Outcome of ANCA-Associated Primary Renal Vasculitis in Miyazaki Prefecture

Object We examined the prognosis of patients with onset of new primary renal vasculitis (PRV) in Miyazaki Prefecture. Patients and Methods We enrolled and followed-up 56 patients (age, 70.4 ± 10.9 years, mean ± SD) with onset of new PRV between January 2000 and December 2004, for a median of 24 months. Patients with PRV were defined according to the EUVAS (European Systemic Vasculitis Study Group) criteria. Outcome and factors predicting unfavorable outcome of death were examined. Results Among the patients, 25% (n=14) required dialysis therapy immediately at the start of immunosuppressive therapy and of these, renal function recovered in only 3 and 6 died during the first admission. On the other hand, 75% (n=42) did not require immediate dialysis, but 8 patients were introduced to dialysis therapy thereafter. At the end of follow-up, 26 (46%) had survived without dialysis, 10 (18%) were dependent on dialysis and 20 (36%) had died. Infection was the major cause of death (n=11) . The Cox proportional hazards model showed that the presence of lung lesions and immediate dialysis therapy conferred poorer survival rates (HR, 3.32, 95% CI, 1.14 to 9.71; HR 2.73, 95% CI, 1.03 to 7.23, respectively). Conclusion A poor survival rate is independently associated with the presence of lung lesions and advanced renal failure at the start of immunosuppressive therapy in patients with PRV. Half of the deaths were due to infection. Thus, PRV should be identified at an early stage and the treatment protocol should prevent infectious complications. These measures should improve the prognosis of patients with PRV.