Polycystic Kidney Disease
Polycysiic kidney disease is a hereditary disorder in which fluid-filled sacs, called renal cysts, form in the kidneys. About 50,000 American adults have the disorder, which is responsible for about 5 percent of chronic kidney failure in the United States.
There are two general types of this disease: The adult, or autosomal dominant form, is more common and less severe. It generally does not appear until early adulthood, and when kidney failure occurs, it is usually after age 50. The infantile, or autosomal recessive form, is relatively rare. It shows up at birth or shortly afterward and results in early kidney failure. A variation of the infantile form of this disease remains asymptomatic during the early years, and generally causes less severe renal impairment. However, it develops in association with a congenital liver disease that often proves fatal.
As they become increasingly filled with cysts, the kidneys may grow to three or four times their normal size. Early symptoms include flank pain, a mass that can be fell in the kidney area, blood and protein in the urine, recurrent bladder or kidney infections, and kidney stones. High blood pressure is common, and some patients develop anemia. Alongside this condition, cysts often form in other internal organs as well, especially the liver and, less commonly, the spleen, pancreas, lungs, ovaries, testes, thyroid, uterus, and bladder. A major danger of the disease is development of kidney cancer, which is far more common than in people with noncystic kidneys.
Diagnostic Studies and Procedures
A complete physical examination and blood and urine tests are standard. A definitive diagnosis of this disease is made with the additional help of X-rays, ultrasonography, CT scans, and other imaging studies that show the kidney cysts and enlargement.
Medical Treatments
Because there is no cure for polycystic kidneys, treatment is designed to help prevent or control its complications. Hypertension may be treated with one or more medications, and antibiotics may be prescribed for bladder and kidney infections. Kidney stones may be treated with medication or pulverized with sound waves that make them easier to pass through the urinary system.
Sometimes, large cysts are punctured surgically, especially if they are causing acute pain, bleeding, or urinary obstruction. In severe cases, one or both kidneys may be removed.
Chronic kidney failure, which occurs when more than 90 percent of kidney function has been lost, can be treated with dialysis or by transplanting a new kidney. If a transplant is feasible, the approach that has the greatest probability for success is to use a donor organ from a living relative who is a close genetic match with the patient. Otherwise, a genetically compatible kidney taken from a recently deceased person may be used.
Alternative Therapies
There are no alternative therapies for treating polycystic kidneys, but some are helpful in preventing complications.
Herbal Therapy. To treat bladder and kidney infections, herbalists recommend uva-ursi (bearberry) in capsules or dried and mixed with warm water (1 tablespoon of herb to 8 ounces of water), which may be used as an adjunct to antibiotics.
Nutrition Therapy. Some research has suggested that a low-protein diet can ease the workload on the kidneys. A registered dietitian should be consulted for assistance in planning such a diet. If ample citrus fruits and juices are included, they will help acidify the urine, which may inhibit bacterial growth and reduce the risk of bladder infections. Blueberry and cranberry juices also inhibit bacterial growth within the bladder.
Self-Treatment
Because polycystic kidneys are hereditary, there is nothing you can do to prevent the disease. However, you may want to seek genetic counseling before starting a family. Because pregnancy puts extra strain on the kidneys, a woman with polycystic disease may be advised to forego having children.
Anyone with polycystic kidney disease' must be especially cautious about using drugs, as there are many that affect the kidneys; do not take any medication, including over-the-counter painkillers, without checking first with a doctor.
In general, patients with polycystic kidneys should never restrict either water or salt intake, because this can lead to dehydration. It is important to drink adequate fluids -- at least 8 to 10 glasses of water or other nonalcoholic beverages a day -- and consume a moderate amount of salt, unless a doctor advises otherwise.
Moderate exercise is safe, but contact sports such as football should be avoided because a blow to the kidneys can cause severe bleeding and more damage.
Other Causes of Chronic Kidney Failure
Chronic kidney failure may also be caused by kidney diseases such as nephropathy and glomerulonephritis, as well as by diabetes, hypertension, lupus, and atherosclerosis.