Module 9: GU Flashcards
The ureteric buds form from what?
Wolffian ducts
What do the ureteric buds become?
Ureters, renal pelvis, calyces, and collecting tubules
The metanephros gives origin to what?
Nephrons
When does fetal urine production begin?
Around 11 weeks LMP
What is the metanephros also known as?
Primitive kidney
Where is the primitive kidney located early on?
Pelvis
What would cause an ectopic kidney?
Failure of primitive kidney migration
What is a normal renal pelvis fullness in a fetus?
<3mm
What renal pelvis fullness would require further investigation?
> 5mm
What is the terminal end of the hindgut called?
Cloaca
What compartments are the cloaca divided into?
Urinary and rectal
The caudal end of the cloaca forms what?
Urethra and bladder neck
The rest of the bladder is derived from what?
Allantois
Where does the allantois end?
The urachus
Where do the mesonephric ducts enter the bladder?
Posterior wall of the bladder at the trigone
When are fetal genitals in an ambiguous state?
Prior to 8 weeks LMP
When are normal male genitalia formed?
8-10 weeks when testosterone is present
What is bilateral renal agenesis associated with?
Other GU abnormalities, GI abnormalities, cardiac abnormalities, sirenomelia-mermaid syndrome, and teratogens
What kind of teratogens are bilateral renal agenesis associated with?
Warfarin, cocaine, and type 1 maternal diabetes
What could be mistaken for kidneys with bilateral renal agenesis?
Adrenals that assume a discoid shape
What would you expect to see sonographically with bilateral renal agenesis?
Absent bladder, IUGR, and oligohydramnios
What does Potter’s syndrome refer to?
Bilateral renal agenesis
What does Potter’s sequence refer to?
Consequence of severe oligohydramnios
What are things you would see with Potter’s sequence?
Pulmonary hypoplasia, abnormal hand and foot positions, and facial anomalies
What are some examples of abnormal foot and hand positions seen with Potter’s sequence?
Bowed legs, clubbed feet, and hip dislocation
What are some examples of abnormal facial features you’d expect to see with Potter’s sequence?
Beaked nose, low set ears, prominent epicanthic folds, and hypertelorism
75% of all renal abnormalities will be what?
Hydronephrosis
What are three causes of hydronephrosis?
Obstruction, reflux, and ureterocele
Where is the level of obstruction if there is only hydronephrosis with only dilated kidneys?
Ureteropelvic junction
Where is the level of obstruction if there are dilated ureters with hydronephrosis?
Ureterovesical junction
Where is the level of obstruction if there is a dilated bladder and keyhole appearance?
Posterior urethral valve
What is Grade I hydronephrosis?
Involves renal pelvis only
What is Grade II hydronephrosis?
Involves visible renal pelvis and calyces
What is Grade III hydronephrosis?
Involves dilation of renal pelvis and calyces
What is Grade IV hydronephrosis?
Involves parenchymal thinning
What is the most common urinary obstruction in neonates?
Ureteropelvic junction obstruction
What will you see with unilateral UPJ obstruction?
Normal bladder and amniotic fluid
What will you see with bilateral UPJ obstruction?
Oligohydramnios with hydronephrosis of varying degrees
What may be destroyed with severe UPJ obstruction?
Renal parenchyma
An extra renal pelvis under 1.5cm may mimic what?
Small hydronephrosis
What is UVJ obstruction usually due to?
Duplicated collecting system with an ectopic ureter location from the upper pole of the kidney
A ureter may mimic bowel. How can you tell the difference?
Bowel is medial and ureter was lateral in the abdomen
What is an ectopic ureter associated with?
Ureterocele in the bladder
What is a ureterocele?
Cystic dilation of the intravesicular portion of the ureter
What is a PUV?
Posterior urethral valve
What membranes obstruct the retrograde flow of urine in a male fetus?
Posterior urethral valves
Prune belly syndrome is also known as what?
Eagle-Barrett syndrome
What is undescended testicles also known as?
Cryptorchidism
What will you see sonographically with a fetus with infantile polycystic kidney disease?
Bilateral grossly enlarged echogenic kidneys, severe oligohydramnios, and absent bladder
What is IPKD (infantile polycystic kidney disease) associated with?
Meckel-Gruber syndrome, Robert’s syndrome, and trisomy 13
What is a DDx of IPKD?
Benign glomerulosclerosis
What does adult polycystic kidney disease look like on a fetus?
Enlarged kidneys with cysts
Bilateral multicystic dysplastic kidney is associated with what?
Potter’s sequence
What is a Wilm’s tumor also known as?
Nephroblastoma
What is a nephroblastoma?
Solid mass not commonly identified in utero
What is the most common congenital renal tumor?
Mesoblastic nephroma
