Sjögren's syndrome (pronounced /ˈʃoʊɡrɨnz/ shoh-grinz in English), also known as "Mikulicz disease" and "Sicca syndrome", is a systemic autoimmune disease in which immune cells attack and destroy the exocrine glands that produce tears and saliva.
It is named after Swedish ophthalmologist Henrik Sjögren (1899–1986), who first described it.
Nine out of ten Sjögren's patients are women and the average age of onset is late 40s, although Sjögren's occurs in all age groups in both women and men.[citation needed] It is estimated to affect as many as 4 million people in the United States alone, making it the second most common autoimmune rheumatic disease.
Sjögren's syndrome can exist as a disorder in its own right (primary Sjögren's syndrome) or may develop years after the onset of an associated rheumatic disorder, such as rheumatoid arthritis, systemic lupus erythematosus, scleroderma, primary biliary cirrhosis etc. (secondary Sjögren's syndrome).[citation needed]
The disorder should not be confused with the Sjögren–Larsson syndrome, which was also denoted T. Sjögren syndrome in early studies.