the development of infection occur. As a consequence, hypersensitivity of IgG and IgA – dependent types are responsible for increased susceptibility to respiratory tract infections, middle ear and others.
In case of recurrent respiratory infections, the following tests are recommended: