From the Guidelines
Screening for Polycystic Kidney Disease (PKD) should typically involve abdominal imaging by ultrasound to screen adults at risk, as recommended by the most recent guidelines 1. The most common initial screening method is ultrasound, which can detect kidney cysts non-invasively.
- For adults with a family history of autosomal dominant PKD (ADPKD), ultrasound is highly reliable after age 30, with MRI or CT scans sometimes used for more detailed imaging when needed 1.
- Genetic testing is also available to identify mutations in the PKD1 or PKD2 genes for ADPKD, or PKHD1 for autosomal recessive PKD (ARPKD), and is particularly valuable for younger patients where imaging might not yet show cysts, for family planning purposes, or when diagnosis is uncertain 1.
- Blood and urine tests are also part of screening to assess kidney function through measurements like creatinine levels, estimated glomerular filtration rate (eGFR), and checking for protein or blood in urine.
- For at-risk individuals, screening should begin in early adulthood, with regular monitoring of blood pressure as hypertension is a common early sign of PKD.
- Children with a family history of ARPKD should be screened earlier, often at birth or during infancy, as this form can cause serious complications early in life 1. Key considerations in screening for PKD include:
- Age-specific numbers of cysts have been described to diagnose or exclude ADPKD in people with a positive family history 1.
- The Mayo Imaging Classification (MIC) can be used to predict future decline in kidney function and the timing of kidney failure (KF) 1.
- Genetic testing may not provide a definitive diagnosis if detected mutations have unknown pathogenicity, and there are issues related to cost and insurance coverage of the test 1.
From the Research
Screening for PKD
To screen for Polycystic Kidney Disease (PKD), several methods can be employed, including:
- Renal function testing
- Abdominal imaging, such as ultrasonography, computed tomography, or magnetic resonance imaging (MRI) 2, 3
- Comprehensive PKD1 and PKD2 mutation screening 4
- Total kidney volume measurement using MRI, which can be an important marker for disease progression and overall prognosis 3, 5
Imaging Techniques
Imaging studies play a crucial role in the diagnosis, monitoring, and detection of complications in PKD. The following imaging techniques can be used:
- Ultrasonography, which has specific criteria for diagnosis in children and adults 3
- Computed tomography, which can help detect extrarenal manifestations such as intracranial aneurysms and cystic liver diseases 2
- Magnetic resonance imaging, which can measure total kidney volume and assess disease progression 3, 5
Atypical PKD
Atypical PKD, defined by imaging, can represent a distinct prognostic group with a low likelihood of progression to chronic kidney disease (CKD) 6. Patients with atypical PKD by imaging tend to be older, less likely to have a family history of ADPKD, and less likely to have a detectable PKD1 or PKD2 mutation 6.
Diagnostic Approach
A diagnostic approach to PKD may involve: