Prognostic pathologic markers in IgA nephropathy.

Previous studies have shown that the overall severity of the histologic grade and the extent of glomerular sclerosis are important pathologic markers of prognosis in IgA nephropathy. A previous analysis of the clinical and pathologic parameters in 74 patients at New York University Medical Center revealed that the renal survival (serum creatinine concentration of 2 mg/dL or less) was 100% in patients with mild proteinuria, 87% in those with moderate proteninuria, and 69% in those with heavy proteinuria. The incidence of segmental and global proliferation, glomerular sclerosis, tubulointerstitial damage, and vessel sclerosis increased with levels of proteinuria (P less than 0.01 to 0.05). A comparison of the morphologic parameters in 30 patients with similar initial serum creatinine concentrations (less than or equal to 2 mg/dL) but different outcomes demonstrates a greater incidence and severity of pathologic features, especially glomerular sclerosis in the "nonsurvival" than "survival" groups. Vessel sclerosis as quantitatively measured by a "point-count" technique correlates with the extent of glomerular sclerosis (r = 0.5192; P less than 0.001), suggesting a causal relationship or common basis.