The kidneys are two organs located in the upper and posterior part of the abdomen. 
The kidneys filter waste and fluid from the blood to form urine. 
Polycystic kidney disease (PAD) is a disease in which numerous benign cysts grow within the kidneys.

These cysts are small sacs filled with liquids . 
They are found in both kidneys, but may appear in one kidney before another. 
The cysts are of various sizes and grow when the fluid accumulates inside.

When the cysts grow, it increases the weight and size of the kidneys, up to 4 times the normal size. 
Do not confuse this disease with a single cyst that can form in healthy kidneys, polycystic kidney disease is the replacement of functional renal tissue with cysts.

Pathophysiology
The formation of cysts is caused by tubular cell proliferation, fluid secretion and changes in the extracellular matrix of the kidney. 
Gene mutations cause an anomaly in:

  1. Cell membrane proteins,
  2. Transport channels in the cell membrane.

The consequences are:

  1. Decrease of calcium inside cells. Calcium entering cells inhibits (blocks) cell proliferation.
  2. The level of vasopressin increases .

Due to these abnormalities, in the cell there is an increase in the production of cAMP (cyclic adenosine monophosphate) causing:

  1. Cell proliferation,
  2. Fluid secretion.

This is the mechanism that leads to the formation and growth of cysts in the kidney.

 


Types of Polycystic Kidney Disease

There are two main types of DRP: genetic and non-hereditary transmission. 
Polycystic kidney disease of genetic transmission is divided into:

  1. Autosomal dominant DRP
    It is a hereditary form of the disease, about 90% of cases of PRD are of this type. ‘Autosomal dominant’ means that if a parent is sick there is a 50% chance that the baby has DRP. 
    Many people with autosomal dominant PRD live for several decades without developing symptoms. 
    For this reason, DRP is called “adult polycystic kidney disease”. However, in some cases, cysts are formed in children and grow rapidly causing symptoms in childhood.
  2. Autosomal recessive DRP
    This is also a type of hereditary disease, but it rarely occurs. 
    That way, the child can have the disease even if the parents are healthy. This occurs when both parents have the recessive allele (in other words they are both “carrier of disease”). 
    The child becomes ill if he inherits the two  recessive alleles. 
    There are four types of autosomal recessive polycystic kidney disease:

    1. The perinatal form is present at birth.
    2. The neonatal form occurs in the first month of life.
    3. The child’s shape develops when the child is 3-12 months old.
    4. The juvenile form occurs after the child is 1 year old.

Polycystic kidney disease is also called acquired renal cystic disease (DRCA).
It is linked to chronic kidney problems that occur primarily in people with kidney failure and on dialysis for a long time. Therefore, DRCA occurs in the elderly. This type is not inherited because it is caused by a genetic mutation.

The polycystic kidney can be confused with the multicystic kidney, but they are two different things, the differences are:

The multicystic kidney (or multicystic dysplastic kidney):

  1. It is characterized by the presence of multiple and non-communicating cysts, of variable size
  2. It affects only one (one-sided) kidney.
  3. It causes the formation of cysts  in the kidneys and the urethra is obstructed.
  4. At birth it is asymptomatic, usually not a genetic disease, unlike polycystic kidney disease.
  5. It can be diagnosed with  fetal ultrasound , but for confirmation it serves the static renal scintigraphy.

Usually this disease regresses on its own (60% of cases) and no treatment is necessary, but in rare cases the kidney becomes very large or causes an important arterial hypertension and therefore must be removed.

 

Causes of Polycystic Kidney Disease

The cause of polycystic kidney disease is hereditary because it is caused by a genetic defect. 
There are 2 different forms of mutations that can cause disease. 
Accordingly, polycystic kidney disease is classified into 2 different types:

  • The most common autosomal dominant polycystic kidney disease(ADPKD) is cysts developed in the age group between 30 and 40 years. 
    Even if only one parent has the gene for ADPKD, there is a high probability of transmitting the disease to the baby.
  • The disease polycystic kidney autosomal recessive  (ARPKD) develops soon after birth. 
    This disease is transmitted to the child only if both parents are sick.

