PERINEPHRITIS. 41 



toms bear a strong similarity to those of acute interstitial nephritis. 

 A violent fever, which sometimes is ushered in by one or more rigors, 

 and by severe pain in the region of the kidney, which becomes intoler- 

 able whenever the adjacent muscles of the body contract, or are sub- 

 jected to any strain by movement of the body, is a symptom common 

 to both diseases. There is one important distinctive point between 

 the two; in pure uncomplicated perinephritis, there is no suppres- 

 sion of urine, nor does the urine contain either blood, albumen, or 

 pus. If the disease goes on so as to give rise to a large abscess, a tu- 

 mor appears in the renal region, which fluctuates with greater or less 

 distinctness. If the abscess break into the cavity of the abdomen, it 

 occasions an acute peritonitis, which speedily terminates in death. 

 Recovery may take place where the abscess discharges into the intes- 

 tine, or where it points externally, or is opened artificially. External 

 opening of the abscess generally occurs in the back, below the false 

 ribs, and is usually prepeded by an excessive aggravation of the pain 

 upon movement of the body, and by a more or less extensive oedema 

 of the skin over the region affected. In other cases the pus descends 

 along the psoas muscle, giving rise to a symptomatic abscess, which 

 usually makes its appearance below Poupart's ligament. 



TREATMENT. The most appropriate treatment of a recent case of 

 perinephritis is local blood-letting, and, in a later stage of the disease, 

 the systematic application of cataplasms and, the use of lukewarm 

 baths. Abscesses must be opened as soon as possible, according to 

 surgical rules, and should be kept open for a while. 



CHAPTEK VII. 



AMYLOID DEGENERATION' OP THE KIDNEY PARENCHYMATOTJS NE- 

 PHRITIS, WITH AMYLOID DEGENERATION. 



THE kidney, like the liver and the spleen, not unfrequently under- 

 goes a degeneration, by the deposit in the elements of its tissues of a 

 material whose reaction against iodine and sulphuric acid resembles 

 that of the cellulose of plants, but whose chemical constitution is more 

 like that of the protein substances. Amyloid degeneration of the kid- 

 ney takes place under conditions similar to those under which it oc- 

 curs in the liver and spleen, its causes being severe chronic disease, 

 such as syphilis, mercurial poisoning, rachitis, consumption of the 

 .ungs, and long-standing suppuration, such as occurs in caries and 

 necrosis. 



The degeneration probably always commences in the walls of the 

 blood-vessels, particularly in those of the glomeruli, to which it usually 



