[Morphometric studies on numerical area density of glomerular cells (nuclear section) in the pathogenetic evaluation of minimal glomerular abnormalities].

Minor glomerular abnormalities (MGA) with hypercellularity (according to the WHO-nomenclature) are one of the most frequent glomerular lesions. Minimal proliferative changes in the glomerular structure can be proven only with the aid of morphometric methods. Morphometric glomerular studies were carried out in MGA with hypercellularity and with rare or minor deposits of immunoglobulins and/or complement (C3) or without deposits. Clinical symptomatology was variable (minimal to mild proteinuria, massive proteinuria, haematuria or haematuria with proteinuria). The groups examined were divided as follows: MGA without deposits and with minimal (mild) proteinuria. MGA with minor deposits and with minimal (mild) proteinuria. These two groups were statistically compared with: normal glomerular structure (after Wehner 1974); MGA with massive proteinuria or nephrotic syndrome (includes the minimal changes with nephrotic syndrome), which showed minor deposits of complement; diffuse mesangial proliferative glomerulonephritis (IgA-nephritis). The glomerular cell density, i.e. the total number of glomerular cells, averaged 3.48 cells/1,000 micron 2 in the first group and 4.26 cells/1,000 micron 2 in the second group. In normal renal corpuscles the average was 2.30 cells/1,000 micron 2. The first group has an average of 51% and the second group has an average of 84% higher cell density than normal renal corpuscles. The cell density in diffuse mesangial proliferative glomerulonephritis (IgA-nephritis) is increased by 160% compared with the norm. The first group was not statistically different in cell density from MGA with high proteinuria. We conclude, that MGA with hypercellularity and minimal to mild proteinuria represents a minimal mesangial proliferative glomerulonephritis.