Polycystic Kidney Disease

What is Polycystic Kidney Disease?

Polycystic Kidney Disease (PKD) is a kidney disorder which carries forward from generation to generation of a family, as it transferred via genetically. This inherited disease can transfer via abnormal gene from one parent who already has polycystic kidney disease. This type of disease passed down process is also termed as an autosomal dominant trait.

Image 1: Polycystic kidney disease

In polycystic kidney disease, non-malignant cysts are formed which are usually filled with water like liquid substance and gradually interfere in kidney functioning and progress to kidney failure. This is one of the major causes of kidney damage, but it can also spread to the liver and raise the complications.

Symptoms

Almost one fourth patient with PKD have a chest pain with fluttering or throbbing sensation in the heart due to floppy valve.

Image 2: symptoms of polycystic disorder

Other common symptoms associated with PKD are:

• High blood pressure: almost every individual with PKD has increased blood pressure and which affect kidney functioning.
• Head ache
• Pain in both side of the back
• Urinary tract infection
• Urinary bladder infection
• Kidney infection
• Haematuria (Blood in urine)
• Abdominal size enlargement
• Polyuria (large quantity of urine passage with frequent urination)
• Stone formation in kidney

Other than these symptoms, patients also reported

• Joint pain
• Fatigue
• Pallor skin
• Discolouration of skin
• Brittle nail

Causes

• PKD passes down through heredity. Hereditary transferring the abnormal gene from one diseased parent to his or her child causes 50% autosomal dominant PKD. The reported cases caused 90% of PKD incidence due to autosomal dominant PKD. The onset of disease symptoms often reported after 30 years of age, but sometimes children also suffer from autosomal dominant PKD.
• Another form is an autosomal recessive PKD. This disease develops after birth or in childhood. In rare cases, the disease is diagnosed at adolescent. This disease worsens the kidney and liver functioning rapidly. The chance of development of autosomal recessive PKD is due to both the parent carrying abnormal gene.

Some parents unaware about their PKD, because the onset of symptom not arises at their life time.

Image 3: Cause of polycystic kidney

In rare cases, people with malfunctioning in gene mutation which ultimately creates anomaly in DNA structure due to abnormal protein formation. Abnormal protein formation is not functioning in a normal way for growth and development of the tissues, but creates genetic abnormality.

Diagnosis

To diagnose the PKD, the essential step is to through knowledge of family history, as it is an inherited disorder. Initial diagnosis is start with blood pressure monitoring, blood tests and urine analysis.

• Blood tests are recommended for estimating haemoglobin and total blood count. Both these tests provide the information about anaemic condition and the chances of infection.
• Urine analysis helps to detect the infection present in the urinary system.

For confirmatory test, imaging techniques are used.

• Ultrasound: Usually a whole abdomen ultrasound recommends for detecting the presence of cysts.
• KUB- radiography: In case of very tiny cysts which are not visible in the ultrasound image, then KUB (kidney-ureter and bladder) radiography is conducted to detect the cysts. It is one type of CT scan.

Other than these, doctors can also prescribe to do the abdominal MRI and intravenous pyelogram.

• Abdominal MRI: In this test strong magnetic resonances use to take the internal images of the abdomen for visualizing the kidney cysts.
• Intravenous pyelogram: By using dye to make more prominent of blood vessels.
• If the doctor suspects that cerebral aneurysms due to PKD complication, then a cerebral angiography also may conduct for confirmation.

Treatment

Treatment of PKD is involved to control the associated symptoms and decrease the rate of disease progression.

• For controlling the disease progression one of the major steps is blood pressure control, as it affects kidney functioning. In case of hypertension, for controlling blood pressure doctors may recommend Angiotensin Converting Enzyme Inhibitor (Enalapril), Angiotensin blocking agent (Lisinopril), Beta blockers (atenolol) etc.
• In case of infection development in the urinary system, then broad spectrum antibiotics usually prescribed to control the infection.
• Analgesics which contain acetaminophen are usually beneficial for pain reduction.
• In case of enlarged size of the cyst, surgical removal can help to control the polyuria, pain and pressure.
• In case of kidney failure, dialysis and kidney transplant can expand the life expectancy of the patient.
• If cysts are extended to the liver, then partial liver surgical procedure may help to reduce the complication.
• Brain aneurysm is one of the complications of PKD which causes rupture of intracranial nerve. To control this regular screening is required to judge the progression, and in severe case, surgical clipping is beneficial for the reduction of internal brain haemorrhage.

Diet

Restricted diet and life style delay the worsening of the PKD and restrict the associated complications.

• Low salt diet and low fat diet are usually recommended for PKD patients as these help to control blood pressure and blood cholesterol level. Both these factors responsible for hypertension and heart disease and even they affect brain aneurysms.
• Smoking is totally restricted for PKD patient.

Life Expectancy

In autosomal dominant PKD, the onset of disease symptoms is after 30 or 40 years of age.  Kidney failure or other complications, mostly occur after 60 years of age. Life expectancy is normal for whom having well controlled BP and cholesterol, as they delay the worsening of the disease.

In autosomal recessive PKD, the onset of disease is early and disease progression is very fast. Life expectancy is low with autosomal recessive PKD.

References

1. http://www.healthline.com/health/polycystic-kidney-disease#Complications6
2. When to Consider Genetic Counseling? What are the complications of autosomal recessive polycystic kidney disease? at http://www.niddk.nih.gov/health-information/health-topics/kidney-disease/polycystic-kidney-disease-pkd/Pages/facts.aspx
3. Does everyone with PKD develop kidney failure?, Should people with PKD take a special diet? at https://www.kidney.org/atoz/content/polycystic
4. https://www.nlm.nih.gov/medlineplus/ency/article/000502.htm
5. Polycystic kidney disease Drugs, Treatment, Diagnosis, Coping at http://www.mayoclinic.org/diseases-conditions/polycystic-kidney-disease/basics/treatment/con-20028831