Intracranial Aneurysms in Autosomal Dominant Polycystic Kidney Disease: Current State of Practice

Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disorder primarily known for progressive kidney cysts, and it is the most common hereditary syndrome linked to intracranial aneurysms (IAs). Approximately 5–20% of ADPKD patients have IAs (versus ~3% in the general population). Key risk factors for IAs in ADPKD include a family history of aneurysmal subarachnoid hemorrhage (SAH), early-onset or poorly controlled hypertension, and possibly more severe kidney disease (e.g., large total kidney volume and reduced kidney function). The PKD1 and PKD2 mutations in ADPKD lead to polycystin-1/-2 dysfunction in vascular cells, causing intrinsic vessel wall weakness. This weakness—compounded by chronic hemodynamic stress and inflammation—predisposes ADPKD patients to aneurysm formation. Clinically, most aneurysms in ADPKD are small (<7 mm), asymptomatic, and located in the anterior cerebral circulation. Their growth and rupture risk appears similar to aneurysms in non-ADPKD patients; however, ruptures in ADPKD occur at younger ages, underscoring the need for vigilant management. This narrative review provides a nephrology-oriented overview of intracranial aneurysms in ADPKD, including pathophysiology, epidemiology, and clinical management. Key Messages: -ADPKD carries a higher prevalence of intracranial aneurysms (≈5–20%) than the general population (≈3%). Key risk factors include a family history of aneurysm/SAH, early or poorly controlled hypertension, and possibly advanced renal disease. -Guidelines support targeted rather than universal screening, mainly in patients with family history or prior SAH. -Non-contrast MRA is the preferred modality, usually initiated around age 30 in at-risk individuals. -Most aneurysms are small and asymptomatic; small lesions are monitored with BP control and imaging, while larger or high-risk aneurysms are treated prophylactically. -Broader screening remains debated. Future genetic insights may improve risk stratification, but current practice requires balancing rupture prevention against over screening.