M.D. Chapter XII Disease of the Urinary Tract Small or larger hemorrhages in the kidney capsule are frequent, but extensive extravasations are rare. Minute hemorrhages on the renal surfaces are common. In the kidney substance hemorrhages are most commonly found at the apex of the pyramids and in the medulla. Besides this zone of predilection there is another at the junction of the cortex and the medulla. Hemorrhages occur more often between the urinary tubules than in them.
Hemorrhages are usually present also in the same regions.
Bile pigment is precipitated in the kidney in the same areas in which there is a predilection for hemorrhage. That cylindruria and albiminuria may be present without gross demonstrable pathological change was mentioned before. The transition from physiological to pathological albuminuria is not abrupt and the instance of severe albuminuria is infrequent. Observations have been so few in the cases of nephritis in newly born prematures that an exact clinical picture has not been established. Quite frequently one finds parenchymatous or fatty degeneration of the kidneys following toxic or infectious conditions.