Bronchopulmonary involvement in the Sjögren syndrome can lead to distal obstructive airway disease. This syndrome induces a decrease in secretions which become rare and thick, and consequently a slowing down of mucociliary activity. This activity, which can be estimated by tracheobronchial clearance studies, was investigated in seven non-smoking women (mean age = 56.7 yr) with the Sjögren syndrome but without patent distal bronchial impairment. After oral inhalation of radioactive particles labelled with 111In during spontaneous breathing (MMAD = 3 micrograms; sigma g = 1.4; energies gamma 173 and 247 keV, radioactive half-life = 2.8 days), the incorporated radioactivity was measured by a gamma-camera at the end of inhalation and then every 5 min throughout 90 min and 2, 4, 5, 6 and 24h thereafter. Biological decrease in radioactivity was exponential in form. Considering, as may authors do, the clearance of the tracheobronchial compartment to be completed within 24h, we calculated an initial biological period corresponding to the beginning of this clearance. It was equal to 101 +/- 27 min in 12 normal subjects. It was normal in three of our patients (T = 90, 91 and 101 min) and longer for the four others (T = 178, 203, 240 and 304 min). We hypothesize that three of these four patients with slow clearance and normal penetration index (tracheobronchial deposition/pulmonary deposition) had bronchiolar involvement, creating anomalies in the mucociliary escalator which were undetectable by clinical, radiological or functional examinations. These results argue in favour of strict pulmonary surveillance in patients with altered short-term clearances to enable early detection of bronchiolar disease.