Adults can be affected by autosomal dominant polycystic kidney disease, which is an inherited disorder that can cause renal failure and create the need for patients to undergo kidney dialysis. This disease is one of the most common inherited human disorders, making it important for scientists and physicians to understand what causes the diseases and how it progresses throughout a patient’s lifetime.
This disease is genetic and involves at least two genes. Most cases of the condition are related to defects in the PKD1 gene. Approximately 15% of cases are related to a genetic mutation of PKD2. In patients who have this condition as a result of a defect in PKD1, the disease is more severe and the mean age of end stage renal disease is 53 years. In patients with a defect in PKD2, the mean age for end stage renal disease is 74 years.
Diagnosing and Monitoring the Condition
ADPKD can be diagnosed and monitored using a combination of laboratory tests, imaging studies, and diagnostic procedures. Genetic testing can be performed to determine the likelihood of someone developing the disease. This involves taking blood samples from affected and unaffected family members and performing genetic analysis. Once the disease has been diagnosed, health care providers may order a complete blood count, serum chemistry profile, urine culture, and intact parathyroid hormone test to determine how far the disease has progressed and how it is affecting patients.
Several imaging studies can be helpful in diagnosing and monitoring adult polycystic kidney disease. Ultrasound can detect small cysts without the use of radiation or contrast material, making it one of the best options for imaging. The CT scan can detect smaller cysts, but exposes patients to radiation, so it is not frequently used in diagnosing or monitoring the disease. MRI is an excellent imaging tool, but is not frequently used due to the cost of the scan. MRI can be used to determine if a mass is a simple cyst or a renal cell carcinoma.
Effects on the Body
Adult polycystic kidney disease can have severe effects on the functioning of the kidneys and may also affect other parts of the body. The kidneys are affected by a reduction in urine-concentrating ability and the leakage of albumin. Later in life, patients may develop kidney failure. Hypertension is an early sign of this condition, affecting 50 to 75 percent of patients. Blood may appear in the urine as the result of damage to the kidneys caused by large cysts. Patients may also experience pain in the flank, abdomen, or back.
Patients who have normal renal function and do not have high blood pressure can be monitored yearly with laboratory testing and an ultrasound. Patients who develop hypertension need to be followed more closely and may be treated with ACE inhibitors or angiotensin II receptor antagonist blockers. Those who have developed renal impairment need to be followed the most closely and get immediate treatment for conditions such as elevated potassium and acidosis.
Treatment should focus on controlling abnormalities related to the disease, treating urinary tract infections, and controlling the pain associated with the disease. Surgical treatment may be necessary for large cysts, with fluid drainage resulting in pain relief for some patients. If kidney failure becomes advanced, dialysis or kidney transplant may be necessary.