Noninvasive Test for Sjogren's Syndrome

A faster, more accurate, and noninvasive test for Sjogren's syndrome analyzes multiple protein biomarkers in the tears by mass spectrometry.

Sjogren's syndrome is an incurable autoimmune disorder characterized by chronically dry eyes and dry mouth. The disease affects one to four million people in the United States alone, primarily women over the age of 40.

Sjogren's syndrome can be difficult to diagnose. Current methods of diagnosing the disease involve a battery of tests, including painful invasive techniques using needles or biopsies to analyze bodily tissues and fluids, particularly in the eyes and mouth. Diagnosis has been further complicated by the lack of biomarkers specific for the disease and the slow progression of the disease.

The new test requires that patients shed as little as a single teardrop, collected in a doctor's office using special filter papers. The teardrop is then analyzed in a laboratory for a newly discovered protein biomarker, with results available in as little as one hour. In a study, Japanese researchers analyzed the protein content of tears obtained from 31 patients diagnosed with Sjogren's syndrome by conventional tests and compared the results to protein markers obtained from the tears of 57 subjects who did not have the syndrome. Using surface enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS), the researchers identified about 10 protein biomarkers that appear to be specific for Sjogren's syndrome.

"The development of an accurate and noninvasive diagnostic test would be of considerable value in the clinical field,” said study leader Naohisa Tomosugi, M.D., of Kanasawa Medical University (Japan).

In addition to helping diagnose the disease, the tear biomarkers also show potential for noninvasive monitoring of disease activity and progress, according to the researchers. The study results were reported in the June 13, 2005, issue of the Journal of Proteome Research, a publication of the American Chemical Society.




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Kanazawa Univ.