ASTHMA and ECZEMA

• Asthma is an inflammatory disease of the small airways of the lungs
• Infantile eczema (atopic dermatitis) is an inflammatory disease of the skin
• Atopic dermatitis, asthma, and hay fever (allergic rhinitis) are all considered part of a common syndrome of atopic diseases
• ‘Atopy’ refers to the presence of IgE-mediated positive skin-test responses to common allergens, such as dust mites. Moreover, these individuals also have increased levels of total IgE in the serum
• Currently, asthma is present in 60% of children with severe atopic dermatitis
• Overall, atopic diseases, such as eczema and asthma, have all increased in frequency in recent decades and now affect about 20% of the population in the developed world. Interestingly, these diseases are rare in under-developed nations
• Both diseases are known to be familial, meaning that they arise from both strong genetic and environmental factors
• Twin and family studies have shown that predisposition to atopic disease is highly heritable
• References:
• Johansson SG et al. A revised nomenclature for allergy. An EAACI position statement from the EAACI nomenclature task force. Allergy 56, 813-824 (2001).