Objective: To study the clinical features, treatment and outcomes of primary Sjögren's Syndrome (pSS) in a Singapore cohort from an outpatient rheumatology clinic.
Methods: Computerised Physician Order entry records of patients who fulfilled the 2016 ACR-EULAR classification criteria for pSS between 1993 and 2013 were retrospectively analysed.
Results: There were 102 patients, of which 96 (94.1%) were females, and 91 (89.2%) Chinese. Mean age at diagnosis was 49.3 ± 11.8 years, mean disease duration was 9.0 ± 4.6 years. The most common manifestations were keratoconjunctivitis sicca (99.0%), xerostomia (96.1%), arthralgia/arthritis (56.9%). Exocrine glandular enlargement comprised parotidomegaly (28, 27.5%), with concurrent submandibular and lacrimal gland enlargement in one. The nervous system (15.7%) was the most commonly affected internal organ, with peripheral nervous system (peripheral neuropathy, mononeuritis multiplex) involvement more common than central. Hydroxychloroquine was most frequently used (88.2%), followed by methotrexate (7.8%) and azathioprine (6.9%). Pulsed intravenous (IV) methylprednisolone 500 mg/day for 3 days was used in 5 patients followed by oral (4) or IV cyclophosphamide (1) for cardiomyopathy and interstitial lung disease (1), and neurological involvement (4). These comprised neuromyelitis optica, transverse myelopathy, cranial neuropathy, mononeuritis multiplex and/or peripheral neuropathy alone or in combination. Intravenous immunoglobulins (2.0%) was used for sensory neuropathy and mononeuritis multiplex; rituximab (1.0%) in 1 patient for treatment of non-Hodgkin's B-cell lymphoma. There were no deaths.
Conclusion: Musculoskeletal manifestations were common, with the nervous system (peripheral more than central) the most common internal organ involved. Lymphoma was uncommon despite up to one-third of the cohort developing glandular enlargement.
Keywords: Epidemiology; lymphoma; neuromyelitis optica; peripheral neuropathy; therapeutics.