Mesangiocapillary glomerulonephritis type III and idiopathic membranous glomerulopathy. Morphometric comparison of the deposits and glomerular basement membrane including clinico-morphological correlations.

Fifteen renal biopsy specimens from patients with idiopathic mesangiocapillary glomerulonephritis type III (MCGN-III) and fifteen from patients with primary membranous glomerulopathy (MGN) for whom both light and electron microscopy as well as immunofluorescence microscopy and full clinical data were available were examined quantitatively and compared with six normal controls. Morphometric investigations of electron micrographs were performed by means of a computer image analysis system to compare glomerular basement membrane (GBM) thickness and the electron-microscopic density of the deposits in MCGN-III and MGN as well as to study whether these parameters could correlate with the clinical data. The study revealed that GBM thickness and the electron-microscopic density of the deposits were significantly-increased in MGN in comparison with MCGN-III. It should be also noted that the degree of proteinuria was closely correlated with the density of the deposits in both MCGN-III and MGN groups. While the present morphometric analysis of glomerular ultrastructure has not yet elucidated the nature of hematuria in MCGN-III and MGN, our results suggest the location rather than the density of the deposits may play a role in the process.