Protein in urine is called proteinuria. This condition signifies an excess of proteins from the blood present in the urine. Several tests can detect proteinuria, including a urinalysis, which measures various substances in urine, and specific tests like the urine albumin-to-creatinine ratio (UACR) which quantifies albumin, a specific type of protein.
Understanding Proteinuria
Proteinuria isn't a disease itself, but rather a symptom indicating underlying kidney issues or other health problems. The amount of protein in the urine is crucial; having more than 150 milligrams per day is considered proteinuria. Different types of proteinuria exist, such as albuminuria (excess albumin in the urine), which can be caused by glomerular damage. Other causes include conditions like high blood pressure, diabetes, rheumatoid arthritis, and nephrotic syndrome (characterized by proteinuria, hypoalbuminemia—low blood albumin—and edema).
Causes of Proteinuria: Many factors contribute to proteinuria:
- Kidney Damage: Damage to the glomeruli (filtering units in the kidneys) is a frequent cause.
- High Blood Pressure: Hypertension can strain the kidneys.
- Diabetes: High blood sugar damages kidney function.
- Infections: Kidney or urinary tract infections can cause proteinuria.
- Autoimmune Diseases: Conditions like lupus and rheumatoid arthritis can affect the kidneys.
- Orthostatic Proteinuria: Protein appears in urine only when standing upright.
Diagnosing Proteinuria: A simple urine test (urinalysis) is commonly used for initial screening. More detailed tests, like the UACR or immunofixation electrophoresis (IFE, which detects specific proteins like Bence Jones proteins, indicative of multiple myeloma), may be necessary for diagnosis and to determine the underlying cause.
