Sjogren's syndrome-onset lupus patients have distinctive clinical manifestations and benign prognosis: a case-control study.

The objective of this study was to investigate the clinical characteristics and prognosis of Sjögren's syndrome-onset systemic lupus erythematosus (SS/SLE) patients. Medical charts of 41 consecutive SS/SLE inpatients admitted to Peking Union Medical College Hospital (PUMCH) from February 1998 to February 2008 were systematically reviewed, including demographic data, clinical features, laboratory findings, treatment as well as outcomes. Two hundred and fourteen cases were randomly selected as controls from 2331 SLE-only inpatients treated in PUMCH at the same time period. There were significant differences between SS/SLE and SLE-only patients in the following manifestations (p < 0.05): (1) sex ratio (F/M) (41/0 versus 184/30), age (42.8 +/- 41.0 years versus 31.8 +/- 31.0 years), disease duration (113.8 +/- 84.0 months versus 44.9 +/- 18.0 months); (2) clinical features, xerostomia (85.4% versus 6.1%), xerophthalmia (75.6% versus 2.3%), renal tubular acidosis (21.9% versus 0%), interstitial lung disease (12.2% versus 2.8%), facial rash (9.8% versus 46.3%), nephrotic syndrome (7.3% versus 31.3%), central nervous system involvement (4.9% versus 19.6%); (3) laboratory findings, ESR (64.6+/-75.0mm/h versus 46.5+/-34.0mm/h), C4 (14.8 +/- 12.2 g/dl versus 12.0 +/- 10.9 g/dl), IgG elevation (56.4% versus 29.9%) and IgA elevation (38.5% versus 20.4%), RF, anti-SSA and anti-SSB positive rates (70.8% versus 20.3%, 82.9% versus 43.4% and 39.0% versus 7.9%); (4) SLEDAI score (8.0 +/- 8.0 versus 10.2 +/- 10.0), glucocorticoid treatment (methylprednisolone bolus/1-2 mg kg(-1) day(-1) prednisone/<1 mg kg(-1) day(-1) prednisone) (8/26/7 versus 91/102/21), and importantly, rate of death and/or severe irreversible organ failure (2.4% versus 14.9%). SS/SLE patients were followed up for 33.0 +/- 34.0 months, 40 cases remained stable at a low dose of corticosteroid. In conclusion, different from SLE-only patients, SS/SLE patients have distinctive clinical manifestations and benign prognosis that require less vigorous treatment with glucocorticoids and/or immunosuppressants.