Healthy kidneys normally prevent significant amounts of protein from passing into urine. Damage to the kidney's filtering structures can allow protein to leak through.
Protein in the urine is called proteinuria and can be an important marker of kidney disease.
A urine test is needed to determine whether protein is actually present. Looking at urine appearance alone cannot provide a diagnosis.
4. Blood in the Urine
Blood in the urine, known medically as hematuria, should not be ignored.
Urine may appear pink, red, or brown when there is visible blood, although bleeding can also be microscopic and detected only through testing.
Possible causes include urinary tract infections, kidney stones, certain medications, prostate problems, kidney disease, and other conditions.
Blood in the urine does not automatically mean kidney failure or cancer, but it does warrant appropriate medical evaluation, particularly if it persists or occurs without an obvious explanation.
5. Persistent Fatigue or Weakness
Advanced kidney disease can contribute to significant fatigue.
One reason is that damaged kidneys may produce less erythropoietin, a hormone involved in stimulating red blood cell production. Reduced erythropoietin can contribute to anemia.
Anemia may cause:
Tiredness
Weakness
Reduced exercise tolerance
Shortness of breath with activity
Difficulty concentrating
Fatigue is extremely nonspecific, however. Poor sleep, stress, nutritional deficiencies, thyroid disorders, infections, anemia from other causes, and numerous other conditions can produce similar symptoms.