In these latter cases the pyelo-nephritis assumes the acute form, and is accompanied not infrequently by cellulitis and abscess formation in the tissue around the kidney.
Symptoms. Pyelo-nephritis develops in one of two principal forms, the slow chronic form, which is the most frequent, or an acute or subacute form, much more rapid in its development.
The chronic form for a time escapes notice. There is no doubt that at first some general disturbance occurs, such as diminution of appetite, disturbed nutrition, unhealthy general appearance, staring of the coat, tightness of the hide, wasting, etc., but such symptoms are in no wise characteristic, being found in all grave diseases.
The signs only become really significant from the clinical standpoint when the urine appears modified in character, and such modification does not occur until the pelvis of the kidney and the kidneys themselves are already gravely diseased.
The urine is then turbid, of a brownish colour, and charged with sediment, filaments of mucin, pus corpuscles, and earthy phosphates. On analysis it is found to contain more or less albumen.
At a late stage it may even become glairy, blood-stained, or of the colour of blood, and when the pelvis or the calices of the kidney are ulcerated may, on standing, deposit considerable quantities of red blood corpuscles.
Fig. 230.—Pyelo-nephritis with hæmorrhagic pyo-nephrosis of one side. One ureter is dilated and blocked with a blood clot.
Exposed to the air, the urine rapidly assumes a brown tint and smells strongly of ammonia.
Percussion of the loins in the region of the kidneys causes pain, as does external palpation by the flank. On rectal examination at this period the ureters are found to be distended and hard, and they give the impression of rigid or bosselated fibrous cords, sometimes as large as a child’s arm. The corresponding kidney, often both kidneys, are enlarged, sometimes to double or treble their normal volume, and are painful on pressure and fluctuating, at least in the region of the pelvis. On vaginal examination the meatus urinarius is usually found to be inflamed, rough and turgid.