Kidney patients routinely have their urine protein and blood pressure tested, as both elevated urine protein and high blood pressure independently destroy the glomeruli, or the filters in the kidney. Since this tissue does not regenerate, it is particularly important for kidney patients to take all possible steps to prevent further damage. While patients may not be able to eliminate the underlying disease, they often can slow down the progression of the disease by controlling these symptoms.
Testing
Positive tests for urine protein are fairly common, so doctors often repeat the test before assuming that something is wrong. In many instances, the protein can be caused by vigorous exercise or a bad cold. However, if the patient's urine repeatedly tests positive for the presence of protein, additional tests, such as an ultrasound or biopsy, may be necessary to determine if the patient has some form of kidney disease.
Treatment
The glomeruli in the kidney normally keep protein in the blood and prevent it from escaping into the urine. Proteins are relatively large molecules. Glomeruli are very delicate filters. If the patient has proteinuria, or high urine protein, for extended periods, the protein damages the glomeruli when it passes through the glomerular membrane.
Doctors treat proteinuria by prescribing angiotensin-converting enzyme inhibitors, better known as ACE inhibitors. These drugs lower the blood pressure in the glomeruli and prevent protein from spilling into the urine. In some instances, other drugs, such as prednisone, may be used.
Hypertension
High blood pressure is also known as hypertension. Kidney disease and hypertension go hand in hand because the kidneys are also involved in regulating blood pressure. The kidneys secrete a hormone called renin, which activates a system that increases the blood pressure when less blood is filtered. For kidney patients, this creates a vicious cycle because the increased blood pressure destroys more glomeruli, causing the kidneys to filter less blood, which in turn causes more renin to be secreted.
Blood Pressure Management
Treating kidney disease requires controlling blood pressure. In addition to a low-sodium diet, kidney patients often end up on four or five different blood pressure drugs to control renal hypertension.
There are many different pharmacological approaches to treating hypertension. In addition to ACE inhibitors, angiotensin receptor blockers, or ARBs, are often prescribed. Diuretics and beta blockers are other solutions to this problem.
References
- National Kidney Foundation: How Your Kidneys Work
- National Institute of Diabetes and Digestive and Kidney Diseases; High Blood Pressure and Kidney Disease; July 2008
- National Institute of Diabetes and Digestive and Kidney Diseases; Proteinuria; March 2009
- The Foundation for IgA Nephropathy: Hypertension and Chronic Kidney Disease
