Kidney failure
Kidney failure occurs when disease or injury impairs the kidneys’ ability to filter out body waste. When kidney function is impaired, wastes, toxins and excess fluid build up in the body, and necessary chemicals cannot be regulated properly.

• Acute kidney failure is a sudden and sometimes temporary loss of kidney function. It can be caused by infection, poisoning, injury, severe blood loss, burns or some medications.
• Chronic kidney failure is a slow and progressive loss of kidney function. It can be congenital, or it may be caused by diabetes, high blood pressure, recurring kidney infections, kidney stones or urinary blockage.
• End-stage kidney failure, also called end-stage renal disease or ESRD, is permanent kidney failure caused by severe damage that results in serious fluid and chemical imbalance.

Kidney cancer
Cancer can form in the tubes of the kidney that filter the blood (renal cell carcinoma) or in the tissue lining (transitional cell carcinoma). Other common kidney cancers are angiomyolipoma; oncocytoma, which are usually benign tumors; and Wilms tumor, which most often occurs in children below age five.

Diagnosis

Your doctor will usually begin by examining a urine sample. The presence of pus and bacteria in the specimen indicates a kidney infection. Urine can also be evaluated under a microscope for blood or crystals that may be evidence of a kidney stone. X-rays or ultrasound tests can then help determine the size of the stone and its location.

Albumin or other proteins in the urine may reveal diminished kidney function. Kidney failure is also diagnosed through lab tests that measure levels of certain waste products in the blood, especially blood urea nitrogen (BUN) and creatinine, which result from the breakdown of food proteins. Levels of these substances increase as kidney function decreases.

Kidney cancer is often discovered when a mass is found during a health screening. Imaging, such as abdominal ultrasound or CT scan, may also be used for diagnosis and to show the size and extent of the tumor. Other tests may be performed to find out if the cancer has spread.

Treatment

Kidney infections are most often treated with antibiotics and ingestion of fluids. If you are diagnosed with a kidney stone, you may be given pain medication and instructed to drink lots of water to help pass the stone. A stone too large to pass can be treated by lithotripsy, a non-invasive technique that uses ultrasonic shock waves to break the stone down into particles small enough to be eliminated in the urine. In a few cases, surgery may be required to remove the stone. Your doctor may also recommend dietary changes, increased fluid intake and possibly medications to help prevent additional stones from forming.

Kidney failure first requires treatment of any underlying disease or condition, such as diabetes or high blood pressure. Intravenous fluids and transfusions may be given, and surgery may be required if an obstruction such as an enlarged prostate or kidney stone is present. In cases of end-stage failure, dialysis or a kidney transplant are virtually the only options.

Radiation and chemotherapy, though commonly used for many types of cancer, are not as effective against kidney cancer. Surgery, therefore, is the primary treatment for most kidney cancers. During the surgery, your doctor may remove all or part of the kidney, depending on the size and type of tumor and the extent of the disease. Two other techniques are sometimes used for some patients with small kidney tumors: cryosurgery uses freezing and radiofrequency ablation (RFA) uses heat to destroy diseased tissue.

FAQ

What are some of the risk factors for kidney problems?

Primary risk factors for kidney failure are diabetes, high blood pressure, heart disease and family history. Age-related physical changes can also cause kidney function to decline. Kidney cancer occurs most often in people age 60 and older. Smoking, obesity and high blood pressure also increase the likelihood of kidney cancer.

What steps can I take to prevent kidney problems?

To prevent kidney infections:

• Drink plenty of liquids, especially water and cranberry juice
• Wear cotton underwear and loose clothing that does not trap heat and moisture
• Practice good bathroom hygiene

To prevent kidney stones:

• Drink plenty of liquids, especially water
• Eat a diet low in salt and animal protein
• If you have a history of kidney stones, ask your doctor about other dietary changes that may be helpful

To reduce risk of kidney failure:

• Manage conditions such as diabetes, heart disease or high blood pressure
• Have your blood and urine tested to detect kidney disease early
• Limit use of alcohol
• Avoid overuse of painkillers such as aspirin, ibuprofen and acetaminophen
• Avoid exposure to toxic substances such as heavy metals, fuels and solvents