Answer: The term uremia was first used in 1847 to describe the symptoms of kidney failure. Doctors of 150 years ago saw patients with reduced urine output, and thought that the urine was instead going into the blood - - uremia means, “contaminating the blood with urine.” We now know that this is false - patients with kidney failure do not have urine flowing into their blood. Nonetheless, the terms uremia or uremic poisoning have persisted, and now mean the symptoms that patients feel when they have kidney failure.

Patients with kidney failure often say to me, “I have no pain, no trouble urinating, no symptoms in my kidneys. Why do you say I have kidney disease?” When the kidneys stop working normally, the effects are widespread, affecting many of the body’s organs, and affecting the way millions of cells function. It is sometimes confusing to patients and to doctors that abnormalities of the heart, lungs, stomach and intestines, skin, blood, eyes, glands and brain really represent kidney disease. Thus, symptoms of uremic poisoning may come from many different places.

Before dialysis or kidney transplants were widely available treatments, patients with kidney failure had progressive uremic poisoning. These days, most patients have some early symptoms of uremia as their kidney function declines, but prompt dialysis treatments or transplantation avoids most symptoms. Here are the symptoms of uremic poisoning: 

The Brain and Nervous System

As kidney failure progresses, patients often become drowsy or sleepy. They may sleep more, and it may become difficult to arouse them from sleep. The ability to think clearly or accomplish mental tasks may become impaired, memory may become imprecise and personality can change. Some patients develop muscle cramps or restless legs. A strange or burning sensation of the legs or feet is called “peripheral neuropathy.” As the kidney failure becomes worse, patients can become disoriented or confused, develop slurred speech, suffer from seizures and eventually fall into a coma.

Stomach and Intestines

A common symptom is loss of appetite, leading to weight loss and malnutrition. Even if encouraged to eat more, patients with uremia often are unable to eat much, become depleted in proteins and develop muscle wasting. As the kidney failure worsens, they get nausea and vomiting. The gums may become inflamed and sores can develop in the angles of the mouth. The intestine can become inflamed; ulcers may develop causing internal bleeding, with blood appearing in the stool or in vomited material.

Heart

Uremia can cause inflammation of the heart muscle or the lining around the heart, leading to palpitations or shortness of breath with congestive heart failure. The doctor can sometimes diagnose these problems during the physical examination: the heart examination sometimes shows a “pericardial rub,” or the lung examination shows sounds of extra fluid accumulation. Hardening of the arteries (atherosclerosis) is accelerated in patients with uremia, leading to enlargement of the heart, and blockages of the arteries feeding the heart, predisposing patients to chest pain and heart attacks.

Lungs

The lungs may fill with fluid from poor heart function (congestive heart failure) causing shortness of breath or easy fatigability. In addition, the lungs may become inflamed and fluid may collect around the lungs (pleural effusion) causing a cough and shortness of breath. 

Skin

Uremia commonly causes itching, sometimes a very distressing and persistent symptom. The skin color may change, taking on a pale or yellow tinge. A rash is sometimes seen, with small bumps that are red and itchy. These symptoms come from deposits of calcium in the skin.

Bones, Calcium and Phosphorus Balance

As kidney failure progresses, the body’s calcium and phosphorus balance is affected, resulting in changes in the bones. Calcium may not be normally absorbed from food, and the parathyroid gland keeping the calcium balance may become overactive, resulting in bone structure changes. While these changes sometimes cause no symptoms at all, some patients experience pain in their bones. Bones can become thin (“osteomalacia”) or inflamed (“osteitis”), and may fracture easily. Cysts or non-cancerous tumors in the bone can develop. Abnormal deposits of calcium in the skin or in the eyes may cause redness and itching.

Blood

Anemia, a deficiency of red blood cells, often develops early in kidney disease and worsens as kidney failure develops. This may cause fatigue, inability to do usual activities, shortness of breath with even mild exertion and a pale skin color. This anemia may also be in part responsible for the enlargement of the heart and impaired heart function. These days, doctors can diagnose anemia early in the course of kidney disease, and can give iron supplements and injections with erythropoietin to correct these symptoms and complications. As kidney failure worsens, the function of white blood cells and lymphocytes, blood cells that fight infection, may become impaired. The ability of the blood to clot normally may become affected, causing easy bruising and a tendency to bleed easily.

Metabolism

Many other body functions are affected by uremia. Blood sugar may rise because the muscles become resistant to the effects of insulin. The symptoms of diabetes may occur - with increased thirst and weight loss. The balance of the body’s fats may be altered (hyperlipidemia), and thyroid gland hormone may be affected. The sex glands are affected: men may experience diminished sex drive and a decrease in the size of the testicles. Women may also have depressed sex drive, menstrual periods may be altered or may cease, bleeding between periods may occur and cysts of the ovaries may develop.

Patients who understand these many symptoms of uremia may work closely with their doctors to avoid or improve many of them. The prompt treatment of anemia, the appropriate medicines to avoid calcium, phosphorus and bone disease and adequate preparation for dialysis can prevent many of these symptoms, and reverse many others. In a new and welcomed atmosphere of “patient-centered care,” people with kidney disease can understand what to expect as kidney function declines, and can work with their healthcare team to stay healthy.     

Answer provided by Alan Kliger, MD, Clinical Professor of Medicine, Yale University School of Medicine, and Chairman, Department of Medicine Hospital of St. Raphael, New Haven, Connecticut. Dr. Kliger serves as Chairman of the Forum of ESRD Networks, and is a director for the ESRD Network of New England; on the steering committee for the NIH Chronic Kidney Disease Education Project; and is officer and member of the RPA Board of Directors and serves on its Quality Patient Care Committee.

The Dear Doctor column provides readers with an opportunity to submit renal related health questions to healthcare professionals who specialize in the area of concern. The answers are not to be construed as a diagnosis and therefore, altercations in current healthcare should not occur until the patient's physician is consulted.

This article originally appeared in aakpRENALIFE, January 2004 Volume 19 Number 4. 

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