Polycystic kidney disease - Symptoms, Causes, Types, Treatment

Causes of autosomal recessive polycystic kidney disease

The phenotypic manifestation of autosomal recessive polycystic kidney disease varies significantly. About 90% of ARPKD cases occur due to the mutation of PKHD1 gene on chromosome 6p12.

The regular function of tubular epithelium is dependent on the critical quantity of full-length protein released by this gene.

DAZ-interacting zinc finger protein 1-like (DZIP1L) has been connected to a few cases of ARPKD more recently, however it is extremely rare.

TSC1 and TSC2 mutations are seen in patients with tuberous sclerosis. Like PKD1, these genes are located on chromosome 16. Patients with tuberous sclerosis frequently present similarly to ARPKD and have an early onset of PKD.

Causes of autosomal dominant polycystic kidney disease

Two genes have been identified that are involved in mutations that cause ADPKD. Fifteen percent of ADPKD instances are caused by mutations in PKD2 gene on chromosome 4q21, while eighty-five percent are caused by mutations in PKD1 gene on chromosome 16p13.3.

In people with more variable polycystic liver disease, it is demonstrated that 1% people may diagnose with ADPKD due to mutations in GANAB gene.

Similar symptoms are expressed by mutations in the PKD1 and PKD2 genes. About half of people with PKD1 require renal replacement therapy by the time they are 60 years old. PKD2 mutations are more common in older people and are associated with a milder form of the disease than PKD1 mutations, with fewer renal cysts, late-onset hypertension, and less end-stage kidney disease (ESKD).

Polycystic kidney disease risk factors

• Family history: Polycystic kidney disease is a familial disease. It is a genetic condition that is inherited and is transferred from parents to offspring. The building blocks of heredity are genes. Each parent contributes a set of genes to the child at conception.
• Gender: The development of autosomal-dominant polycystic kidney disease (ADPKD) may be influenced by a person's gender. End-stage renal disease (ESRD) and renal function loss are more common in males with ADPKD than in women.
• Long-term dialysis: It is asserted that a type of polycystic kidney disease called acquired cystic kidney disease (ACKD) has been linked to long-term dialysis (PKD)
  

Polycystic kidney disease complications

Complications associated with autosomal recessive polycystic kidney disease may include:

• Azotemia (presence of high creatinine and waste products in the blood)
• Cholangitis (inflammation in the bile duct system)
• Congenital hepatic fibrosis (a rare genetic condition that impacts the kidneys and liver prior to birth)
• Gastrointestinal bleeding 
• Hypertension (high blood pressure)
• Increased risk for ascending cholangitis
• Large bilateral flank masses
• Liver failure and cirrhosis
• Poor absorption of fat-soluble vitamins
• Poor growth, feeding, and nutrition
• Progressive portal hypertension (increased blood pressure in the portal vein)
• Progressive kidney failure
• Renal osteopathy (a chronic renal disease consequence that affects bones)
• Respiratory distress brought on by pulmonary hypoplasia and constricted diaphragmatic movement as a result of the kidneys' immense enlargement 
• Splenomegaly (enlargement of spleen) may present in about 60% of patients
• Thrombocytopenia (low platelet count)

Complications that arise due to autosomal dominant polycystic kidney disease may include:

The most typical ADPKD complication is end-stage kidney disease, which necessitates dialysis or renal transplantation.

The most hazardous extra renal consequence of ADPKD is a ruptured cerebral aneurysm, which is four times more common in ADPKD patients than in the normal population.

Another recognized negative consequence of ADPKD is hepatic cysts, which are more common as people age. The frequency rises with age, with a 10%–20% prevalence up to the age of 30 and up to 50%–70% in people over 60.

