Changes of Urine Output in Chronic Kidney Disease

Kidney is responsible for producing urine, so when there is something goes wrong with kidney, urine output changes. Besides, apart from changes of urine output, chronic kidney disease patients also experience some other urine differences like foamy urine and blood urine. Here, in this article, we mainly introduce changes of urine output in chronic kidney disease.
Normal urine output for an adult
How much urine we should urinate a day? The normal range for an adult urinary output is between 400 to 2,000 mL of urine daily -- with a normal fluid intake of about 2 liters per day. Values for normal urinary output may vary slightly between laboratories. A urine output of 500 mL per day is generally considered adequate for normal function. Urinating too much or too less all are abnormal. Of course, exclude the conditions that you drink too much water at one time or drink less water for a long time.
Decrease of urine output in Chronic Kidney Disease
Some patients with kidney disease have decreased urine output, and this is because their kidneys can not filter as much blood as they should. In normal condition, blood flow through kidney and during this process, excess fluid are removed out of the body through kidney, so when kidneys are damaged, they will filter less blood and consequently, less fluids are removed out of the body as urine.
Why some kidney disease patients have normal urine output?
GFR is the indicator for filtration function of kidney. Usually, low GFR means kidneys filter less blood within limited time. Although the glomerular filtration rate (GFR) is very low in patients with end-stage kidney disease (ESKD), the urine output is variable, ranging from oliguria to normal or even above normal levels.And this is because besides GFR,tubular reabsorption also decides how much urine can be formed.
Blood flow through glomerular filtration membrane and during this process, some fluids are pushed into renal tubule where most of them are reabsorbed back to the body. In some cases, when kidneys are damaged, less blood are filtered by this filtration membrane, but if under such a condition, renal tubule can not function normally to reabsorb some of them back, all the fluids will flow out of the body as urine. Under such a condition, daily urine output may not decrease at all. (Any questions, please feel free to contact our online doctor)