patients unlikely to have these autoantibodies (e.g., males, the elderly, and patients with a sicca-limited disease) are not classifiable as primary SjS using these criteria.

Patients who fulfill the 2002 criteria who have either a specific histological diagnosis (lymphocytic infiltration) or possess highly specific autoantibodies within their sera might be regarded as having Sjögren’s “disease.” It is possible that etiopathogenic mechanisms other than lymphocytic-mediated epithelial damage are involved in patients with negative minor salivary gland biopsies and negative autoantibody assays. For those patients, the term Sjögren’s “syndrome” seems more appropriate [18]. The heterogeneity in the clinical presentation of primary SjS observed in the largest series of patients [11, 12] shows that our understanding of how to diagnose this systemic autoimmune disease is still evolving.

35.4.2Diagnostic Methods

35.4.2.1Keratoconjunctivitis Sicca

The main ocular tests are Schirmer test and rose Bengal staining. The Schirmer test for the eye quantitatively measures tear formation via placement of filter paper in the lower conjunctival sac. The test result is positive when less than 5 mm of paper is wetted after 5 min. This test is simple to perform in primary care. Rose bengal scoring involves the placement of 25 mL of rose Bengal solution in the inferior fornix of each eye and having the patient blink twice. Rose bengal staining of the ocular surface is an important observation in the detection of SjS and important in differentiating the keratoconjunctivitis sicca of primary SjS from other causes of dry eye [10]. A staining score of 4 or more on the van Bijsterveld scoring system is considered to be significant [16]. Because of the irritative nature of Rose Bengal staining, lissamine green is now often used in its place.

35.4.2.2Xerostomia

Several methods to assess oral involvement have been proposed [6, 8], such as measurement of the salivary flow rate, sialochemistry, sialography or scintigraphy. Measurement of the salivary flow, with or without stimulation, is the simplest method in evaluating xerostomia. The procedure is acceptable to patients and requires no special equipment [19]. Normal unstimulated salivary flow should be greater than 1.5 mL in 15 min. Salivary gland scintigraphy using intravenous injection of 5 mCi of sodium pertechnetate (99mTc) is a functional test performed primarily in specialty centers and tertiary care hospitals.

35.4.2.3Salivary Gland Biopsy

Minor salivary gland biopsy remains a highly specific test for the diagnosis of SjS. However, it is an invasive technique that can lead to local side effects if not performed correctly. Thus, the procedure should be performed only by an individual experienced in this technique.