The urinary changes usually begin abruptly, and the urine suddenly has the characteristics of one accompanying fever. The urine is usually much diminished in quantity, of high color, and high specific gravity-1025 to 1035. Relatively, the normal solids are increased; absolutely, normal or slightly diminished. The quantity of albumin depends upon the extent of the disturbance in the neighborhood of the area affected by the embolus. The sediment usually has the characteristics of a more or less severe active hyperemia or a circumscribed acute nephritis, which is in progress around the diseased area.

TUMORS OF THE KIDNEY.

These are benign or malignant. Of the benign tumors, the most common are the fibromata; lipomata, lymphadenomata, and angiomata are constantly met with. Adenomata may be congenital. Malignant growths-sarcoma or carcinoma-may be either primary or secondary. Sarcomata are the more common.

Tumors of the kidney grow rapidly and may attain a very large size-12 to 30 pounds. They are often soft, and hemorrhages frequently occur in them. In sarcomata invasion of the pelvis or of the renal vein is common. In almost all instances tumor is present. An increasing tumor in the anterior lumbar region, between the costal arch and the crest of the ilium, is always suggestive of renal tumor. The tumors are usually fixed, although they may be movable; they are frequently lobulated.

Prominent Symptoms.-Hematuria.-This may be the first indication. The blood is fluid or clotted; sometimes a blood-clot is passed having the appearance of a cast of the ureter.

Progressive Emaciation.-Loss of flesh is usually marked and advances rapidly.

Pain. This is generally present, and of a dull aching character, situated in the flank and radiating down the thigh. The pressure of the tumor often causes severe and alarming symptoms, such as edema of the feet and legs, ascites, disturbances of the stomach, various neuroses, the result of pressure on the large nerve-trunks,—and anemia. There is often frequent micturition, which may be so marked as to indicate a disease of the bladder when only the kidney is involved.

Character of the Urine.-Perhaps the most prominent feature of the urine is the presence of more or less bloodhematuria; occasionally, the amount of fresh blood is very large, but this is not true in every case. The urine usually shows evidence of a circumscribed inflammation or congestion of the kidney in the neighborhood of the new growth in other words, the urine presents the picture of a more or less severe active hyperemia of the kidney. Pus is generally absent in the sediment, save in advanced cases attended with decided destructive changes in the kidney or changes in the new growth itself. Under such circumstances the quantity of pus is comparatively small, considering the extent of the necrotic changes. Rarely, cancer elements can be recognized in the urinary sediment. sionally, the presence of a large number of epithelial cells with large and prominent nuclei and of various shapes is strongly suggestive of new growth, especially if the mucous membrane of the pelvis is involved or has become ulcerated. The presence in the sediment of organized elements, such as renal casts, renal cells, etc., is of little or no diagnostic value in renal cancer.

Осса

A diagnosis of renal cancer from the urine alone is only of the rarest occurrence, and then only in case particles of the morbid growth with a distinct alveolar structure are discovered in the sediment; but in malignant disease limited to the parenchyma of the kidney the appearance of portions of the growth in the sediment is practically unknown.

CYSTIC DISEASE OF THE KIDNEYS.

Cystic disease of the kidneys is probably the result, in most cases, of some obstruction to the outflow of urine through one or more renal tubules. Three varieties of cysts are met with:

1. Small cysts, seen especially in chronic interstitial nephritis, resulting from dilatation of obstructed tubules or Bowman's capsule.

2. Solitary cysts, ranging in size from a marble to an orange, or even larger, without evidences of other changes in the kidney.

3. Congenital cystic kidneys. In this condition the kidneys are represented by a conglomeration of cysts varying in size from a pea to a marble. The organs are greatly en

larged, and together may weigh from seven to ten pounds. In the fetus they may attain a size sufficient to impede labor. Little or no renal tissue may be noticeable, although on microscopic examination it is seen that a considerable amount remains in the interspaces.

The cystic fluid is usually clear, but it may be turbid, and sometimes reddish-brown or even black in color; occasionally, it is viscid. Specific gravity is usually low. Albumin, blood-corpuscles, and sometimes hematoidin crystals, leucocytes, cholesterin, triple phosphates, and fat globules are found in the contents. Urea and uric acid are present only in traces. The contents of one cyst may have an entirely different character from those of an adjacent cyst.

