Few studies have reported on the long-term prognosis of anti-neutrophil cytoplasmic antibody (ANCA)-negative renal vasculitis. Between April 2003 and December 2013, 48 patients were diagnosed with renal vasculitis. Their ANCA status was tested using indirect immunofluorescence and enzyme-linked immunosorbent assays. During a median (interquartile range) follow-up duration of 933.5 (257.5-2,079.0) days, 41.7% of patients progressed to end stage renal disease (ESRD) and 43.8% died from any cause. Of 48 patients, 6 and 42 were ANCA-negative and positive, respectively. The rate of ESRD within 3 months was higher in ANCA-negative patients than in ANCA-positive patients (P = 0.038). In Kaplan-Meier survival analysis, ANCA-negative patients showed shorter renal survival than did ANCA-positive patients (log-rank P = 0.033). In univariate Cox-proportional hazard regression analysis, ANCA-negative patients showed increased risk of ESRD, with a hazard ratio 3.190 (95% confidence interval, 1.028-9.895, P = 0.045). However, the effect of ANCA status on renal survival was not statistically significant in multivariate analysis. Finally, ANCA status did not significantly affect patient survival. In conclusion, long-term patient and renal survival of ANCA-negative renal vasculitis patients did not differ from those of ANCA-positive renal vasculitis patients. Therefore, different treatment strategy depending on ANCA status might be unnecessary.
Age Factors ; Aged ; Antibodies, Antineutrophil Cytoplasmic/*analysis ; Cohort Studies ; Enzyme-Linked Immunosorbent Assay ; Female ; Follow-Up Studies ; Humans ; Kaplan-Meier Estimate ; Kidney Diseases/*diagnosis/mortality ; Kidney Failure, Chronic/etiology ; Male ; Microscopy, Fluorescence ; Middle Aged ; Prognosis ; Proportional Hazards Models ; Republic of Korea ; Retrospective Studies ; Risk Factors ; Severity of Illness Index ; Sex Factors ; Vasculitis/complications/*diagnosis/mortality