What's new in pediatric allergology in 2005? Part 3. Respiratory allergy: pathophysiology, diagnosis, prevention and treatment (A review of the international literature from October 2004 to October 2005)

Allergic inflammation is correlated with the severity of ocular, nasal and bronchial symptoms. This inflammation results from the production of pro-inflammatory cytokines (interleukin-5, interferon-gamma, etc.) and from a deficient production of anti-inflammatory cytokines (interleukin-10, CC16, etc.), and develops very early during the course of allergic illnesses. A very early infection with respiratory syncytial virus is responsible for a Th2 response during reinfections, and may promote the development of asthma. In contrast, late infections are responsible for Thl immune responses at the time of reinfections, and may reduce the asthmatic risk. The majority of serum specific IgE determinations are useless for prediction of the atopic and asthmatic risks in young children. Those risks can be determined by interview of the parents, clinical examination, functional respiratory tests and/or determination of nitric oxide in exhaled air. Interview of the parents and clinical examination at school have good positive and negative predictive values. Except for the prescription of inhalers, other preventive measures at school and home have not a long-term efficacy. Moderate to high doses of inhaled corticosteroids have an impact on the hypothalamo-pituitary-adrenocortical axis and long-term effects on bone metabolism. The leukotriene receptor antagonist, montelukast, reduces significantly allergic inflammation, bronchial hyperreactivity and asthma symptoms in children with mild to moderate asthma. However, inhaled corticosteroids are more effective than montelukast in children with moderate to severe asthma. Finally, sublingual immunotherapy is well-tolerated by children, including children below the age of 5 years. However, the efficacy and immunologic effects of sublingual immunotherapy are still controversial. (c) 2006 Elsevier Masson SAS. Tons droits reserves.