Oliguria: Causes and Effects of Decreased Urine Output

5. Renal Failure

Renal failure also leads to oliguria because of loss of kidney function but in a different way than pre-renal kidney failure. In these cases, the damage occurs in the kidney itself. Many factors can cause renal damage, including blood clots in and around the kidneys, lupus, infection, toxins, medications, and scleroderma. Prolonged loss of blood flow (more than four hours) from pre-renal causes can also damage the kidneys.