The natural history of nephrosis.

The suffix 'osis' signifies 'a diseased condition' and hence nephrosis means a diseased condition of the kidney (Webster'sNew International Dictionary). The term nephrosis was used by Muller (1905) to differentiate what he considered degenerative renal disease from other renal conditions to which the term nephritis was applied. He pointed out that hitherto the word nephrosis had been used to describe disorders of the renal pelvis (hydronephrosis, pyonephrosis), but considered that it would be more appropriate to use it for certain diseases of the kidney itself. Volhard and Fahr (1914) classified renal diseases into three groups: (1) Nephroses, in which degenerative lesions were present, with or without amyloidosis; (2) nephritides or inflammatory lesions; and (3) scleroses or arteriosclerotic diseases. Munk (1925) considered that the term nephrosis should be used for all degenerative renal lesions whether of albuminous, fatty, lipoid, necrotic, hyaline, amyloid or glycogen types. Evans (1932) restricted the term nephrosis to those types of Bright's disease which were associated with syphilis or amyloidosis. Allen (1952) used the term nephrosis for either chronic glomerular diseases of the kidney with oedema (lipoid nephrosis) or tubular diseases involving the proximal, distal or both parts of the renal tubules. Fishberg's (1954) conception of nephrosis is of a non-inflammatory disease of the nephron including necrotizing nephrosis, chronic lipoid nephrosis, diabetic glomerulosclerosis (the Kimmelstiel-Wilson syndrome), amyloidosis and toxaemia of pregnancy. By virtue of long usage the term 'pure' nephrosis has been applied to degenerative conditions of the renal tubules caused either by poisons, for example, mercury, lead, arsenic, or by general diseases, for example, syphilis and amyloidosis. These concepts of nephrosis are based largely upon histological evidence of damage to different parts of the nephron, but to many other writers nephrosis is a clinical rather than a histological entity, a view which has been well summarized by Kramer, Goldman and Cason (1952) in the following terms: