Salivary gland parameters and clinical data related to the underlying disorder in patients with persisting xerostomia

Abstract
This study assessed salivary gland parameters and clinical data in patients referred to our clinic because of persisting xerostomia of unknown origin, in order to facilitate early diagnosis and recognition of the underlying disorder. Most patients were referred for diagnostic analysis of a possible Sjögren's syndrome (SS). A complete diagnostic work-up was available in all patients (n = 176), including data on salivary gland function, saliva composition, sialography, salivary gland swelling, pattern of complaints, general health, and medication. Patients were diagnosed with SS (n = 62), sialosis (n = 45), sodium retention syndrome (n = 30), or medication-induced xerostomia (n = 9). In 30 patients no disease related to salivary gland pathology was found. Unstimulated whole salivary flow was decreased in all patients, except in patients with sodium retention syndrome and in patients without salivary gland pathology. Submandibular/sublingual salivary flow was lowest in SS patients. SS and sialosis patients had increased salivary potassium concentrations, whereas only SS patients had increased sodium concentrations. About half of the sialosis patients mainly complained of persistent parotid gland swelling. Xerostomia-inducing medication was used by most patients. It was concluded that gland-specific sialometry and sialochemistry is useful in discriminating between the various disorders causing persisting xerostomia.