[Primary nephropathy due to mesangial deposits of IgA (Berger's disease)]

We describe findings in 188 patients with Berger's disease, the most frequent primary glomerulopathy in our renal biopsy material (25%). Diagnosis was made by finding IgA and dense mesangial deposits with immunofluorescence and electronmicroscopy, respectively. Patient's age ranged from 3 to 64 years (mean 27), 72 were females. Five degrees of the disease were recognized: I, minimal changes, 29 patients (15%); II, minor lesions, 37 (20%); III, focal and segmental lesions, 92 (49%); IV, diffuse proliferation of mesangial cells and/or glomerulo-capsular adhesions, 22 (12%), and V, diffuse sclerosing glomerulonephritis, 8 (4%). Clinical findings at the time of renal biopsy included isolated hematuria in 61%, nephrotic syndrome or proteinuria 11%, hypertension 16%, chronic renal failure 7%, acute renal failure or nephritic syndrome 3% and rapidly progressive glomerulonephritis 2%. Berger's disease was found in 10 clinically healthy donors (13% of living-related donors). Progression of lesions was shown by serial biopsy in 12 patients. Progressive Berger's disease was demonstrated in 5 transplanted patients, requiring dialysis in one. Thus, Berger's disease leads to varying degrees of renal damage, severe extramembranous nephropathy and crescentic glomerulopathy being less frequent.