Character of the Urine.-In general the character of the urine is that of a chronic interstitial nephritis. In some instances the urine is not abnormal, especially in those cases in which there are no other changes in the kidney.

The diagnosis of cystic disease of the kidney can not be made with certainty from the urine alone. The condition, especially the congenital form, may exist unsuspected until found at the autopsy, death being the result of some other disease. Great enlargement of both kidneys, with hypertrophy of the left ventricle and increased arterial tension, would suggest cystic disease.

Operative interference is not justifiable.

It is important

to remember that the conglomerate cystic kidney is almost invariably bilateral. Osler cites an instance in which one kidney was removed and the patient died within twenty-four hours from cystic disease of the other kidney.

CHAPTER X.

DISEASES OF THE URINARY TRACT BELOW THE KIDNEY PROPER.

The diseases of the urinary tract below the kidney proper have received names according to their location and their duration. They are, for the most part, inflammatory in character, and may be either acute or chronic. In a consideration of the urine of all such diseases, the quantity of albumin, the total amount of urea, and the character of the sediment are of special importance for purposes of diagnosis.

PYELITIS.

This is an inflammation of the mucous membrane of the pelvis of the kidney; it may be either acute or chronic.

ACUTE PYELITIS.

An acute inflammation of the pelvis of the kidney may be either mild or severe, and local or general. Primary acute pyelitis is not of common occurrence, but is usually found to exist as an accompaniment or a complication of an acute disease of the kidney proper.

Causes. The disease is usually produced in one of three ways: (1) By the extension of an inflammatory process downward from the kidney; (2) by the upward extension of disease of the bladder; (3) by irritants confined within the pelvic cavity itself. An acute nephritis is usually accompanied by a more or less severe acute pyelitis (see p. 295)-in other words, the irritant that has set up the nephritis has also had its irritating influence on the mucous membrane of the pelvis by extension downward. Not infrequently an acute pyelitis (together with an acute nephritis) follows exposure to cold and wet, and it may be set up by the irritating action of the

toxines of certain acute infectious diseases, such as typhoid fever, scarlet fever, diphtheria, and septicemia. A gonorrheal infection of the lower urinary tract may, by extension, result in an acute pyelitis, and sometimes, later, an acute nephritis. When an acute pyelitis occurs without an accompanying acute nephritis or disease of the lower urinary passages, it is almost invariably due to the irritating action of crystalline elements or to a small concretion within the pelvic cavity. If due to a concretion, the inflammatory process may be circumscribed. Rarely, the pressure of a new growth, which is located outside of the urinary tract, on the pelvis of the kidney results in an acute pyelitis.

Prominent Symptoms.-There is usually more or less pain referred to the region of the affected kidney or kidneys, and it is often found radiating along the course of the ureter toward the groin. There is frequently some fever, although, as a rule, the temperature is not high. The disease may, however, be ushered in by a chill or a succession of rigors followed by a high temperature for a day or two. Hematuria is an early symptom, and usually continues for several days. The patient may suffer from renal colic, caused by the marked irritation of crystalline elements or by a calculus or blood-clot obstructing the outflow of urine through the ureter. Rarely, a pyonephrosis results from obstruction in the ureter. Micturition is more frequent than normal. The symptoms of an accompanying acute nephritis or a cystitis are often sufficiently prominent to entirely obscure those that are referable to the pelvis itself.

Character of the Urine.-The urine of a simple acute pyelitis, without much involvement of the kidney proper, usually has the characteristics of a fever urine.

Quantity. Considerably diminished-i. e., from 400 to 800 or 1000 c.c.

Color. High, and frequently smoky, sometimes a bloodred color, depending upon the amount and character of the blood present.

Specific Gravity. This is generally higher than normal -1025 to 1030, or as high as 1035.

Normal Solids.-Absolutely, diminished; relatively, increased.

Albumin. The quantity of albumin is variable, but in a general way corresponds to the amount of blood and pus present. As a rule, the quantity of albumin is chiefly rela