Criteria for Diagnosis
The American College of Radiology (ACR) and European League Against Rheumatism (EULAR) classification criteria for primary Sjögren syndrome are listed in the table below. These criteria apply to patients considered to have oral or ocular dryness according to the ACR/EULAR definition. The classification does not apply to patients with another rheumatologic diagnosis with overlapping symptoms, nor to patients with conditions such as active hepatitis C virus with polymerase chain reaction (PCR) confirmation, AIDS, sarcoidosis, amyloidosis, IgG4-related disease, graft-versus-host disease, or history of head and neck radiation. These criteria are not yet validated for secondary Sjögren syndrome.
ACR/EULAR Classification Criteria for Primary Sjögren Syndrome
|
| Criteria |
Score |
|---|
|
Anti-SSA (Ro) positivity
|
3
|
|
Labial salivary gland with focal lymphocytic sialadenitis and focus score ≥1 foci/4 mm2
|
3
|
|
Whole saliva flow rate (unstimulated) ≤1 mL/minb
|
1
|
|
Ocular staining score ≥5 or van Bijsterveld score ≥4b,c
|
1
|
|
Schirmer’s test rate ≤5 mm/5 minb,c
|
1
|
|
|
aScore of ≥4 designates individual as having primary Sjögren syndrome.
bPatients receiving anticholinergic drugs should be assessed only after a period without these drugs for an accurate evaluation.
cIn at least 1 eye.
Source: Shiboski, 2017
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Indications for Testing
Testing for Sjögren syndrome should be considered for patients with dry mouth and dry eyes, especially if these symptoms are accompanied by fatigue, joint pain, and/or signs of systemic complications. As many as 30-40% of patients with primary Sjögren syndrome have systemic complications.
Laboratory Testing
Diagnosis
Antinuclear Antibody Tests
ANAs are not specific to Sjögren syndrome but are seen in a variety of other SARDs, as well as in organ-specific autoimmune diseases, some infections or malignancies, in elderly patients, and even in some healthy individuals. For that reason, ANA testing is best used in patients with a strong likelihood of having Sjögren syndrome or another SARD.
ANA tests may show a speckled pattern in patients with Sjögren syndrome. Cytoplasmic and other nuclear patterns may also be associated with Sjögren syndrome. (For comprehensive information on patterns and their clinical associations, refer to the International Consensus on ANA Patterns website. )
The gold standard for ANA testing is the indirect fluorescent antibody (IFA) assay. Methods other than IFA to detect ANAs are considered less sensitive for particular disorders but can be more specific and have faster turnaround times.
ENA testing is used to follow up on positive ANA results. ENA test results can help to differentiate between various SARDs, for instance, Sjögren syndrome and SLE. Panels that test for several ENAs can be helpful for identifying these disorders. The presence of anti-SSA (Ro) (SSA-52 and SSA-60) and anti-SSB (La) is useful for distinguishing Sjögren syndrome. Anti-SSA antibodies are found in two thirds of patients with Sjögren syndrome, and anti-SSA (Ro) positivity is an important component of the ACR/EULAR classification criteria for primary Sjögren syndrome. (See Criteria for Diagnosis above.)
Rheumatoid Factor Test
RF testing is commonly used as part of the workup for Sjögren syndrome, as RF is found in approximately half of patients with the disease.
Additional Tests
Sjögren syndrome diagnosis requires tests in addition to antibody and RF tests (see Criteria for Diagnosis above). Suggested tests include the measurement of unstimulated whole saliva flow rate to assess oral dryness, ocular staining to evaluate damage to the ocular surface caused by eye dryness, Schirmer’s test to measure tear production, and a labial salivary gland biopsy to detect focal lymphocytic sialadenitis and determine a focus score.
Monitoring
Surveillance for B-cell lymphoma is particularly important in patients with Sjögren syndrome, as the incidence of B-cell lymphoma is 15-20 times higher in those with Sjögren syndrome than in the general population. Tests that are useful for B-cell lymphoma screening include lymphocyte count, protein electrophoresis, RF, C3 and C4 protein, and cryoglobulin.
ENA testing can also be used for monitoring patients with Sjögren syndrome (see Extractable Nuclear Antibody Tests above).
A tool called the EULAR Patient Reported Index is useful for general monitoring to evaluate mouth and eye dryness as well as fatigue and pain. A second index for Sjögren syndrome, the EULAR Sjögren’s Syndrome Disease Activity Index (ESSDAI), assesses 12 organ domains, but is used primarily in clinical trials. )
