Diagnosis. When the urine is analysed the diagnosis becomes comparatively easy. Persistent albuminuria and hypertrophy of the kidneys during the early stages are significant indications. There can be little hesitation except in so far as pyelo-nephritis and hydro-nephrosis are concerned, but the conditions are distinguished by the character of the urine in the two latter cases, together with the condition of the pelvis of the kidney, and of the ureters.
Prognosis. The prognosis is grave, and Seuffert believes that recovery never occurs. This is also true, generally speaking, as regards all forms of chronic nephritis.
Treatment. As the disease must be regarded as incurable there is really no justification for treatment. Nevertheless, if for special reasons the owner wishes to keep the animals for a certain time, as in the case of a cow near its time of calving, recourse may be had to the internal treatment suggested in acute nephritis, viz., mucilaginous drinks, diuretic infusions, milk, bicarbonate of soda, stimulating applications to the loins, etc.
HYDRO-NEPHROSIS.
Hydro-nephrosis, i.e., retention of urine in the pelvis of the kidney and in the collecting and secreting tubules, is a somewhat common malady of the bovine species. It is usually confined to one kidney.
Fig. 228.—Hydro-nephrosis of the kidney.
Causation. Anything which obstructs the discharge of urine through the ureters may cause hydro-nephrosis. Thus, vesical tumours pressing on the orifices of the ureters, calculi which have become fixed in them, torsion or “kinking” of the ureters, may bring about hydro-nephrosis. The urine secreted by the kidney being unable to escape, accumulates in the pelvis of the kidney, in the ureter, and uriniferous tubules, producing dull colic, which escapes observation, or the exact cause of which is not discovered, because the second kidney vicariously acts for the one affected, and urination continues regularly. Secretion continuing in spite of the obstruction, that portion of the ureter above the obstructed point, together with the pelvis and the uriniferous tubules, gradually becomes dilated, until the whole mass of the kidney is hypertrophied.
The ureter sometimes becomes enlarged to the size of a man’s arm, the kidney double, treble, or quadruple its normal side: the interlobular divisions are lost, and each circumscribed lobule soon forms a cystic cavity varying in size. The pressure due to the accumulated urine causes the renal tissue, first the medullary substance and afterwards the peripheral zone, to undergo atrophy.
The kidney is represented by a vast cystic cavity, and the lobules by culs-de-sac; the cortical layer may become atrophied to such a degree as to form merely a fibrous sheath, the primary constituent elements of which are difficult to discover. From 20 to 40 pints of liquid may sometimes be found in the cystic kidney.