What is defined as the failure of kidneys to produce urine?

Anuria is defined as the failure of the kidneys to produce urine, typically characterized by a urine output of less than 100 milliliters in a 24-hour period. This condition can occur due to various acute or chronic factors affecting kidney function, such as severe dehydration, acute kidney injury, or certain obstructive disorders.

In contrast, oliguria refers to a decreased urine output, typically defined as less than 400 milliliters per day, meaning that while there is some urine production, it is significantly lower than normal levels. Polyuria, on the other hand, is characterized by excessive urine production, which may occur in conditions such as diabetes or certain kidney disorders. Lastly, the term non-oliguric is used to describe a situation where urine output is preserved (greater than 400 mL per day) despite renal impairment, further distinguishing it from anuria. Understanding these definitions helps clarify the severity and implications of kidney-related conditions.