We have evaluated the majority of patients might have the subjective symptom of dry nose. The nasal Schirmer test, that we have developed at the first time in Japan, demonstrated the exsistence of the dry nose syndrome with normal nasal secretion. Surface bacterial flora between normal and dry nose showed different pattern. After nasal provocation of hypertonic saline, that might cause dry eye syndrome, elevation of nasal transepithelial water loss, decrease of nasal potential differences and increase of nasal H2O2 in nasal exhaled breath condensate.
Through this study, we speculated that dry nose might be upstream of various disorders of upper airway.