Proteinuria (Protein in the Urine): Symptoms & Signs

Medically Reviewed on 10/15/2021

Proteinuria refers to excess protein in the urine. While some amount of protein in the urine is normal, excessive amounts are a sign that the kidneys are not working properly due to a number of different reasons.

  • The main protein in the blood is albumin, which is also the main protein in the urine. For this reason, proteinuria is sometimes referred to as albuminuria.
  • Diabetes and hypertension (high blood pressure) are two chronic conditions that can cause kidney damage over time, leading to excess protein in the urine.
  • Acute (sudden onset) problems with the kidneys, like acute renal failure, also cause proteinuria.
  • Some conditions can transiently increase the amount of protein in the urine, including emotional stress, vigorous exercise, fever, or exposure to heat or cold extreme temperatures.

Other causes of proteinuria (protein in the urine)

  • Bacterial Infections
  • Chronic Renal Failure
  • Cystinosis
  • Fanconi Syndrome
  • Focal Segmental Glomerulonephritis
  • Goodpasture Syndrome
  • Hemoglobinuria
  • Idiopathic Membranous Glomerulonephritis
  • IgA Nephropathy
  • Interstitial Nephritis
  • Macroglobulinemia
  • Membranoproliferative Glomerulonephritis
  • Minimal Change Disease
  • Myoglobinuria
  • Nephrotic Syndrome
  • Renal Transplant Rejection
  • Uric Acid Nephropathy
  • Viral Infections
  • Wilson Disease

Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.

McPherson, Richard A., and Matthew R. Pincus. Henry's Clinical Diagnosis and Laboratory Medicine, 23rd Ed. China: Elsevier Saunders, 2016.