Background Data regarding the prevalence, risk factors and outcome of scleroderma renal crisis (SRC) in Asian patients with systemic sclerosis (SSc) are limited.
Objectives To determine the prevalence, risk factors and outcome of SRC in Thai SSc patients.
Methods Medical records of all SSc patients, fulfilling the 1980 American College of Rheumatology classification criteria for SSc, seen at the Division of Rheumatology, Maharaj Nakorn Chiang Mai Hospital, Thailand, from January 1990 and December 2015 were retrospectively reviewed. Patients younger than 18 years old or overlapping with rheumatoid arthritis, systemic lupus erythematosus or mixed connective tissue disease were excluded. Cases of SRC were identified based on the international Scleroderma Renal Crisis Study criteria1. Controls were selected from consecutive SSc patients without SRC from our database that was ranked closest to the cases based on hospital number, and matched for disease duration from the first non-Raynaud's phenomenon, by±1 year. The ratio for SRC patients to control patients was 1:4.
Results Of 608 SSc patients seen during the study period, 19 SRC were identified resulting of the SRC prevalence of 3.13% and there were 76 matched controls. Of the 19 cases, mean±SD age and median (IQR1, 3) disease duration was 56.2±13.8 years and 9 (5.0, 16.0) months, respectively. Seventeen patients (89.5%) had dcSSc. There were 12 (63.2%) patients with hypertensive renal crisis (HRC) and 7 (16.8%) patients with normotensive renal crisis (NRC). Univariate conditional logistic regression analyses showed that current myositis (Odd ratio [OR]21.75, 95% CI 2.65– 178.71,p=0.004), cardiac involvement (OR5.68, 95% CI2.03 – 15.84,p=0.001), age >60 years (OR2.82,95% CI 1.01 – 7.94,p=0.049), WBC>10,000 cell/mm3 (OR2.69,95% CI 0.99 – 7.26,p=0.050), serum albumin<3.0 mg/dl (OR11.08,95% CI 3.02 – 40.66,p<0.001), and current prednisolone used≥15 mg/day (OR19.36,95% CI 2.29 – 163.66,p=0.007) were associated with SRC. Digital gangrene tended to show an association with SRC in the univariate analysis (OR8.00,95% CI0.72 – 88.22,p=0.090). Variables with p<0.15 in univariate conditional logistic regression analysis were included in the multivariate conditional logistic regression analysis. When multivariate conditional logistic regression analysis was performed, digital gangrene (adjusted odd ratio [AOR]31.41,95% CI 1.16 – 852.23,p=0.041), current prednisolone use≥15 mg/day (AOR31.22, 95% CI 1.59 – 613.85,p=0.024), serum albumin <3 mg/dl (AOR7.97, 95% CI 1.49 – 42.56,p=0.015) and cardiac involvement (AOR 6.62,95% CI1.08 – 40.63,p=0.041) were confirmed to be independent risk factors for SRC. During a median (IQR 1, 3) follow-up of 1 (0, 2) months, 15 (78.9%) patients required hemodialysis, including 9 of 12 (75.0%) patients with HRC and 6 of 7 (85.7%) with NRC. Twelve (63.2%) patients received ACEI, including 9 of 12 (75.0%) patients with HRC and 3 of 7 (42.9%) patients with NRC. Ten (52.6%) patients died, including 5 of 12 patients (41.7%) with HRC and 5 of 7 (71.4%) patients with NRC.
Conclusions SRC was an uncommon complication in Thai patients with SSc, but associated with high mortality. Digital gangrene, current prednisolone used≥15 mg/day, serum albumin<3 mg/dl and cardiac involvement were independent risk factors of SRC.
Hudson M, et al.Semin Arthritis Rheum 2014.
Disclosure of Interest None declared