We determined the tracheo-bronchial mucociliary clearance (MCC) in order to evaluate a possible impairment of this function in patients affected by Sjögren's syndrome (SS) with or without overt clinical symptoms of xerotrachea. The MCC was expressed as flow rate (mm/min) and studied in 22 non-smoking SS patients (10 pSS and 12 sSS) and in 8 control subjects by specifically adapted ventilation lung scintigraphy (VLS). The MCC in the control group was 5.9 +/- 1.1 mm/min. No values were produced for MCC in 16 SS patients (8 pSS and 8 sSS) in the time interval considered and were reduced in the remaining 6 SS patients (3.3 +/- 1.2 mm/min). In all nine cases with clinical evidence of xerotrachea no values for MCC were obtained. A significant correlation was found between the MCC values and the rate of stimulated salivary excretion determined by dynamic scialoscintigraphy in the same patients (p < 0.001). These preliminary data show that the majority of SS patients studied presented with MCC impairment, always found when clinical symptoms of xerotrachea were present.