CONGESTION, INFLAMMATION, AND SUPPURATION—BRIGHT'S DISEASE.
Congestion of the kidney implies overful ness of the blood-vessels of the organ. This, it is plain, may be either because a much larger quantity of blood than usual is streaming into the kidney by the arteries, in which case the congestion is said to be active, or because, the usual quantity passing in by the artery, it is hindered in its escape along the veins, in which case it is called passive. Active congestion may be the preliminary to fully developed inflam mation ; it may be the result of exposure to cold; it often is due to the irritant action of a poison circulating in the blood, such as that of scarlet fever, measles, or typhus, or the effect of the action of some medicine, Spanish fly, tur pentine, or cubebs. Thus irritation of the kid neys often occurs through the application of a fly-blister. The passive form arises when there is obstruction to the circulation, leading to accumulation of blood in the veins. Heart and lung diseases are frequent causes. Pressure on veins by a tumour will readily produce it, and thus in pregnant women the enlarged womb sometimes obstructs the flow of blood in the veins.
The symptoms are mainly connected with the urine, which may be increased in quantity and pale, while the patient complains of tender ness or some degree of heavy pain in the loins. Such symptoms would indicate active conges tion. Usually, however, the quantity of urine is diminished, is high-coloured, and contains albumin, and sometimes blood, and what are called tube casts. The method of detecting these is described on p. 407.
The treatment consists of rest in bed, hot applications over the loins or a warm bath, and a brisk dose of purgative medicine. But since the commonest cause of congestion is an obstruc tion to the circulation, its seat would require to be made out, and the treatment directed to aid its removal. That would imply an examination of heart and lungs, &c., which only a physician could properly perform.
Inflammation of the kidney (Nephritis. Greek, nep/ros, the kidney—Bright's Disease Albuminuria). There are various kinds of in flammation of the kidney dependent on the fact that the whole structure of the kidney is not at first attacked, the disease beginning at first only in the tubules (p. 393), or in the blood-vessels (p. 394), or in the fine connective tissue which acts as a framework for tubules and vessels ; though after it has begun in one of these it tends to pass to the others. Of
late years different names have been given in order to signify in what portion of the kidney structure the inflammation has begun. All the various kinds are included under the general. term Bright's Disease, because it was Dr. Richard Bright, of London, who first, in 1837, showed the relation between certain symptoms, namely, the presence of albumin in the urine and dropsy, and alterations in the structure of the kidney. One symptom is common to all the forms of the disease, that is, the presence in the urine, in greater or less quantity, of albumin, which, as has been noted on p. 396, is never present in healthy urine. Hence another general term is sometimes employed to include the various forms of the disease, a term which simply points to the main symptom—albumin in the urine,—the term albuminuria.
For the purposes of this work the simplest way of describing the various forms of inflam matory disease of the kidney will be to divide them into acute and chronic forms.
In Acute Bright's Disease it is the urinifer ous tubules (p. 393) that are specially attacked. They become altered, and the cells which line them are swollen and cloudy. The flow of blood te- the organ is excessive, so that it is congested. Fluid escapes from the vessels into the tubules, clotting there and so block ing the tubes, or blood may pass by rupture of the overloaded vessels. The cells tend to become fatty and to break down. The clotted material may be swept out of the tubes by the urine in the shape of casts of the tubes, as well as the diseased cells shed from the tubes, and blood, so that these all appear in the urine when passed, and may be detected by appropri ate means (see p. 404). The inflammation may so affect the kidneys that they are unable to discharge their function, urine ceases to be secreted, and the accumulation of waste matters in the blood causes death. The inflammation may cease before serious changes have occurred, and recovery then take place. It may gradu ally pass off, leaving blocked tubules, tubules stripped of their cells, blood-vessels thickened, &c., from which ultimate recovery may result so far as the patient's health is concerned, though the structure of the kidney has been permanently affected ; or the disease may become chronic.