PROTEINURIA

What is proteinuria?
Proteinuria—also called albuminuria or urine albumin—is a condition in which urine contains an abnormal amount of protein. Albumin is the main protein in the blood. Proteins are the building blocks for all body parts, including muscles, bones, hair, and nails. Proteins in the blood also perform a number of important functions. They protect the body from infection, help blood clot, and keep the right amount of fluid circulating throughout the body.

As blood passes through healthy kidneys, they filter out the waste products and leave in the things the body needs, like albumin and other proteins. Most proteins are too big to pass through the kidneys’ filters into the urine. However, proteins from the blood can leak into the urine when the filters of the kidney, called glomeruli, are damaged.

Proteinuria is a sign of chronic kidney disease (CKD), which can result from diabetes, high blood pressure, and diseases that cause inflammation in the kidneys. For this reason, testing for albumin in the urine is part of a routine medical assessment for everyone. Kidney disease is sometimes called renal disease. If CKD progresses, it can lead to end-stage renal disease (ESRD), when the kidneys fail completely. A person with ESRD must receive a kidney transplant or regular blood-cleansing treatments called dialysis.

CAUSES OF HEMATURIA

What are the causes of blood in urine?

The causes of gross and microscopic hematuria are similar and may result from bleeding anywhere along the urinary tract. One cannot readily distinguish between blood originating in the kidneys, ureters (the tubes that transport urine from the kidneys to the bladder), bladder, or urethra. Any degree of blood in the urine should be fully evaluated by a physician, even if it resolves spontaneously.

Infection of the urine, stemming either from the kidneys or bladder, is a common cause of microscopic hematuria. Kidney and bladder stones can cause irritation and abrasion of the urinary tract, leading to microscopic or gross hematuria. Trauma affecting any of the components of the urinary tract or the prostate can lead to bloody urine. Hematuria can also be associated with renal (or kidney) disease, as well as hematologic disorders involving the body's clotting system. Medications that increase the risk of bleeding, such as aspirin, warfarin (Coumadin), or clopidogrel (Plavix), may also lead to bloody urine. Lastly, cancer anywhere along the urinary tract can present with hematuria.

WHAT IS HEMATURIA?

What is blood in urine (hematuria)?

Hematuria, or blood in the urine, can be either gross (visible) or microscopic (as defined by more than three to five red blood cells per high power field when viewed under magnification). Gross hematuria can vary widely in appearance, from light pink to deep red with clots. Despite the quantity of blood in the urine being different, the types of conditions that can cause the problem are the same, and the workup or evaluation that is needed is identical.

People with gross hematuria usually present to their doctor with this as a primary complaint. Microscopic hematuria, on the other hand, is most commonly detected as part of a periodic checkup by a primary-care physician.