Characteristics and Prognosis of Chinese Patients with Anti-Glomerular Basement Membrane Disease

Abstract

Background: Patients with anti-glomerular basement membrane (GBM) disease were predominantly reported in Caucasian population and reports from Chinese were lacking. The general picture of Chinese patients with anti-GBM disease was still unclear. This study is to investigate the characteristics and prognosis of Chinese patients with anti-GBM disease. Methods: Data from 105 patients with anti-GBM disease diagnosed in our hospital, between 1997 and 2002, were analyzed retrospectively. All the 105 sera were screened by enzyme-linked immunosorbent assay (ELISA) using highly purified bovine α(IV)NC1 as solid phase ligands. Clinical and pathological data of 69 patients with complete clinical remission (n = 5), partial remission (n = 10), and treatment failure (n = 54) were compared and the prognostic factors were evaluated. Results: Patients increased chronologically and three quarters of the 105 patients were diagnosed in the last 3 years. Most of the patients were between 20 and 29 years (n = 31) and a smaller second peak was found in patients over 60 years. 25/105 (24%) were also ANCA-positive. Patients with both anti-GBM antibodies and ANCA positive were elder (50 ± 19 vs. 34 ± 15 years, p < 0.01) and female predominant (15/25 vs. 16/80, p < 0.05). 56/97 (58%) patients presented as Goodpasture syndrome, 40/97 (41%) patients presented as rapidly progressive glomerulonephritis and one patient had pulmonary hemorrhage only. The following factors predict poor prognosis: (1) serum creatinine more than 600 µmol/l on diagnosis (p < 0.01); (2) oliguria or anuria on diagnosis (p < 0.01); (3) a high percentage (>85%) of glomeruli had crescents (p < 0.01), and (4) renal involvement before pulmonary hemorrhage (p < 0.05). Patients with serum creatinine over 600 µmol/l on diagnosis had higher levels of anti-GBM antibodies (106 ± 48% vs. 73 ± 40%, p < 0.01). Intensive plasma exchange therapy predicts a better prognosis in the patients with serum creatinine less than 600 µmol/l (p < 0.05). Conclusions: Anti-GBM disease is not rare in China and behaves similarly to elsewhere. Early diagnosis and intensive plasmapheresis might be the most promising approaches to improve the outcome.