Possible causes of transient hematuria: 1, minor contusion of the kidney or bladder, such as a minor impact or collision of the waist or small abdomen, there is a transient contusion, at this time the patient may appear transient hematuria, after which the hematuria disappears or check the urinary routine visible microscopic hematuria, but the naked eye view of the urine color is normal. It is recommended to recheck urinary routine and urinary ultrasound after three days, if there is no organic damage, then drink more water and observe more, no special treatment is needed. 2. Urinary system infection, transient hematuria can occur in the acute infection period, and accompanied by serious urinary tract irritation symptoms, such as urinary frequency, urinary urgency, lumbago, etc., but after oral medication or drinking more water, the hematuria disappears, or the hematuria disappears after the inflammation is reduced, and the local mucosa self-repair. In this case, it is recommended to continue to review the urinary routine until the urinary routine is completely normalized and then stop taking oral anti-infective drugs. 3. Hematuria produced by the inflammation of the surrounding organs of the urinary system. For example, in patients with acute appendicitis, inflammation may invade the local ureter and lead to transient hematuria, often accompanied by symptoms of the primary disease, such as severe right lower abdominal pain. Regular monitoring of urinary routine and active treatment of the primary disease, such as control of appendicitis inflammation and removal of the appendix, are recommended, and hematuria may disappear.