Progression of renal insufficiency often continues des-atubular glomerulus has a smaller volume if the tubulopite the removal of the aetiological factor responsible interstitial disease develops before adulthood, whereas for the renal disease. The pathogenesis of the progres-it is less reduced in size if the disconnection takes sion is poorly understood although it is well known place in an adult. The largest volumes are seen in the that quite different types of injury often lead to the glomeruli that are connected to normal proximal same structural changes. The final stage of the renal tubules, and these glomeruli often enlarge due to disease often shows the same histopathologic changes, compensatory hypertrophy. These hypertrophied ie interstitial fibrosis, tubular atrophy and glom-glomeruli also have the greatest number of glomerular erulosclerosis. capillaries [9]. In the remnant kidney model, the atubu-In order to investigate further the morphological lar glomerulus also has a much smaller volume than a changes in chronic renal disease, the author and others glomerulus connected to a normal proximal tubule [8]. have investigated a number of experimental models In experimental settings, a good correlation has been and human diseases with varying progression of renal found between the decrease in renal function and the insufficiency using advanced stereological, electron length (or volume) of proximal tubules, on the one microscopic and immunohistochemical methods. The hand, and the percentage of glomeruli that are constereological methods included serial sectioning of the nected to normal proximal tubules on the other hand. tissue in order to see whether or not atubular glomeruli This indicates that the atubular glomeruli (and glomerwere present and to estimate the glomerular volume. uli with atrophic tubules) do not contribute to glomer-An atubular glomerulus is a glomerulus that is notular filtration. connected to its proximal tubule (disconnected). In his In advanced cases of renal artery stenosis, immunoelegant investigation by microdissection of the kidneyhistochemical methods able to distinguish between in Bright’s disease, Oliver was the first to demon-different parts of the nephron reveal that more proxstrate the existence of both atubular glomeruli andimal than distale tubules have vanished. In the same aglomerular tubules [1]. kidneys, as many as 50% of glomeruli may be Various investigations on human and animal tissue atubular [5]. have demonstrated atubular glomeruli in many tubulo-Ultrastructural investigation of the atubular glomerinterstitial diseases, such as lithium and cisplatin ulus has not shown any marked changes. The mesangnephropathy, human chronic pyelonephritis, chronic ium is slightly increased and the basement membranes allograft rejection and also renal artery stenosis [2–7]. thickened, but the epithelial foot processes only show In diseases other than primary tubulointerstitial disminor variation in size [6]. Scanning electron microeases, such as diabetic nephropathy and experimental scopy may be used to see whether the glomerulus is renal ablation, a significant number of atubular glomatubular or not and to investigate the structure of the eruli have also been found [6, 8]. The percentage of glomerular tuft and the parietal epithelium. By these atubular glomeruli in advanced cases may reach> 35% means, a number of the atubular glomeruli were found (Table1). A large proportion of the non-atubular inside cystic dilated Bowman’s capsules [10]. glomeruli are connected to atrophic proximal tubules Much evidence points toward atubular glomerulus and only in a minority are they connected to a normal as an …