Sjögren's syndrome (SS) is a chronic autoimmune disorder characterized by the triad of dry eyes (keratoconjunctiva sicca), sensation of oral dryness (xerostomia) and/or swelling of the salivary glands secondary to lymphocytic infiltration and destruction of the exocrine glands.
Prevalence of SS is estimated at 0.5-1.5% of the population in the Western World.
SS primarily affects women, with a 9:1 female to male ratio, presenting most often after the fourth decade with slowly progressive symptoms involving exocrine glands: keratoconjunctivitis sicca, xerostomia, and parotid gland enlargement. Other common manifestations include submandibular swelling, dry cough, erythematous oral mucosa membranes, high incidence of caries, atrophy of esophageal mucous, atrophic gastritis, vaginal dryness and dyspareunia in females. Xerosis with pruritus is also observed, other skin findings may include Raynaud's phenomenon, purpura (flat or palpable) and dermal vasculitis. Non-exocrine symptoms appear in more than 50% of patients, more frequently in those presenting at <35 years, complaints include chronic fatigue, mild fever and persistent myalgia. Joint pain and stiffness have also been reported in more than half of patients. Neurological complaints present in 20% of cases: non-ataxic sensory neuropathy with tingling, burning sensations and less frequently asymmetric paresthesias. Some patients (7.5%) develop a lymphoma during the course of their disease, usually mucosa associated tissue lymphoma (MALT; see this term). Less common symptoms include pulmonary involvement (bronchitis, pneumonia), kidney dysfunction and hepatitis. Recurrent miscarriage has been reported in rare cases, with elevated incidence of fetal heart block.
SS is an autoimmune disease that may occur independently (primary SS, pSS, see this term) or associated with another disorder (secondary SS, sSS, see this term) such as rheumatoid arthritis, systemic lupus erythematosus and systemic sclerosis (see these terms).
In addition to chronic keratoconjunctivitis sicca and xerostomia, objective criteria include positive serum anti-SSA and/or anti-SSB; corneal staining scores of 4 or greater; a salivary flow rate of <1.5 ml/15 min and the presence of focal lymphocytic sialadenitis with 1 focus/4 mm2 or greater in labial salivary gland biopsy samples. Standard diagnostic criteria are established by the American-European Consensus Group classification criteria for SS. A new classification set has been proposed by the American College of Rheumatology applying only objective criteria.
Differential diagnoses include hepatitis C infection, HIV infection, HTLV-1 infection, pseudolymphomas, Hodgkin lymphoma, hyper IgG4 related disease and sarcoidosis (see these terms).
Management is limited to symptomatic treatment: artificial tears, salivary stimulants, saliva substitutes, strict oral hygiene and bi-annual dental visits. Pilocarpine and cevimeline may be given to increase saliva and tears. Punctual occlusion surgery may be undertaken to treat severe keratoconjunctivitis sicca. Non-steroidal anti-inflammatory drugs can be used to treat joint pain and stiffness. Systemic treatments may include corticosteroids, hydroxychloroquine, immunosuppressants such as cyclophosphamide, methotrexate, leflunamide, azathioprine or cyclosporine, and biologicals (e.g. rituximab). Patients with adverse prognosis predictors such as purpura, low C4-complement levels or mixed monoclonal cryoglobulins are at higher risk of developing lymphoma and must be followed regularly.
Overall prognosis is good but the main symptoms of dryness, fatigue and pain are disabling. More than 50% of cases develop systemic features whose symptoms have an important impact on the function of different organs and on quality of life. MALT (see this term) development is associated with a more active SS, with more systemic manifestations and a higher risk of mortality.
Last update: November 2013
- Pr H. [Hendrika] BOOTSMA
- Pr Arjan VISSINK