Clinicopathologic features of antineutrophil cytoplasm autoantibody (ANCA)-associated acute renal failure in Chinese patients

Abstract

The clinical course and renal pathologic features of anti-neutrophil cytoplasm auto-antibody (ANCA)-associated renal disease were studied among Chinese patients from a single centre. Eight ANCA positive patients with acute renal impairment were studied, four of whom required dialysis shortly after presentation. Their mean age at presentation was 61.6 ± 4.2 years. Renal histology, obtained in seven patients, showed paucummune crescentic glomerulonephritis in five patients, interstitial nephritis in two patients, and small vessel vasculitis in one patient. Pulmonary baemorrhage was the other common disease manifestation, present in four of the eight patients, necessitating ventilatory support in three patients. Neurologic, cutaneous, and gastrointestinal involvement were also observed. Seven of the eight patients tested positive for pANCA and anti-myeloperoxidase, while cANCA was detected in one patient of the eight patients, six (75%) responded to therapy, consisting of prednisolone and cyclophosphamide in five patients, and antibacterial therapy alone in one patient, who had interstitial nephritis but no evidence of vasculitis. Two patients died from sepsis and severe debilitation one month after presentation. of the other six patients, five had significant improvement of renal function, while one became dialysis-dependent. the levels of ANCA and C-reactive protein remained normal, and disease reactivation was not observed during follow-up for 32.4 ± 6.1 months. Patient and renal survival rates at one year were 75% and 62.5%, respectively. It was concluded that the clinical and pathologic features of ANCA-associated renal disease in Chinese patients are, in general, similar to those described in Caucasians. Nevertheless, cANCA-positivity is distinctly uncommon. the demonstration of interstitial nephritis in two of the eight patients underlines the importance of renal biopsy for correct histologic diagnosis. Early institution of aggressive immunosuppression and supportive therapies are essential for the achievement of favourable outcome in patients with vasculitis.