Albiiiiiiiiitria. 455 



exudate, etc.. must offer a resistauce to the outflow of urine; and 

 any severe renal inflammations in which the epithehal cells be- 

 come degenerated must reduce or stop entirely the secretory 

 power of the organ. In the first group the urine is danmied 

 back and pressure atrophy of the renal parenchyma takes place, 

 the cortical portion continuing to secrete for a time and urine 

 being unable to escape ; and in the other type of cases the pas- 

 sages are open, but the original secretory disturbance determines 

 a diminished production and a pathological composition of the 

 urine. In case of unilateral disease such faults may be compen- 

 sated by the opposite organ which remains functionally capable, 

 which receives a larger proportion of the substance requiring ex- 

 cretion in the urine, functionates more freely and becomes hyper- 

 trophied. The secretion of urine nni«t decrease also in conditions 

 in which a diminished amount of blood flows into the kidneys as 

 the result of narrowing of their blood vessels, as from shrinkage 

 of the renal capillaries and atrophy of the glomeruli ( in chronic 

 interstitial nephritis), from thrombosis of the renal arteries, or 

 notably from lowering of blood pressure as in cardiac failure and 

 a number of the above mentioned conditions. In the same way 

 a reduction in the output of urine takes place when large quan- 

 tities of fluid escape from the body by other routes or where the 

 fluid is kept back in the tissues as in fevers, diarrhceas, or forma- 

 tion of fluid exudates and transudates in the body cavities. 



One of the most important pathological phenomena is the ex- 

 cretion of albumen with the urine, alhniuiunria. In normal con- 

 ditions, at least in states in which it is impossible to clearly dis- 

 tinguish between normal and pathological conditions, it is true 

 there is a very small quantity of the blood albumen passed 

 through the kidneys, so small tb.at it can only be recognized in 

 nurposefully concentrated urine and by special methods of de- 

 termination, as after fatigue from physical exertion (so-called 

 physiological and accidental albuminurias). When the amount 

 '^f albumen passed in the urine becomes sufllicient to be recog- 

 nized by the ordinary albumen reagents, there is reason to ap- 

 prehend the pathological disturbance of the renal function. This 

 may be of a quickly transitory nature, of no particular importance 

 and indistinguishable from the above mentioned non-pathogenic 

 symptomatic conditions; but as a rule it is an indication of some 

 lesion of the renal parenchyma. 



AH sorts of poisonous substances, both those of external 



