Allergic rhinitis is a common disease in childhood, but nasal cytology
is rarely used by pediatricians. We compared two techniques of cell s
ampling, brushing and blowing the nose, among 77 children suffering fr
om chronic rhinitis, of whom 59 were allergic. Staining by the May-Gru
nwald-Giemsa method enabled the evaluation of the density of cells and
especially differential counting of the inflammatory cells. Staining
by the Luna method was used as a control for the eosinophils. For the
eosinophil count, we found a strong correlation between the two method
s of collecting the nasal secretions (r=0.96). Because blowing the nos
e is painless and easy to perform, it is more appropriate than brushin
g in routine use for the diagnosis of allergic rhinitis in children an
d in nasal challenge with allergens.