Late onset lupus nephritis: analysis of clinical manifestations and renal pathological features in Chinese patients

The objectives of the study are to analyze the clinical and pathological features of 35 Chinese patients with late onset lupus nephritis (LN) in a single center. All the LN patients followed-up in our lupus clinic center from 1986 to 2008 were enrolled in this retrospective study. Thirty-five patients with a disease onset beyond the age of 50 years were identified. One hundred systemic lupus erythematosus (SLE) patients who had their disease onset before the age of 50 years were randomly recruited as controls. All of them received renal biopsy. The histological classifications were categorized according to 2003 International Society of Nephrology/Renal Pathology Society (ISN/RPS) classification. All of patients were Han Chinese. The mean age of onset of SLE for late onset and the control groups were 55.7 ± 6.5 years (range: 50–76) and 28.9 ± 7.6 years (range:18–48).The female to male ratio was smaller in the late onset SLE group, 2.9–1, compared with 7.3–1 in the control. The patients with hypertension in late onset LN were much more than that in control group. The renal histological classes showed no significant difference between the two groups. Classes IV, V, IV + V were common in late onset LN patients. There were no significant differences in extra renal manifestations except for a lower prevalence of malar rash, a higher leukopenia and skin vasculitis in the late onset patients. As to the immunological features, serum antineutrophil cytoplasmic antibodies (ANCA) and SSA positivity were more common in late onset LN patients. The patients with hypertension in late onset LN were much more than that in control group. The renal histological classes showed no significant difference between the two groups. Leukopenia and serum ANCA were more common. The results suggest a more severity of the disease in late onset LN.