What is Polycystic Kidney Disease?
Polycystic kidney disease (PKD) is a condition that affects the kidneys. The disease is caused by a mutation, which leads to uncontrollable growth of fluid-filled sacs called "cysts" in the kidneys. It is the most common inherited kidney disease.
The cysts cause the kidneys to get bigger than normal. The cysts can also keep the kidneys from working normally. This can lead to problems, such as high blood pressure, kidney infections, and kidney failure. Kidney failure is when the kidneys stop working completely. Besides kidney problems, PKD can cause problems in other parts of the body.
The condition has 2 major forms:
- Autosomal dominant polycystic kidney disease (ADPKD), which affects 50% of offspring of the affected parent. The disease usually presents in the early 20s with observation of numerous cysts in the kidney in ultrasound. ADPKD leads to End Stage Kidney Disease (ESKD), requiring dialysis commonly in the fourth and fifth decade of life. It is worth noting that although ADPKD is known as a kidney disease, it is in fact a multisystem disease that affects the liver (most common extra-renal organ), brain and heart.
Autosomal Recessive Polycystic Kidney Disease is another form of the disease, which is much less prevalent, and it starts in early childhood and leads to ESRD very early in life.
- Known complications of ADPKD include high blood pressure, infection of the cysts, presence of blood and protein in the urine, and cyst rupture (which can present with intense pain). The manifestation of the disease in other organs can include enlargement of the liver, abnormalities in the heart valves, and findings of thinning and ballooning of the vessels in the brain, known as aneurysms. For all of the above-mentioned reasons, management of ADPKD requires a multidisciplinary expert team.
- ADPKD is the third most common reason for the patients to end up on dialysis in the USA. Over 600,000 patients in the USA suffer from ADPKD, and about 10,000 patients start dialysis every year because of the disease.
- Even though there is no approved treatment for the condition in the USA, there has been a lot of advances in our knowledge of the disease. Thanks to many important studies in the recent decades, these findings have helped us identify factors that can slow down the progression of the disease. Moreover, tireless efforts are being done to find a treatment.