Other complications that are frequently linked to ADPKD include:

• Abdominal wall or inguinal hernias
• Nephrolithiasis (kidney stones)
• Diverticular disease (medical condition that affects large intestine)
  

Polycystic kidney disease prevention

There is currently no known method for polycystic kidney disease prevention. On the other hand, kidney damage and other polycystic kidney disease issues brought on by high blood pressure might be slowed down by managing blood pressure at 120/80mmhg.

However, some preventive strategies are available to help manage symptoms, prevent or delay kidney function loss in patients with polycystic kidney disease, and help decrease the growth of cysts. They consist of:

• A healthy way of living that includes smoking cessation, exercising, controlling weight, and consuming less salt
• Consuming a large amount of plain water all day long
• Limiting the amount of caffeine in all drinks
• Consuming a lot of liquids as soon as blood in the urine is noticed
• Cautious blood pressure monitoring
  

Polycystic kidney disease diagnosis

Diagnosis of Autosomal dominant polycystic kidney disease

The most common methods used to detect autosomal dominant polycystic kidney disease include kidney ultrasonography, CT scans, and MRIs. As people become older, the cysts get bigger and more numerous. Therefore, the presence of even two kidney cysts in a 30-year-old patient with a family history of the condition is very suggestive. Once symptoms appear, a genetic test to identify mutations is typically conclusive but not always required.

Diagnosis of Autosomal recessive polycystic kidney disease

Since this is a condition that can be detected during pregnancy in mother’s womb, an ultrasound of the developing foetus may reveal enlarged kidneys. Since the condition leaves the liver scarred, liver imaging is also advised.

Polycystic kidney disease treatment

As the mutations causing polycystic kidney disease can no longer be corrected, this disease has no known treatment. The goals of treatment are to relieve symptoms and counter the complications. Medications may be used to treat urinary tract infections and to regulate hypertension. It is possible to enhance growth with growth hormone. When renal failure sets in, dialysis and transplantation become necessary. Pain may be managed using non-steroidal anti-inflammatory drugs (NSAIDS).

Difference between medullary cystic kidney disease (MCKD) and polycystic kidney disease (PKD)

Frequently Asked Questions (FAQs) on Polycystic kidney disease

What is bilateral polycystic kidney disease?

Bilateral polycystic kidney disease (BPKD) is a hereditary condition characterized by the formation of numerous cysts in both kidneys, resulting in organ enlargement and ultimately function loss.

What is polycystic kidney disease pathophysiology?

Mutations in polycystin 1 and polycystin 2 proteins can affect the function of renal cilia, which allow tubular cells to perceive flow rates. A prominent concept suggests that flow rate influences tubular cell proliferation and differentiation, and thus ciliary failure may result in cyst transformation.

Can polycystic kidneys be removed?

Polycystic kidneys should not be removed routinely prior to transplantation since nephrectomy (kidney removal) in ADPKD patients is associated with considerable morbidity and death.

What age does polycystic kidney start?

Polycystic kidney disease (PKD) symptoms typically appear between the ages of 30 and 40, but this can begin, even in childhood in case of an autosomal recessive poly cystic kidney disease. The condition is inherited as a dominant trait, thus children born to parents who carry the gene have a 50/50 chance of getting it.

Do polycystic kidney disease cause pain?

Yes, polycystic kidney disease (PKD) can induce pain, which occurs in around 60% of people with autosomal dominant PKD (ADPKD). The discomfort can be dull and continuous, or it can be temporary. It frequently arises in the side or back and can be felt as pressure on other organs or stretching of the cyst wall.

What causes death in polycystic kidney disease patients?

If polycystic kidney disease affects the brain, it might result in an aneurysm. An aneurysm is a bulging blood vessel that can rupture, causing a stroke or possibly death. If polycystic kidney disease affects the heart, the valves may become floppy, causing heart murmurs in some people.

Can polycystic kidneys burst?

Yes, there had been cases reported that the cysts in polycystic kidney disease (PKD) can burst, however this is uncommon, particularly in the presence of trauma. Rupture of an infected cyst might result in an abscess, sepsis, or death.