A HISTOPATHOLOGICAL STUDY OF ESSENTIAL RENAL HEMATURIA

Abstract

Before making a histopathological study of essential renal hematuria, the author researched the structure of vessels about the renal calyces, which were obtained by injecting acryc resin into renal arteries. As a result, it was found that in the renal calyces there are the spiral arteries, which are branched off interlobar arteries.
The author made researches in the nine removed kidneys. They were all diagnosed essential renal hematuria, and had resistance to various conservative treatments. They were observed as serial sections, contained renal parenchyma, calyx and pelvis together in one section. And there were used such stains as Hematoxylin-Eosin, Masson's Trichrome, etc.
The findings are as follows. The bleeding region is the renal calyces in all cases. And moreover, the bleeding appeared at medulla, especially about cortico-medullary junction in five cases. At region of calcium plaque ablation in papillary apex, and the localized glomerular bleeding was accompanied at cortex in one case. In all cases, each kidney had hemorrhagic change in one or two calyces, although there was no special localization. And moreover, spiral artery showed the marked sclerotic change at those damaged calyces. On the other hand, remarkable congestions tendency was observed in the renal vessels everywhere; particularly calyx-wall showed the dilatation of capillaries, hemorrhagia per diapedesin, and early stage of granulation. As a more interesting view ie calyx-wall, having hard degeneration of the spiral artery, there were remarkably seen sclerosis of connective tissue and atrophic degeneration of the smooth muscle fibers. Consequently the calyx-wall gren thin, and at the same time, fissure of tissue (hemorrhagia per rhexin of capillaries) were observed at calyx-papilla angle and so on.
Judging from the above histological findings and literatures, the following is considered to be important.
One of etiological factors of essential hematuria exists in Locus minoris resistentiae. It is the region of tissue degeneration, which is due to disturbance of hemodynamics of the spiral artery, at the calyx-wall.
The author concludes that, when a factor of renal circulatory disturbance (particularly increasement of capillary blood pressure) joins in such Locus minoris resistentiae, at first hemorrhagic per diapedesin of capillaries is observed and then in the next stage hemorrhagia per rhexin of capillaries occurs, at the calyx-wall.