5. Microscopical Examination.—This is the most reliable test for hmmaturia. '[he urine is treated in a centrifugal ap paratus and the sediment examined; even when the amount of blood is too small to alter the color of the urine the corpuscles of blood are easily detected by this method. Ordinarily the cor puscles are normal in appearance, but they do not accumulate in rolls; when the urine is dilute or alkaline, they are large, spherical, and almost colorless, commonly very transparent, whereas in concentrated urine their contour is ir regular and indented; in some cases the corpuscles are broken up (fragmented); in others, casts of renal tub uli formed by blood-corpuscles may be seen.
The admixture of blood to the urine may take place in the kidneys, the ure ters, the bladder, or the urethra; in order to ascertain the origin of the blood, it is necessary to subdivide the urine when voided into several parts. The first portion voided may contain blood of urethral origin, and the urine last voided show none whatever.
When the portion last obtained con tains much more blood than the first, the bladder probably is the seat of the bleeding. The endoscope will then gen erally allow the direct inspection of the bleeding-point of the mucous membrane of the bladder.
Too much value should not be placed upon so-called typical cell-elements in determining, by microscopical examina tion, the source of the haemorrhage. It is often impossible to distinguish be tween deep urethral and vaginal cells, between the latter and superficial vesical cells. Transitional cells are often mis leading, and the typical caudal cell from the renal pelvis is rarely seen. Charles Smith (Boston Med. and Slug: Jour., July, '93).
When the bleeding is caused by le sions of the ureters or of the calyces, cylindrical coagula or casts of the calyces may he found in the urine.
When the bleeding has taken place in the kidneys the blood is very intimately mixed with the urine; the corpuscles are often broken up or massed together, and casts of the renal tubes are commonly found.
Where the specific gravity of the urine is low the haemorrhage is apt to be re nal; where it is high, the lower urinary passages are usually the seat of origin.
Otis (Jour. Cut. and Genito.-Urin. Nov., '91).
If the bleeding is from the urethra it may ooze between the periods of micturi lion; if from the neck of the bladder, it is more particularly noticed at the end of micturition; if from the bladder, it is usually very abundant, persistent, and more likely to clot, and accompanied by bladder irritability; if from the kid ney, the blood is generally mixed with the urine, although, if the quantity is large, characteristic urethral clots may be found. F. R. Eccles (Brit. Med. Jour.,
June 5, '97).
The recognition of blood-casts in the urine forms the most conclusive proof of the renal origin of lnematuria. L. J. Harvey (Med. News, June 25, 'OS).
Haemorrhage due to renal calculus is usually small in amount and appears at more or less prolonged intervals; it is increased by movements of the body, and is appreciably diminished by rest in bed. Haemorrhage from a renal tumor is gen erally more profuse and less transient than from a calculus, and in some cases it is so copious as to cause marked anemia. Unlike the hmmaturia of renal calculus, that following tumors is more likely to occur during the night while the patient is in the recumbent posture. The presence of a persistent swelling in the renal region, associated with con siderable hcematuria, is of significance, and may be held as clearly indicating the presence of a neoplasm in the kidney. 11xmaturia from tuberculous disease is frequently absent for long intervals, is seldom so severe as from stone, and is not increased by exercise. In addition to the presence of tubercle bacilli, it has been noticed that the quantity of albumin is generally in excess of that accounted for by the blood, and in the later stage, when pus appears in con siderable quantity, the pus and blood are not so rapidly or so completely pre cipitated in the urine as in the presence of calculous pyelitis. Newman (Lancet, July 9, '98).
Eticlogy.—limaturia is more fre quently observed in men than in women or children. The blood in hmnaturia may come from the kidneys, their pelves. the ureters, the bladder, or from the ure thra.
Bleeding from the urethra may be caused by acute or chronic gonorrhoea, by traumatism (calculi, introduction of catheter), by polypoid excrescences, or malignant tumors. It has been observed as a result of venereal excess or as an accompaniment of the first coitus after a long period of abstinence.