As described by the Merck Manual and the Mayo Clinic, polycystic kidney disease is a hereditary disorder that results in multiple, various-sized and progressively enlarging benign cysts in both kidneys. Inheritance is most commonly autosomal dominant and affects approximately 1 in 1000 people. People with the disease can be asymptomatic. Those who become symptomatic usually do so by ages 30 to 50. Initial symptoms may include high blood pressure, flank pain and blood in the urine. End-stage disease may result in renal failure. Diagnosis is made by family history and imaging with ultrasound or CT scan. Treatment is palliative--directed at the resulting symptoms and complications.
High Blood Pressure
Due to the presence of multiple cysts altering the architecture of the kidneys, normal kidney monitoring of blood volume is disturbed and renal hormones are stimulated that cause vascular constriction in the body. This results in high blood pressure.
Decreased Kidney Function
Growing and multiplying cysts in the kidneys progressively replace renal tissue and interfere with normal kidney function, limiting clearance of wastes and toxins which then build up in the bloodstream. This leads to a condition known as uremia. Progressive uremia leading to end-stage renal failure is treated with dialysis or renal transplant.
Hepatic and Other Cysts
In conjunction with cyst formation in the kidney, similar benign cysts generally also occur in the liver and their incidence increases with age. Unlike renal cysts, the hepatic cysts usually don't interfere with liver function. Similar cysts can also appear in the pancreas and intestines. There's also an increased incidence of colonic diverticula and abdominal wall and inguinal hernias.
Cardiac Abnormalities
Disorders of the heart valves such as aortic regurgitation and mitral valve prolapse can occur in up to 25 percent of people with polycystic kidney disease. Aneurysms of the coronary arteries have also been reported.
Brain Aneurysms
Potentially the most serious complication of polycystic kidney disease is the presence of associated brain aneurysms--an abnormal dilatation of a brain blood vessel. Incidence of this condition also increases with age in people with polycystic kidney disease, reaching up to 10 percent in elderly people. Due to their weakened walls, brain aneurysms can acutely rupture, causing massive hemorrhage that may lead to death. The presence of associated high blood pressure from polycystic kidney disease increases the likelihood of aneurysm rupture, as does a prior family history of aneurysm rupture.
