Focal proliferative lupus nephritis. A clinicopathologic study using the W.H.O. classification.

Focal proliferative lupus glomerulonephritis has traditionally been considered to be more benign than the diffuse form. A recent study of lupus nephritis using the W.H.O. classification demonstrated no difference in 4-year survival between those with focal and those with diffuse disease. Because of this development, a comparative clinicopathologic study of 15 patients with focal proliferative lupus glomerulonephritis was done using the W.H.O. classification. Generally, patients with focal proliferative lupus glomerulonephritis presented with milder renal disease with respect to proteinuria and renal insufficiency. Involvement of the central nervous system was more prominent in focal proliferative lupus glomerulonephritis. Therapy for both types of disease was similar. Mean duration of renal disease was 48 months for focal and 50.7 months for diffuse disease. Three patients with focal proliferative lupus glomerulonephritis and two with diffuse proliferative lupus glomerulonephritis were dead at the end of the follow-up period. Established renal failure was present in one patient with focal disease and two with diffuse disease. Deterioration of renal function was noted in two patients with focal proliferative lupus glomerulonephritis and five with diffuse proliferative lupus glomerulonephritis at the end of the follow-up period. No statistically significant differences in cumulative five-year survival rates (focal = 0.751; diffuse = 0.858), cumulative five-year renal survival rates (focal = 1.00; diffuse = 0.846), deterioration of renal function and quantitative proteinuria at the end of the follow-up period were noted. although qualitatively milder, the focal form of renal disease followed a course similar to that of the diffuse type.