What Happens

At first with chronic kidney disease, your kidneys are still able to regulate the balance of fluids, salts, and waste products in your body. But as kidney function decreases, you will start to have other problems, or complications. The worse your kidney function gets, the more complications you'll have and the more severe they will be.

When kidney function falls below a certain point, it is called kidney failure. Kidney failure has harmful effects throughout your body. It can cause serious heart, bone, and brain problems and make you feel very ill.

After you have kidney failure, either you will need to have dialysis or you will need a new kidney. Both choices have risks and benefits. To learn more about these choices, see Surgery and Other Treatment.

Complications of chronic kidney disease

• Anemia. You may feel weak, have pale skin, and feel tired, because the kidneys can't produce enough of the hormone (erythropoietin) needed to make new red blood cells.
• Electrolyte imbalance. When the kidneys can't filter out certain chemicals, such as potassium, phosphate, and acids, you may have an irregular heartbeat, muscle weakness, and other problems.
• Uremic syndrome. You may be tired, have nausea and vomiting, not have an appetite, or not be able to sleep when substances build up in your blood. The substances can be poisonous (toxic) if they reach high levels. This syndrome can affect many parts of your body, including the intestines, nerves, and heart.
• Heart disease. Chronic kidney disease speeds up hardening of the arteries (atherosclerosis) and increases the risk of stroke, heart attack, and heart failure. Heart disease is the most common cause of death in people with kidney failure.
• Bone disease (osteodystrophy). Abnormal levels of substances, such as calcium, phosphate, and vitamin D, can lead to bone disease.
• Fluid buildup (edema). As kidney function gets worse, fluids and salt build up in the body. When fluid builds up in the lungs (pulmonary edema), it can cause heart failure.