Revised rules for classification
| For primary SS |
| In patients without any potentially associated disease, primary SS may be defined as follows: |
| a. The presence of any 4 of the 6 items is indicative of primary SS, as long as either item IV (Histopathology) or VI (Serology) is positive |
| b. The presence of any 3 of the 4 objective criteria items (that is, items III, IV, V, VI) |
| c. The classification tree procedure represents a valid alternative method for classification, although it should be more properly used in clinical-epidemiological survey |
| For secondary SS |
| In patients with a potentially associated disease (for instance, another well defined connective tissue disease), the presence of item I or item II plus any 2 from among items III, IV, and V may be considered as indicative of secondary SS |
| Exclusion criteria: |
| Past head and neck radiation treatment |
| Hepatitis C infection |
| Acquired immunodeficiency disease (AIDS) |
| Pre-existing lymphoma |
| Sarcoidosis |
| Graft versus host disease |
| Use of anticholinergic drugs (since a time shorter than 4-fold the half life of the drug) |