Diagnostic Criteria and Management of Autosomal Dominant Polycystic Kidney Disease (ADPKD)

Diagnostic Criteria

For adults with a positive family history of ADPKD, the American College of Physicians recommends beginning with renal ultrasonography and applying age-specific cyst thresholds: ≥3 total kidney cysts (ages 15-39), ≥2 cysts in each kidney (ages 40-59), or ≥4 cysts in each kidney (ages ≥60) to confirm diagnosis 1
The International Society of Nephrology suggests that diagnosis can be confirmed with ≥3 total kidney cysts (both kidneys combined) for ages 15-39, ≥2 cysts in each kidney for ages 40-59, or ≥4 cysts in each kidney for ages ≥60 1, 2
For children under 15 years, the presence of ≥1 kidney cyst on ultrasound is highly suggestive of ADPKD, with 89% specificity under 5 years and 100% specificity over 5 years 3, 4

The American College of Radiology recommends that MRI has greater sensitivity for detecting smaller cysts compared to ultrasound, particularly in ages 16-40 years 5
The National Institute of Diabetes and Digestive and Kidney Diseases suggests that CT with or without contrast can also be used as an alternative to MRI 1

The European Renal Association recommends starting with abdominal ultrasound as first-line imaging for adults with known family history, followed by application of age-specific ultrasound criteria, and proceeding to MRI or genetic testing if results are equivocal or atypical 1, 2
For adults without known family history, the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines suggest proceeding to kidney MRI (or CT) if few cysts are present with normal kidney function/size and no extrarenal features, and proceeding directly to genetic testing if multiple cysts, discordant imaging/GFR, or atypical renal/extrarenal findings are present 1

The American Society of Nephrology recommends genetic testing for ADPKD, particularly in scenarios such as few kidney cysts with suggestive clinical picture, variable intrafamilial disease severity, discordant imaging and glomerular filtration rate, negative or indeterminate family history, young living-related kidney donors at risk, and family planning considerations 1, 3, 4
The use of comprehensive multigene cystic kidney disease panels is recommended rather than testing single ADPKD genes (PKD1/PKD2 only) 3, 4

The Mayo Clinic recommends employing the Mayo Imaging Classification (MIC) to predict future kidney function decline and timing of kidney failure once ADPKD is confirmed, which divides ADPKD into typical (class 1) and atypical (class 2) presentations 1, 3
The MIC stratifies patients into 5 risk groups (1A-1E) indicating accelerating decline in kidney function, with prognostic information valid only for class 1 patients with typical imaging findings 1, 3