It is often difficult to diagnose Sjögren's syndrome. In fact, it may take years before a definite diagnosis is made.
A specialist in autoimmune diseases (known as a rheumatologist) is usually required to establish the diagnosis.
The diagnosis of Sjögren's syndrome is made based on the careful analysis of many factors. A thorough history and physical examination are essential. Also, there are certain laboratory studies that can be helpful when considering the diagnosis. It is important to note that a diagnosis cannot be made based on any specific blood test alone.
In 2016, the American College of Rheumatology (ACR) and European League Against Rheumatism (EULAR) jointly endorsed a new set of criteria for the classification of primary Sjögren's syndrome (SS) derived through international consensus. These criteria are based on testing of the saliva, blood and eyes.
ACR/EULAR classification criteria for primary Sjögren's syndrome
Item
Weight/Score
Saliva
Labial salivary gland (salivary glands near the mouth) A focal lymphocytic sialadenitis and focus score of ≥1
Anti-SSA/SSB (Ro) positive (antibodies to Ro/SSA antigen)
1
Eyes
Ocular staining (measures damage to the surface of the eye) A score ≥5 (or van Bijsterfeld score ≥4) on at least one eye
1
Schirmer’s test (measures tear production) ≤5 mm/5 minutes on at least one eye
1
The diagnosis of primary Sjögren's syndrome applies to any person who meets the inclusion criteria (has some of these symptoms) and who has a score of four or greater when the weights/scores from the five criteria are totaled.