Kidneys Flashcards
Imaging findings AML
Hyperechoic, post acoustic shadowing on US
Most contain fat!! (5% are fat poor)
India ink artifact on MR
Multiple = TS
DDx fat poor AML
- RCC (often has calcs, focal or diffuse signal loss seen in clear cell as opposed to india ink artifact)
- Retroperitoneal liposarcoma (look for large feeding vessel, renal parenchymal defect/claw sign - both seen in AML)
- Oncocytoma
- Wilms
Imaging findings oncocytoma
Can look similar to RCC (for this reason they are excised)
Round, circumscribed, spoke wheel pattern of vessels +/- central fibrous scar
Need to remove, bx not helpful as RCC also has oncocytic elements
Imaging appearances of TB
If you see 3 or more of:
- renal calcification
- infundibular stricture
- papillary necrosis
- caliectasis
- renal scarring
- irregular urothelial thickening
suggest TB!
Imaging findings in XGP
Enlarged kidney, loss of corticomedullary differentiation, dilated calyces (bear paw), large staghorn calculus
DDx: Renal TB
Imaging findings HIV nephropathy
Enlarged, echogenic kidneys
Other associations with ADPKD
- Cerebral aneurysms (5-15%)
- Cyst in liver, seminal vesicles, pancreas, spleen
- Hypertension
- Cardiac (mv prolapse, bicuspid AV**, dissection)
NB: no increased risk of RCC (but acquired cystic disease from long term renal failure/dialysis does have increased RCC risk)
List the complications seen on imaging post renal transplant
- Renal Transplant Compartment Syndrome (RTCS)
- AVF or pseudoaneurysm post-bx
- Ureteral obstruction
- Fluid collection (hematoma immediate-5 days, 10 days urinoma, weeks to months abscess, 2wks-6mos lymphocele)
- Renal artery thrombosis (rare, immediate post-op)
- Renal vein thrombosis (immediately post op to 5 days)
- Renal artery stenosis (3 months to 2 years after surgery)
Frequency of PTLD in renal transplants? Cause? Imaging appearance?
1-3% (can be up to 20% in non-renal transplants)
EBV virus in immunocompromised host
Solitary or multiple low attenuation masses
May encase hilum
Causes of medullary calcinosis
HAMHOP HyperPTH Acidosis (RTA) - distal, type 1 Medullary sponge kidney Hypercalcemia (MM, bone mets) Oxalosis Papillary necrosis Child: furosemide
Causes of cortical nephrocalcinosis
COAG Cortical necrosis Oxalosis Alport syndrome Glomerulonephritis
Weigert-Meyer rule
Upper moiety OBSTRUCTS (has ectopic insertion medial and inferior to normal ureter +/- ureterocele)
Lower moiety REFLUXES
Causes/RFs for papillary necrosis
- Diabetes
- Analgesic abuse, high dose NSAIDS
- Sickle cell
- Chronic infection (TB, pyelonephritis)
- Renal vein thrombosis
- Obstructive uropathy
Imaging findings of papillary necrosis
Nephrographic phase - reduced perfusion in papilla
Excretory phase - ball on tee, lobster claw sign (forniceal blunting), sloughed papilla, calyceal blunting/clubbing
What are Hutch diverticula?
Diverticula located at the UVJ, congenital containing all 3 layers of bladder wall, contiguous with the bladder lumen, cause of reflux in boys and young men
(ddx: acquired bladder diverticula)
Type of malignancy that forms in urethral diverticulum
Adenocarcinoma
Location of skene duct cyst
Adjacent to external urethral meatus, below level of pubic symphysis (inflammatory obstruction of peri-urethral ducts)
What is page kidney?
Systemic HTN secondary to extrinsic compression of kidney by sub-capsular collection
Most common location of fused kidney in crossed fused renal ectopia? Where does ectopic kidney fuse?
Left side, lower pole
DDx for plaque like thickening of renal pelvis and collecting system
Urothelial cell ca
Malakoplakia (chronic granulomatous infection causing multi-focal plaques)
Ureteritis cystica
TB
Risk factors urothelial cell cancer
Smoking**
Chemical exposure
Cyclophosphamide
Which bugs cause XGP?
Proteus, E.coli (sometimes staph)
Pathologic findings in XGP
Mass like collection of lipid-laden macrophages
Imaging findings in XGP
Staghorn calculus
Contracted renal pelvis
Dilated calyces
**Soft tissue/perinephric extension
Most common cause of vas deferens calcification
Diabetes (ddx: TB, schistosomiasis)
Causes of renal artery stenosis
Atherosclerosis FMD Dissection Vasculitis NF
