REVIEWS  ALLERGIC RHINITIS 

Otorinolaringologia 2006 March;56(1):17-25

Copyright © 2006 EDIZIONI MINERVA MEDICA

language: English

Probiotics as therapy for atopic disease

Furrie E.

Department of Immunology Ninewells Hospital and Medical School, Dundee, UK

Probiotics are live microbial food supplements that display a positive benefit to the health of the recipient. It is known that they improve colonisation resistance to pathogen infection in the gastrointestinal tract. It is also proposed that they have an effect on both control of immune homeostasis and strengthening of barrier function at epithelial surfaces throughout the body. Allergy is caused by an immune reaction that is out of all proportion to the antigenic stimuli. Classical allergy is a type I hypersensitivity reaction mediated by the interaction of mast cells (and eosinophils) coated with allergen specific IgE and a crosslinking allergen. The physiological outcome is inflammation commonly displayed by urticaria, rhinitis, vomiting and diarrhoea depending on the route of allergen entry. In extreme reactions anaphylactic shock can result which may lead to death. Chronic allergic responses most commonly present themselves as asthma and eczema (atopic dermatitis). All these symptoms are the consequence of an inappropriately stimulated immune system making a response to an environmental or food antigen. On bacterial colonisation of the sterile colon after birth the appropriate microbiological stimuli are essential to redress the balance of the skewed Th2 immune response present in the newborn. This normal interaction between baby and microbes is thought to be compromised in the western world with a reduction of bifidobacteria and an increase in clostridial species particularly in bottle fed infants. The use of probiotic therapy to prevent induction of allergic disease has been demonstrated in a number of studies using a probiotic E. coli and lactobacillus GG in neonates. They demonstrated a long-term reduction in dermatological symptoms of allergy in the test group with lactobacillus reducing the incidence of atopic eczema. Management of allergy through probiotics has also been demonstrated in infants using lactobacilli in controlling atopic eczema with or without cows milk allergy. Unfortunately these positive results have not been repeated in studies with older children and young adults in asthma and allergic rhinitis.