Prevalence, risk factors and outcome of digital gangrene in 2684 lupus patients.

The aim of the study is to assess the clinical characteristics, risk factors and outcome of patients with systemic lupus erythematosus (SLE) complicated with digital gangrene. In all, 2684 consecutive SLE inpatients admitted to Peking Union Medical College Hospital from December 1997 to August 2007 were studied. Demographic data, clinical features, laboratory findings as well as therapeutic regimens were systematically reviewed and a database was established. Cases with digital gangrene were identified and followed up. 1) Eighteen patients with SLE were complicated with digital gangrene, the average age at event was 33.1 +/- 11.8 years and the average disease duration was 99.1 +/- 60.1 months. 2) Patients with SLE, with long disease duration (> or =4 years), Raynaud's phenomenon and elevated serum C-reactive protein (CRP) were more likely to develop digital gangrene, P = 0.006, 0.001, and 0.031, respectively, OR = 1.03 (95% CI 1.01, 1.04), 35.76 (95% CI 4.67, 273.83) and 9.93 (95% CI 1.23, 80.30), respectively. 3) Fifteen gangrene patients started prednisone > or =1 mg/kg/d, and 18 were treated with cyclophosphamide, although 8 cases failed and ultimately received digital amputation. Prompt corticosteroid treatment (prednisone > or = mg/kg/d started within 3 weeks) decreased the hazard of amputation, P = 0.073, HR = 0.13 (95% CI 0.01, 1.21). Long disease duration, Raynaud's phenomenon and elevated serum CRP were independent predictive factors for SLE to develop digital gangrene. Early and aggressive corticosteroid treatment prevented gangrene from progression and improved prognosis.