 

Symptoms of Polycystic Kidney Disease

Some of the common signs and symptoms include:

Some people may feel only mild symptoms, while others may disrupt the normal functioning of the kidneys.

 

Complications of the polycystic kidney

Complications associated with polycystic kidney disease include:

  1. Hypertension
    The high pressure is a common complication.
  2. Loss of renal function
    Almost half of patients develop renal failure at age 60. 
    This disorder can cause the accumulation of toxins and a disease called uremia.
  3. Growth of cysts in the liver . The likelihood of developing hepatic cysts for a person with polycystic kidney disease increases with age.
  4. Cerebral aneurysm
    People with polycystic kidney disease have an increased risk of aneurysm in the blood vessels of the brain.
  5. Heart valve abnormalities
    Approximately 1 in 4 adults affected by polycystic kidney disease develops mitral valve prolapse . When this happens, the valve does not close properly and allow the blood to flow back.
  6. Problems in the colon
    The patient may develop diverticula (strobiles) on the wall of the colon.
  7. Chronic Pain
    Generally, those who suffer from polycystic kidney experience back pain . Pain may be associated with a urinary tract infection, kidney stones , or tumors .

 


Diagnosis of Polycystic Kidney Disease

There are several diagnostic methods for detecting the size and number of renal cysts or for assessing the amount of healthy kidney tissue.

Since this disease is asymptomatic in many cases it goes unnoticed for many years. 
People with severe symptoms should go to the nephrologist for a diagnosis. 
In addition to the physical examination, some laboratory tests, such as blood and urine tests , ultrasonography and computed tomography are necessary for the correct diagnosis of the disease.

Ultrasound
The ultrasound is a diagnostic test in which a similar device with a wand (called a transducer) is placed in the patient’s body. 
The examination is also performed during pregnancy (ultrasonography of the fetus). 
This will emit inaudible sound waves that are reflected back to the transducer. 
The computer translates the reflected sound waves into images of the kidneys.

Computed Tomography
The patient lies on a movable bed and is led on a donut-shaped device that launches very thin bundles of x-rays through the body. The doctor is able to see the images of the kidneys in cross-section.

Magnetic resonance imaging (MRI)
When the patient is inside a large cylinder, magnetic fields and magnetic resonanceradio waves  generate an overview of the kidneys in cross-section.

The static renal scintigraphy is indicated:

  • To check the renal parenchyma,
  • Evaluate if the kidney has functioning tubules. Since the functioning of these tubules is reduced, the contrast medium is not sufficiently fixed.

Multicystic kidney – renal scintigraphy

It is possible to perform a genetic test to see if the parents can have a child with a polycystic kidney. 
However, the usefulness of this test is limited because there is no treatment to prevent or cure the polycystic kidney.

 


Treatment for Polycystic Kidney Disease

There is no treatment that can cure kidney disease. 
Therefore, doctors try to treat the patient’s symptoms.

First the doctor lowers blood pressure with medications . 
This is because reducing the pressure can reduce kidney damage. 
Patients should follow a diet that includes foods low in fat and sodium.

Among the recommended drugs for polycystic kidney disease is an anti-rejection called Sirolimus (inhibitor of mTOR, ie inhibitors of mammalian target of rapamycin) that appears to block the growth of cysts . 
Everolymus and somatostatin are some similar experimental drugs, which demonstrated a slight reduction of kidney volume in preliminary studies.

The chronic back pain and abdominal sides can be reduced with the help of painkillers over the counter. 
It is not recommended to treat this type of pain with over-the-counter painkillers.

The blood in the urine can be controlled by drinking more water and resting properly. 
Dilution of the urine can prevent the formation of clots in the urinary tract.

Kidney or bladder infections are treated with antibiotic tablets .

