Urine may become contaminated with blood from various sources. In all cases, however, this condition denotes broken blood-vessels, either as the result of disease or accident. As to the precise seat of the lesion, some sort of opinion may be formed by noting the manner in which the blood is discharged. When coming from the kidney it is uniformly mixed with the urine. If the hemorrhage is from the bladder the blood-stained portion of the urine will most frequently be the last passed in the act of micturition, its greater specific gravity causing the blood to sink to the lowest portion of the organ, and only to be expelled at the final muscular contraction of the viscus. When the source of blood arises from injury to the urethral canal, it is washed out with the first portion of fluid issuing from the bladder.
Some cases of bloody urine are caused by injuries, the result of external violence; others may be traced to the presence of calculi (stones) in the kidney or the bladder, and occasionally also in the urethral canal. Structural changes resulting from one or other of the various diseases affecting these organs are accountable for a small percentage of cases.
When hemorrhage is the result of the presence of stone in the bladder or urethral canal, the offending body must be removed by operation. If it arises in the course of disease of the kidney, cold cloths should be applied over the loins, and small doses of tannic acid, with dux vomica, administered two or three times a day. The patient will require to be kept perfectly quiet, and the bowels maintained in a state of activity by light bran diet and two or three tablespoonfuls of linseed-oil morning and evening. Enemas of cold water will also assist in keeping the bleeding in check.