THE URINARY ORGANS. 



629 



is also induced by various exogenous poisons, such as corrosive subli- 

 mate, carbolic acid, cantharides, and many others; it may occur with 

 extensive lesions of the skin and after exposure to cold. In the acute 

 nephritis following extensive burns, exposure to cold, etc., it is probable 

 that the poisonous products of abnormal body -cell metabolism are the 

 direct excitants. 



Bacteria may be eliminated from the body through the kidney some- 

 times without inducing lesions which are demonstrable with our present 

 technique. ' The following bacteria have been found by numerous ob- 

 servers in the kidney and in the urine, in acute diffuse nephritis: the 

 typhoid bacillus, pneumococcus, streptococcus and staphylococcus, the 

 colon bacillus, and others. The Plasmodium malarise may be present in 

 the kidney in large numbers. 2 To what extent the kidney lesions are due 

 to the presence of these organisms themselves and to what extent t o elimi- 

 nated toxins is not yet clear. 



Persistent and Advancing Lesions following 1 Acute Diffuse Nephritis. 



If we follow the alterations which the kidney in acute diffuse nephritis may un- 

 dergo, if resolution do not occur, but the process continues, we find that in each of the 



FIG. 390. DIFFUSE NEPHRITIS. 



Showing an advancing lesion following an acute type. Note the formation of a patch of dense fibrous tis- 

 sue, with thickening of the walls of the glomeruli and atrophy of the tubules. 



three structural units of the kidney, the glomeruli, the tubules, and the interstitial tissue 

 with the blood-vessels, important changes take place which often lead to slight or to 



'See Biedl and Kram, Arch. f. Exp. Path. u. Phar., Bd. xxxvii., p. 1, 1896, bibli- 

 ography; also v. Klecki. ibid., Bd. xxxix., p. 178, 1897; also Sittmann, Deut. Arch, t 

 klin. Med., Bd. liii., p. 328, 1894. See also references pages 163 and 624. 



'- For a study of malarial nephritis, see Thayer, Am. Jour. Med. Sciences, vol. cxvi., 

 p. 560, 1898. 



See for the study of a case of acute malarial nephritis with large numbers of para- 

 sites in the kidney, Ewing, Trans Assn. Am. Phys., vol. xvi., 1901. 



