Renal Cysts Flashcards
Three types of renal cysts?
simple (Bosniak category 1), complex (Bosniak category 2) , cystic mass (Bosniak category 3 and 4)
imaging findings of simple cyst?
round, thin, smooth and regular border
no septa, calcifications, solid components, posterior enhancement on U/S, and no contrast enhancement on CT scan or MRI
Tx of simple cysts
reassurance <1% malignancy risk
Findings on U/S of complex cysts
few septa, calcification, no contrast enhancement on CT scan or MRI
Bosnaik II <3 cm
Bosnaik IIF >3 cm
Tx of Complex Renal cysts
Bosnaik II: reassurance (<3% malignancy risk)
Bosnaik IIF: follow up imaging in 6 -12 months with a 5-10% malignancy risk.
Tx with Bosnaik II renal cyst
reassurance (<3% malignancy potential)
Tx of Bosnaik IIF renal cyst
repeat imaging in 6-12 months (5-10% malignancy risk)
Cystic mass findings
thick, irregular wall
multiple thick septa, often with calification
enhancement on CT scan/MRI (Category IV cysts have enhancing soft tissue components)
Tx of Cystic masses
surgical excision of mass or nephrectomy (>90% chance of malignancy)
Why do we see posterior wall enhancement in simple cysts?
technical artifact seen on U/S studies that indicates ultrasound wave transmission beyond the cyst and doesn’t equate with contrast enhancement on CGT scan or MRI.
Do we ever get a percutaneous needle aspiration of a renal cyst?
only indicated for lesions that demonstrate abscess or purulent fluid >10 cm and painful. Can check for malignancy if papillary renal cell carcinoma.
When do we see renal cysts?
simple renal cysts are seen in adults >50 yrs.
ultrasound characteristics of ppl with autosomal dominant polycystic kidney disease
Age 15-39 >3 unilateral or bilateral kidney cysts
Age 40-59 >2 cysts in each kidney
Age>60 >4 cysts in each kidney
Unknown family history
multiple (usually >10 in each kidney regardless of age)
other medical conditions associated with autosomal dominant polycystic kidney disease
hepatic cysts 20-80%, cerbral aneurysms 5-20% and cardiac valvular dx or mitral or aortic regurgitation and diverticulosis
how to confirm autosomal dominant polycystic kidney disease
genetic testing
how to monitor autosomal polycystic kidney disease
U/S and supportive care.
difference between medullary sponge kidney and ADPKD
Medullary spong kidney has dilated collecting ducts in the medullary pyramids that is sometimes confused for radiographic appearance of ADPKD.
major extrarenal complications of ADPKD
intracranial aneurysms
hepatic and pancreatic cysts
cardiac valve disease and aortic root dilation
diverticulosis
pt has hypertension, hematuria, proteinuria renal insufficiency and bilateral flank masses who presents with severe headache, altered mental status and nuchal rigidity. what does she have?
has possible subarachnoid hemorrhage as a result of ruptured intracranial aneurysm from her autosomal dominant polycystic kidney disease
who has highest risk for development of intracranial aneurysms with autosomal polycystic kidney disease?
>60 yrs old (20%) young adults (5%)
higher risk in pts with family history of ruptured aneurysms
screening for intracranial aneurysms is controversial in autosomal polycystic kidney disease because:
routine screens can see small aneurysms <7 mm that are low risk for rupture but surgical intervention of aneurysms can cause higher neurological complications
guidelines recommend screening pts with previous aneurysm rupture and family history of intracranial bleed or aneurysm and high risk occupations (pilots)
best screening test for intracranial aneurysms in pts with autosomal polycystic kidney disease
time of flight magnetic resonance angiography and can be done at any GFR.
CT angiography is alternate screening method.