The doctor rarely opts for surgery that is performed in laparoscopy. 
This is only recommended in cases where the cysts have grown in size and cause severe pain or other health complications. 
During the operation drain the fluid from the cysts.

Renal insufficiency . If the kidneys lose the ability to remove waste and fluids from the blood, dialysis or a kidney transplant may be needed .

Aneurysms . For those with polycystic kidney disease and a family history of aneurysm, your doctor may recommend periodic screening for intracranial aneurysms. 
When an aneurysm is discovered, a surgical cut of the aneurysm may be performed to reduce the risk of bleeding depending on the size. 
Non-surgical treatment of small aneurysms involves controlling high blood pressure, high cholesterol, and stopping smoking .

Prevention
Since it is a genetic disease, there is no method of prevention. 
Whoever has polycystic kidney disease should make an effort to keep the kidneys in a healthy state at all times. For this it is necessary to follow a diet recommended by the doctor, maintain a healthy weight and exercise regularly.

Pregnancy
Most women can get pregnant even with this disease.

 


What is the life expectancy? The prognosis

Life expectancy depends on many factors: the age of the individual and the complications of the disease. 
Polycystic kidney disease is a disease that causes kidney failure and uremia in the final phase. 
At 75 years, 50-75% of patients with autosomal dominant polycystic kidney disease need dialysis or kidney transplantation , so the patient can live for a long time.

 


Diet and diet for polycystic kidney disease

The goal of a special diet is to try to facilitate the proper functioning of the kidneys. The following diet for DRP helps to do just that:

Reducing Protein Content
Proteins are processed by the kidneys more slowly. 
The product of protein residues is called urea. The basic function of the kidney is the removal of urea from the body. 
Therefore, a large amount of protein produced by the liver causes a higher production of urea.

There is only one exception when it comes to protein
. Soy is a type of excellent protein to control this disease. Soy-based foods like tofu, tempeh and miso should become a key part of the kidney diet.

According to a study published in the Pubmed ( Dietary soy protein effects on inherited polycystic kidney disease are influenced by gender and protein level ), animals that followed a diet with soy proteins had an improvement in the size of cysts and kidneys compared to those fed with casein.

Increase
omega-3 content Omega-3 fatty acids help reduce the formation of renal cysts thanks to anti-inflammatory , antihypertensive and lipid-lowering properties . 
Fish is a rich source of omega-3 essential fatty acids. 
Flaxseed oil and walnuts are considered rich in this fatty acid and therefore must be present in the diet for the kidneys.

Consume little salt and sugar
Excess salt, alters the balance of minerals in the kidneys and raises blood pressure in people affected by PRD. 
Excessive sugar consumption can cause insulin resistance more quickly in these patients. 
People with polycystic kidney disease should completely avoid artificial sugar and opt for fruits and fruit juices.

Adjust potassium intake
Potassium is part of the diet for DRP.

Taking more potassium in the early stage of DRP
In the early stage, renal cysts are small and do not affect renal function, so patients’ kidneys can usually eliminate potassium . 
Therefore, a diet rich in potassium is important for the prevention of high blood pressure. 
It is necessary to eat foods rich in potassium, such as sweet potatoes, papaya, plums, raisins, cantaloupe, oranges, mangoes, pears and molasses.

Limit potassium-rich foods in the advanced polycystic kidney
In the final phase, most renal tissue was replaced by cysts. 
Because the kidney can not adequately filter blood, potassium is more likely to accumulate in the body. 
Increased potassium levels in the blood may contribute to the onset of heart disease.

 

Natural treatment for polycystic kidney

Often, to solve illnesses it is enough to follow a healthy lifestyle with regular exercise and natural nutrition. 
There are several theories about diet, among the most effective is the blood type . 
According to the creators of this diet (Dr. D’adamo and Dr. Mozzi), even if a patient has a genetic predisposition to the disease, following a correct diet does not develop symptoms and consequences. 
In particular, milk and dairy products are responsible for the development of the polycystic kidney.

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