The pH of secretions in sinusitis and otitis media.

Impaired mucociliary function is a common finding in patients with recurrent respiratory infections, sinusitis and otitis media. One main component of mucociliary transport, ciliary beating activity, is sensitive to environmental hydrogen ion concentration (pH). The pH of secretion in 103 specimens from acute or chronic sinusitis and in 98 specimens from acute or secretory otitis media were measured. There were no differences between acute and chronic sinusitis (mean of pH 7.5 +/- 0.5 and 7.4 +/- 0.6) or between mucous and purulent secretions. In acute otitis media, secretion was significantly more acidic than in secretory otitis media (mean of pH 7.7 +/- 0.5 versus 8.2 +/- 0.4). The pH was less than 7.0 in 16 (15.5%) patients with chronic sinusitis and in two (8%) patients with acute otitis. The study shows that pH of sinusal or tympanal secretion is, in the majority of patients, within limits that do not cause ciliostasis.