Polycystic Kidney Disease (PKD) Types, Causes And Treatment

Polycystic kidney disease is the most common inherited kidney disease where cysts or fluid-filled sacs develop in the kidneys, interfering with their ability to filter waste products. When these cysts grow, the kidneys become enlarged and lose their function and this is when polycystic kidney disease causes kidney failure.
 

What Are The Polycystic Kidney Disease Causes?

Polycystic kidney disease causes involve genetic alterations. It is usually a genetic disorder. A small percentage of cases do not involve genetic alterations and these are called acquired polycystic kidney disease. Acquired polycystic kidney disease occurs in patients undergoing dialysis treatment for other kidney problems and they eventually develop cysts in their kidneys.

Changes in PKHD1 gene causes autosomal resistant polycystic kidney disease and PKD1 and PKD2 gene changes result in ADPKD. Gene changes lead to formation of thousands of cysts that disrupt the normal functioning of the kidneys. The rate at which these cysts grow and inhibit kidney function depends on each individual.

Types Of Polycystic Kidney Disease

There are two major types of polycystic kidney disease. They are autosomal dominant polycystic kidney disease and autosomal recessive polycystic kidney disease. Both types may lead to kidney problems in the future.

1. Autosomal Dominant Polycystic Kidney Disease (ADPKD):

This is the most common form of polycystic kidney disease which develops cysts in the kidneys, liver, pancreas and other organs. There is a 50% chance of inheriting the gene causing this disease from your parents. These cysts are detectable between the age of 18-35 years.

Symptoms Of ADPKD:

You may not experience any symptoms in the earlier stages of ADPKD. The kidney cysts begin to form during childhood but they are hardly detectable and they grow slowly over the years. For most people, ADPKD could be diagnosed accidentally while taking X-rays or ultrasound for other conditions. The symptoms usually develop at around 30-40 years of age, which include:

• Frequent urination, sometimes at night.
• Pain at your back or side.
• High blood pressure
• Large or painful belly area
• Urinary tract infections
• Kidney stones
• Hernia
• Weak blood vessels in the brain
• Cysts in other body parts, particularly in the liver

2. Autosomal Recessive Polycystic Kidney Disease (ARPKD):

This is a rare form of the disease which is inherited from both the parents. This is a childhood disease that occurs soon after birth. People who have ARPKD gene, have a 25% chance of passing this gene to their children even if they do not have any kidney problems.

Symptoms Of Autosomal Recessive Polycystic Kidney Disease:

In ARPKD, the cysts develop in the early months of life or even before birth. Children and infants born with this problem have reduced kidney function that eventually results in end-stage kidney problems. You can observe some of the following symptoms in infants born with PKD:

• Facial deformities at birth
• Delayed or difficult childbirth 
• High blood pressure
• Heart and lung defects
• Swelling of the abdomen
• Blood in urine
• Anaemia
• Low birth weight
   

Can Polycystic Kidney Disease Be Cured?

There is no cure for polycystic kidney disease. The treatment aims to alleviate the symptoms and prevent further health complications. Before prescribing any treatment, your physician will evaluate your blood pressure and check if your urine samples show the presence of protein. 

Initial phases of treatment usually focus on lifestyle modification. Lifestyle modification involves avoiding food and medicines that are known to worsen your condition, paying attention to food and fluid intake and controlling blood pressure. Controlling blood pressure will help prevent heart complications in the future.

Your physician will recommend improving your fluid intake and get adequate bed rest. If your pain is due to infection, cyst, kidney stones or a possible tumour, it will be treated accordingly. If your pain is due to a nerve blockade, your physician will inject an anaesthetic medicine to numb the sensation. You shall take over-the counter medicines like paracetamol, to control your pain for the time being, but avoid using it on a long-term basis. 

Medications For PKD:

Medications used for treating polycystic kidney disease delays the disease from progressing. 

1. Tolvaptan: Vasopressin hormone is responsible for retaining water in our body. Tolvaptan acts against the vasopressin hormone and prevents the hormone from accumulating in the cells, which further releases fluid into the cysts. Thus, tolvaptan helps reduce the rate of cyst development and slows down the rate at which the kidneys enlarge due to cysts.

2. Blood pressure medications: Blood pressure medications work against substances that contract the blood vessels in the kidneys containing the cysts. These medications help preserve the kidney function

3. Antibiotic medications: Antibiotic medications prevent the cysts from causing and spreading infections. Some people, especially women with PKD experience urinary tract infections frequently. In such cases, antibiotic therapy is beneficial to prevent the infection from damaging the kidneys.

4. Octreotide: Studies conducted using Octreotide have shown that this medicine slows down the growth of cysts in the liver that resulted due to ADPKD.

5. Pravastatin: Pravastatin works to reduce the high cholesterol levels in children with polycystic kidney disease. However, further research on the effectiveness of this medicine on PKD is going on.

Surgical Approach To Treat PKD:

In some cases, the cysts grow larger and obstruct the nearby organs and tissues. In such cases, your physician might suggest a surgical procedure to drain your kidney cysts.

Implement Some Lifestyle Changes To Manage Your Symptoms:

Nutrition can play an important role in safeguarding your kidneys and delaying disease progression. Avoid foods and drinks containing caffeine, high protein and salt. Eat sufficient quantities of fruits and vegetables and do not consume foods that cause acidity. Exercise every day as much as you can and drink lots of water. Regularly monitor your blood pressure levels and ensure that it is maintained at 130/80 or lower.