Figure 1

Proposed model of the effects of PIT on disease progression in children with severe atopy. Evidence suggests that in susceptible individuals, allergic sensitisation begins early in life, even prenatally, preceding development of allergic conditions such as eczema. The number of allergens an individual is sensitised to and the number of diagnosed allergic conditions can increase with age. Inducing tolerance to an allergen using PIT early, rather than later, in life has the potential to reduce sensitisation to additional allergens and reduce the risk of progression to multiple allergic conditions particularly for children with severe atopy.