Definition & Overview
Polycystic Kidney Disease (PKD) is a kidney disorder characterized by the formation of noncancerous cysts that impair kidney functions and eventually cause total kidney failure.
The cysts that develop in cases of PKD may not be cancerous, but the disorder doesn’t only affect the kidneys. There is a possibility for the cysts to spread to other organs, such as the liver, heart, and brain and this can lead to a heart murmur, brain aneurysm or even stroke or death.
There are three classifications of PKD: Autosomal Recessive PKD (ARPKD), Autosomal Dominant PKD (ADPKD), and Acquired Cystic Kidney Disease (ACKD). Of the three types, only ACKD is not inherited.
Ninety percent of PKD cases are ADPKD (inherited), mainly because only one parent needs to have the disease in order to pass it down to their child. The child may already show symptoms early in life, but these usually appear when they reach 30 or 40 years old.
ARPKD is less common because both parents need to have the disorder in order to pass it down to the child. ARPKD is further classified into four types: perinatal, neonatal, infant, and juvenile. Each type is based on the age in life when the symptoms start to appear.
People who already have kidney problems are at risk of developing ACKD, especially if they are already undergoing dialysis due to kidney failure.
Cause of Condition
PKD is caused by gene abnormalities that can be passed down from parent to child. However, in rare cases wherein there is no family history of PKD, the disorder is caused by a genetic mutation.
If left untreated, PKD can cause a variety of complications, some of which can be life-threatening. Some of the most common complications are elevated blood pressure, cysts in the liver, reduced or total loss of kidney function, problems with the colon, chronic pain, brain aneurysm, and heart valve abnormalities.
Because most people with PKD have the disorder since childhood, it’s common for women to display symptoms during pregnancy. While most pregnancies with PKD turn out to be uneventful, there is a possibility for the woman to develop a condition called preeclampsia.
PKD may be a kidney disorder, but it affects other organs as well, which is why it will commonly display a variety of symptoms. Some of the most common symptoms are hypertension, blood in urine, urinary tract infections, kidney infections, kidney failure, increased abdominal size, back pain, headaches, and the need to urinate frequently.
It’s important to note that many people with PKD don’t display symptoms until later on in life. Many PKD patients don’t even know they have the disorder. Unfortunately, the absence of symptoms does not necessarily mean that the disorder is not already causing damage to the kidneys.
It’s imperative that you consult a doctor if you notice any of the above symptoms. If you’re asymptomatic (you don’t display any symptoms), but PKD runs in your family or if it’s present in a first-degree relative, you should also consult a doctor as a preventative measure.
Who to See & Types of Treatment Available
The majority of the symptoms of PKD are also associated with a wide variety of diseases and disorders. It’s likely that you’ll need to consult a doctor and mention one or more of the symptoms as your primary complaint. Your doctor will then review your medical history and perform a physical examination. You will likely need to undergo several laboratory tests, such as a complete blood count (CBC) and urinalysis, to determine the cause of the symptoms.
If your doctor suspects PKD, he or she will review your family history. You will then be referred to a specialist for further diagnosis of your condition and treatment.
Once a specialist takes on your case, you’ll undergo further diagnostic tests to determine the cause of the condition and how far it has spread in your body. Remember that the cysts do not only affect the kidneys, but can spread to other organs as well.
The most common diagnostic tests include an abdominal ultrasound to look for cysts in the abdomen; an abdominal CT scan or X-ray to find smaller cysts; an abdominal MRI to view the condition of your kidneys; and an intravenous pyelogram so that the blood vessels will appear clearly on an x-ray.
If the specialist suspects that there is a risk of brain aneurysm, you’ll also undergo a cerebral angiography.
Once the specialist has confirmed what organs in the body have been affected by PKD, you’ll be presented with a treatment plan. It’s important to understand that treatment for PKD involves controlling the symptoms, most especially high blood pressure, which is the primary cause of a wide variety of medical problems, such as kidney failure and heart diseases.
Your treatment will also include medications to alleviate pain, antibiotics to treat infections, diuretics to remove excess fluid, and surgery to drain the cysts. You’ll also be given a low-salt diet to reduce the chances of fluid retention.
If PKD has significantly affected the kidneys, dialysis will be recommended to prevent waste products from building up in your bloodstream. If both of your kidneys fail, a kidney transplant will be required.
With the right treatment and lifestyle changes, most people with PKD are able to live normal lives. However, in some people, PKD slowly progress causing liver diseases or kidney failure. If the problem is concentrated in the kidneys, a kidney transplant will help you continue your life normally.
Patients with PKD will need plenty of support from friends and family members. In some cases, the patient will also need to undergo counselling to help him or her cope with the condition. Fortunately, a number of support groups are dedicated to helping PKD patients live fruitful lives despite the disorder.
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