Primary Sjögren's syndrome.

Primary Sjögren's syndrome (pSS) is a relatively common autoimmune systemic rheumatic disease. In addition to sicca syndrome and swollen salivary glands, systemic features manifest in the majority of patients, and are severe in 15%, particularly affecting the joints, skin, lungs, and peripheral nervous system. A recent meta-analysis estimated a pooled relative risk of 13.76 for the development of non-Hodgkin lymphoma, particularly in pSS patients who have parotid enlargement, vasculitis, cryoglobulinemia, and antibodies to Ro and La. pSS is the underlying diagnosis in one-third of mothers of neonates affected by congenital heart block. The diagnosis of pSS is complex and requires a stepwise approach to evaluate symptoms of ocular and oral dryness, objective measures of lacrimal and salivary gland dysfunction, and evidence of autoimmunity with Ro/La autoantibodies and labial salivary gland biopsy. It is essential to eliminate other autoimmune diseases, as well as non-autoimmune causes of sicca syndrome, such as menopause, endocrine diseases, anticholinergic effects of drugs, and fibromyalgia, to delineate pSS patients who are at risk of systemic complications. Recent major advances in the diagnosis of pSS have been the development of classification criteria, which serve as a template for clinical diagnosis, and outcome measures for use in clinical trials and prospective patient cohorts. Clinical data and biological samples from longitudinal cohorts, embedded into clinical practice, will be essential to further improve the diagnosis and management of pSS, increase knowledge about the natural history of the disease, gain insights into its pathogenesis, and stratify patients according to their risk of systemic disease and NHL. At present, there is a gap in evidence regarding the role of structured protocols in the management of pSS. Recent recommendations for the management of sicca symptoms and clinical trials of disease-modifying therapy are discussed.