If you are diagnosed with renal disease--commonly called kidney disease--it is important to understand all the possible symptoms that can occur. Although you may never experience the majority of these symptoms, most patients do experience some, in varying degrees. Eventually, you will get a good sense of which symptoms constitute a true emergency requiring immediate attention, and which can wait until your next visit to the nephrologist.

Hematuria

Some patients experience hematuria, which is the medical name for blood in the urine. If the blood is not visible to the naked eye, the condition is called microhematuria. If the blood is visible, it is called frank hematuria. Although this symptom is relatively common, a large number of those with kidney disease never experience it.

Proteinuria

In varying degrees, proteinuria is universal among renal disease patients. Proteinuria refers to abnormally high levels of protein in the urine. If your urine protein is only mildly elevated, your doctor may opt not to treat this symptom. However, nephrotic-range proteinuria is usually treated because it is believed that very high urine protein accelerates renal decline.

Cholesterol

Elevated cholesterol goes hand-in-hand with proteinuria. Fortunately, high cholesterol levels often decline when the elevated protein level goes away. Most studies on renal disease are consistent with the article published by Dr. Taha Keilani in the "Annals of Internal Medicine" whereby Keilani illustrates that if high urine protein is successfully treated with an ACE inhibitor, problems with cholesterol tend to abate as well.

Hypertension

Hypertension is often one of the very first symptoms of renal disease. This was first recognized by Richard Bright, a physician who practiced in the first half of the 19th century, and observed the changes of hypertension on the cardiovascular system in patients with chronic renal disease. As kidneys become progressively scarred, they sense less blood flow, and secrete angiotensin to constrict the blood vessels. A vicious cycle ensues because high blood pressure causes the glomeruli to blow out, which in turn causes more scarring, further reducing blood flow, and increasing the output of angiotensin. Kidney patients often take four or five medications to control hypertension.

Flank Pain

If you experience a dull ache in your lower back, you're in good company; this symptom is fairly common as well. If you are having sharp, stabbing or very severe pain, call your doctor immediately because such pain is not consistent with flank pain.

Anemia

The kidneys secrete a hormone called erythropoietin (EPO). EPO is responsible for the maturation of red blood cells. Immature red blood cells are called reticulocytes. Reticulocytes are not capable of binding oxygen. As kidneys become progressively scarred, they lose the ability to secrete this hormone. Consequently, you may end up with a very high "ret count" and a low "RBC" count. This type of anemia is very common in patients with advanced kidney disease. Fortunately, it's very treatable with injections of EPO.

Elevated Phosphorus

Itchy skin is also common among patients with advanced kidney disease. High levels of phosphorus can cause itchy skin. Normally, the kidneys filter out phosphorus, but when they become scarred, they lose this ability. Itching can be controlled by phosphorus binders and by eliminating high phosphorus foods such as cheese.

Elevated Potassium

Elevated potassium is a silent, deadly symptom that occurs in late stage kidney disease. Just as the kidneys lose the ability to filter phosphorus from the blood, they also lose the ability to filter potassium. Unfortunately, many patients are unaware this is happening until cardiac symptoms arise. Your doctor will let you know if you need to watch your potassium levels.

Nausea

As some patients approach end stage disease, they often find that they experience frequent, low-level nausea. Many find that by avoiding high protein foods they can minimize this, which in turn fosters the very real, malnutrition, common to many patients who are on the edge of renal failure.

Gout

Gout also can be a problem as renal failure approaches. Just as very scarred kidneys cannot filter potassium and phosphorus, they also lose the ability to filter purines. Dr. Mark Fahlen reminds us that as recently as the 1960’s, the association between gout and kidney disease used to be called "gouty nephropathy." Although gout can be excruciatingly painful, it can be controlled by a low purine diet and prophylactic medicine.