Early diagnosis of Sjögren's remains a challenge

Sjögren's is one of the most commonly under-diagnosed autoimmune diseases, often taking 5 to 8 years before a diagnosis is made.

While there are several techniques to assess salivary gland and ocular involvement, tests for certain autoantibodies in serum, and methods to demonstrate tissue changes, no single test is specific and sensitive enough to make a diagnosis.

Lack of international consensus regarding what defined positive evidence of the illness and ways to differentiate the two variants of the illness were some of the reasons for revision of the classification criteria for Sjögren's.

In April 2012, the latest version of the classification criteria was released by a group of international experts which included new details, rules and thresholds for tests and how these need to performed and interpreted. (Source: The Kelley's Textbook of Rheumatology, 9th edition).

The new criteria was intended, in part, to help ensure uniformity in participants selected for research.

To meet the classification criteria, there must be objective evidence in 2 out of 3 tests. For example, one of these tests must show one or more sites of inflammation per 4 mm squared area of glandular tissue for a positive result, according to the National Institutes of Health's release of April 2012, "New classification criteria released for research on Sjögren's Syndrome."

Clinicians and researchers who treat Sjögren's patients find these criteria can only detect patients with an established disease, that is, when their glands have already become damaged.

Patients will typically need to consult with at least two clinical specialties for evaluation and testing before a diagnosis can be made. The high cost of diagnostic tests, risks and discomfort associated with some of the procedures, and amount of time required to complete the testing/diagnostic process causes significant delay in diagnosis.

Continued disagreement and proposed changes to the 2012 classification criteria has gotten in the way of research for new treatments. All of the aforementioned issues underscore the importance of finding new ways to diagnose Sjögren's at an early stage of the illness.