Quantitative changes of urine
One normally produces 500 - 2500 mL of urine per day. In case of pathology, the amount may be increased or decreased.
Polyuria refers to pathologically increased amount of urine (> 2500 mL/day) or > 50 mL per kg of bodyweight per hour. It's a relatively rare finding.
Oliguria refers to decreased amount of urine (100 - 500 mL/day) or < 20 mL/hour or < 0.5 mL per kg of bodyweight per hour.
Anuria refers to having < 100 mL of urine during a day.
Causes
- Polyuria
- Diabetes insipidus
- Diabetes mellitus
- Diuretics
- Primary polydipsia (psychogenic)
- Oliguria
- Due to acute kidney injury
- Prerenal causes
- Dehydration
- Heart failure
- Renal artery stenosis
- Intrarenal causes
- Acute tubular necrosis
- Acute or chronic glomerulonephritis
- Acute interstitial nephritis
- Postrenal causes
- Obstruction
- Anuria
- Generally same as for anuria, but more severe