Sjögren’s syndrome (SS) is a chronic autoimmune inflammatory disorder characterized by diminished lacrimal and salivary gland function. The diminished exocrine gland function leads to the “sicca complex,” a combination of dry eyes and dry mouth [1,2]. In addition, a variety of other disease manifestations affecting multiple organs and organ systems may occur, and the clinical features of SS can be divided into the two broad categories of exocrine glandular features and extraglandular features . (See "Clinical manifestations of Sjögren's syndrome: Exocrine gland disease" and "Clinical manifestations of Sjögren's syndrome: Extraglandular disease".)
Disease severity can vary over a wide range:
●At the mild to moderate end of the spectrum are patients with symptoms of dry eyes, dry mouth, a low titer of antinuclear antibody, and symptoms of fatigue, myalgia, and mild cognitive dysfunction. At times, such patients may be difficult to distinguish clinically from patients with fibromyalgia or depression who have ocular and/or oral dryness caused or exacerbated by medications with anticholinergic side effects.
●A severely affected patient may have florid salivary gland enlargement, adenopathy, antibodies to the Ro/SSA and La/SSB antigens, cryoglobulinemia, hypocomplementemia, a propensity to develop non-Hodgkin lymphoma, and other extraglandular disease manifestations.
●A small group of patients have primarily extraglandular manifestations and positive testing for antinuclear and Ro/SSA antibodies without significantly dry eyes or dry mouth. The laboratory findings may be found during evaluation of neuropathies, nephropathies, interstitial pneumonitis, hematologic abnormalities, lymphoproliferative changes, or abnormalities of other organs with a pattern of extraglandular disease suggestive of either SS or systemic lupus erythematosus.