The parotid gland disease formerly known as “Mikulicz’s syndrome” now is usually included with Sjogren’s Syndrome. Some reports indicate that Sjogren’s Syndrome affects 2%-5% of adults over age 55 and is second only to RA in frequency among the rheumatoid-collagen diseases. SSjogren’s Syndrome occurs in primary and secondary forms. Primary Sjogren’s Syndrome, sometimes called the “sicca syndrome,” involves both the major and minor salivary glands, the lacrimal glands, and the labial glands. There is destruction of the salivary gland parenchymal cells with dense lymphoid reaction. Loss of lacrimal gland function makes the patient unable to produce tears and leads to injury of the cornea and conjunctiva (keratoconjunctivitis sicca). There are many other abnormalities that appear in a minority of patients, such as renal tubular acidosis, pericarditis, chronic hepatobiliary disease with antimitochondrial antibodies present, pancreatitis, disturbances of esophageal motility, and an increased tendency for lung infections. About 20% of patients with primary Sjogren’s Syndrome develop multifocal brain and spinal cord dysfunction closely resembling multiple sclerosis, both from clinical and laboratory aspects. Some of these patients develop cerebrospinal fluid oligoclonal bands and elevated IgG production indices.

Secondary Sjogren’s Syndrome is the coexistence of substantial components of primary Sjogren’s Syndrome with some other disease. The disorders that overlap with Sjogren’s Syndrome include most conditions that have a strong autoimmune component. The diseases most frequently reported to be associated with Sjogren’s Syndrome are RA (10%-25% of RA patients) and SLE (up to 30% of SLE patients). Some investigators report elements of Sjogren’s Syndrome in many patients with PSS and primary biliary cirrhosis.

Laboratory aspects. Patients with Sjogren’s Syndrome have various detectable autoantibodies. About 50%-80% have a positive ANA test result, about 15%-20% have positive LE prep test results, and about 75%-90% have detectable rheumatoid factor. About 25% have anti-dsDNA antibodies. The most characteristic autoantibodies are SS-A (Ro) and SS-B. The SS-A antibody is reported in about 75% (13%-88%) of patients with primary Sjogren’s Syndrome, about 10% of Sjцgren’s syndrome with RA, and about 50% of patients with SLE. The SS-B antibody is found in about 60% (literature range, 48%-73%) of patients with primary Sj?gren’s syndrome, 75%-85% of SLE Sj?gren’s syndrome, and 2%-8% of SLE without Sj?gren’s syndrome. RAP autoantibodies are reported in 60%-80% of Sjogren’s Syndrome with RA and 5%-30% of Sjogren’s Syndrome without RA. Therefore, elevated SS-A or SS-B antibody levels, especially in high titer, suggest primary Sjogren’s Syndrome or Sj?gren’s syndrome with SLE, with SS-B less sensitive but more specific for primary Sj?gren’s syndrome. RAP autoantibodies are useful markers for the RA-associated secondary form of Sjogren’s syndrome. The data on autoantibodies in primary and secondary Sjogren’s Syndrome are rather contradictory except for larger trends, probably due to differences in antigens used in the research laboratories and differences in diagnostic criteria in the populations tested. Standardized test reagents and diagnostic criteria are needed for final evaluation of these tests.

Diagnosis of Sjogren’s Syndrome can be made from clinical symptoms, biopsy of salivary or labial glands, or presence of SS-A or SS-B autoantibodies in high titer. The SS-B is more specific for Sjogren’s Syndrome than SS-A but is less sensitive. High titers of SS-B suggest primary Sjogren’s Syndrome or SLE with Sjogren’s Syndrome.