How Polycystic Kidney Disease Is Diagnosed

If your healthcare provider suspects you have polycystic kidney disease (PKD), they will likely use imaging tests to diagnose the condition. Imaging tests such as ultrasounds, CT scans, and MRI tests can detect how many cysts you have on your kidneys and what size they are.

This article will explain how a person can be diagnosed with PKD through testing and imaging.

At-Home Testing

PKD is an inherited disease. The most common genetic mutations responsible for PKD are the PKD1 gene and PKD2 gene.  At-home genetic tests can be done, but these tests can be expensive. Additionally, genetic testing fails to detect any genetic abnormalities in about 15% of individuals affected with PKD.

Physical Examination

People affected by the most common form of polycystic kidney disease, autosomal dominant polycystic kidney disease, experience the following symptoms:  

• Headaches  
• Hematuria (blood in the urine)  
• High blood pressure  
• Pain in the back or sides  
• Frequent urinary tract infections (UTIs)
• Unexplained abdominal swelling  

It is estimated that about half of people affected by autosomal dominant polycystic kidney disease are unaware they have polycystic kidney disease.

Labs and Tests

To detect polycystic kidney disease, genetic testing may be ordered. There are some circumstances in which genetic testing might be valuable in determining a PKD diagnosis, including when:

• Imaging studies do not indicate clear evidence of PKD.
• An individual wants to donate a kidney but had a family history of PKD.
• An individual younger than 30 years old with a family history of PKD and a negative ultrasound is interested in starting a family.

Imaging

The most reliable test to diagnose PKD is ultrasound. Also known as a sonography, , a clinician administering this noninvasive test uses a small, handheld probe to transmit sound waves and record the waves that echo back to crate an image of the area being studied.

For an individual with a known family history of PKD, a computed tomography (CT) scan or a magnetic resonance imaging (MRI) scan might be ordered to identify cysts that are too small for ultrasound to identify.

Differential Diagnosis

Not all kidney cysts are harmful or mean you might be diagnosed with PKD. Simple, non-PKD kidney cysts can form in the tubes inside the kidney and swell with fluid. It is not known why these simple cysts form, but researchers hypothesize they result from a blockage within the tubes.

Most of the time, these simple kidney cysts do not interfere with the function of the kidneys and individuals affected by them often have no symptoms. However, if the cyst becomes infected or ruptures, it can cause pain in the back or sides, fever, frequent urination, or blood in the urine.

It is important to find a healthcare professional with an expertise in kidney diseases, such as a nephrologist, to evaluate symptoms, take a family history, and perform appropriate testing to determine if you have simple kidney cysts or PKD.

Summary

Polycystic kidney disease is an inherited disorder caused by genetic mutations that can be tested for, usually by ultrasound. At-home genetic tests are available but not recommended as they tend to not be as reliable when it comes to detecting PKD. Additionally, anyone with a known family history of PKD should be aware of symptoms associated with the disease and seek professional medical advice if these symptoms persist.

A Word From Verywell

Facing the possibility of getting a diagnosis of an inherited disease like PKD can be overwhelming and upsetting. Collaborating with a healthcare professional with an expertise in kidney diseases, such as a nephrologist, can be important if PKD is a possibility in your family.

Although there is no cure for PKD, a nephrologist can ensure close monitoring and provide advice on lifestyle modifications, such as a healthy diet and managing blood pressure, to prevent further stress to the kidneys. It is possible to maintain a good quality of life, even with a diagnosis of PKD.