[Infection and asthma. V. Study of childhood asthma and viral infection by cytological analysis of nasal smears].

Cytological analysis of nasal smears was carried out for 295 asthmatic children aged 2 to 15 years old at the time of asthma attack and non-attack, in combination with blood tests and chest roentgenograms. Damaged ciliated cells (ciliocytophhthoria, CCP) were looked for as a marker of viral infections. The appearance rate of greater than 2+ of CCP was higher among children during attack (38/70, 54.3%) than that among children not suffering an attack (6/29, 20.7%); this was pronounced among young children under five. However, the results of blood examinations and chest roentgenograms did not correlate with the rate of positive signs of infections in CCP positive- or negative-attack. These results suggest that the cytological examination of nasal smears in useful in evaluating the presence of viral infections during asthma aggravation among young children, whereas evaluation of these infections may be difficult by blood tests or chest roentgenograms.