CETIRIZINE REDUCES ICAM-I ON EPITHELIAL-CELLS DURING NASAL MINIMAL PERSISTENT INFLAMMATION IN ASYMPTOMATIC CHILDREN WITH MITE-ALLERGIC ASTHMA

It has been recently demonstrated that individuals who suffer from mit e allergy present mucosal inflammation even when asymptomatic. This si tuation is characterized by infiltration of inflammatory cells (eosino phils and neutrophils) and by ICAM-I expression on epithelial cells. I t has been called 'minimal persistent inflammation' (MPI) for its rela tionship with natural. exposure to allergen,which is continuous in the case of mite allery. ICAM-I (or CD54) expression on epithelial cells is relevant for several reasons: (a) healthy individuals and patients with pollen allergy out of the pollen season do not express this molec ule; (b) ICAM-I is the natural ligand of LFA-1 (an integrin expressed on granulocytes), and (c) ICAM-I is also receptor for rhinoviruses. It is well known that viral infections precede asthmatic attacks; conseq uently, this correlation is more frequent in cases of mite allergy. Ce trizine is an antiallergic drug that can reduce both inflammatory infi ltrate and ICAM-I expression induced by allergen-specific conjunctival challenge. The aim of this study was to evaluate the effect of cetiri zine on MPI in 20 children (5-14 years old) with mite allergy. All the children suffered from mild asthma and 9 also had rhinitis (they had been asymptomatic, and thus not treated, for 2 months). The study was double-blind, placebo controlled and randomized and children took Ceti rizine or placebo for 15 days. At the beginning and end of the study, nasal scrapings were performed to evaluate inflammatory cell infiltrat ion (eosinophils and neutrophils) and ICAM-I expression on epithelial cells. Cetirizine-treated children showed a significant reduction (or even total absence) of ICAM-I expression on epithelial cells (p < 0.00 2) and a reduction trend in inflammatory cell counts compared with pla cebo. In conclusion, Cetirizine might be envisaged as fruitful for the prolonged treatment of allergic children, including during clinical l atency, to prevent possible relapse or rhinovirus infections.