Renal embryology

Question 1

Oligohydramnios

Answer 1

Bilateral agenesis (incompatible with life)

Question 2

Lung hypoplasia, flat face with low set eats, and developmental defects of extremities

Answer 2

Potter sequence of bilateral agenesis

Question 3

Noninherited, congenital malformation of the renal parenchyma characterized by cysts and abnormal tissue (e.g. cartilage)

Answer 3

Dysplastic kidney (usually unilateral in real life, but bilateral on step 1)

Question 4

inherited defect –> bilateral enlarged kidneys with cysts in renal cortex and medulla

Answer 4

Polycystic kidney disease (PKD)

Question 5

PKD that presents in young adults with HTN (inc renin), hematuria, and worsening renal failure

Answer 5

autosomal dominant PKD

Question 6

Mutations in APKD1 or APKD2 –> development of cysts in kidneys over time

Answer 6

AD PKD

Question 7

AD PKD is associated with three things

Answer 7

berry aneurysm (cause of death),
hepatic cysts,
mitral valve prolapse

Question 8

Inherited (AD) defect –> cysts in medullary collecting ducts –> parenchymal fibrosis resulting in shrunken kidneys and worsening renal failure

Answer 8

Medullary cystic kidney disease

Question 9

Conjoined kidneys usually connected at the lower pole; most common kidney anomaly

Answer 9

horseshoe kidney

Question 10

What does horseshoe kidney get stuck on during embryogenesis?

Answer 10

IMA

Question 11

absence of kidney formation

Answer 11

renal agenesis

Question 12

Leads to hypertrophy of existing kidney –> hyper filtration increased the risk of renal failure later in life

Answer 12

unilateral agenesis

Question 13

PKD that presents in infants with worsening renal failure, HTN, & potter sequence

Answer 13

Autosomal recessive PKD

Question 14

AR PKT is associated with

Answer 14

congenital hepatic fibrosis, hepatic cysts –> portal hypertension

Question 15

“kidney” that exists till week 4 of fetal life, then degenerates

Answer 15

Pronephros

Question 16

functions as interim kidney for 1st trimester; laster contributes to male genital system

Answer 16

Mesonephros

Question 17

permanent kidney; first appears in 5th week of gestation; nephrogenesis continues through 32-36 weeks of gestation

Answer 17

Metanephros

Question 18

Derived from caudal end of mesonephros; gives rise to ureter, pelvises, calyces, and collecting ducts; fully canalized by 10th week

Answer 18

ureteric bud

Question 19

Ureteric bud interacts with this tissue; interaction induces differentiation and formation of glomerulus through to DCT

Answer 19

Metanephric mesenchyme

Question 20

last to canalize - most common site of obstruction (hydronephrosis) in the fetus

Answer 20

Ureteropelvic junction

Question 21

aberrant interaction between these two tissues may result in several congenital malformations of the kidney

Answer 21

ureteric bud, metanephric mesenchyme

Question 22

Oligohydramnios –> compression of fetus –> limb deformities, facial deformities, and pulmonary hypoplasia (COD)

Answer 22

Potter’s syndrome

Question 23

Babies who can’t Pee in utero develop

Answer 23

Potter’s

Question 24

Causes of Potter’s syndrome

Answer 24

ARPKD,
posterior urethral valves
bilateral renal agenesis

Question 25

genetic condition associated with horseshoe kidney

Answer 25

Turner syndrome

Question 26

inferior poles of both kidneys fuse –> trapped under IMA (remain low in abdomen), but kidney functions normally

Answer 26

Horseshoe kidney

Question 27

Abnormal interaction between ureteric bud and metanephric mesenchyme –> nonfunctional kidney consisting of cats and connective tissue

Answer 27

Multicystic dysplastic kidney

Question 28

Unilateral multicystic dysplastic kidney

Answer 28

generally asymptomatic with compensatory hypertrophy of contralateral kidney

Question 29

diagnosis of multi cystic dysplastic kidney

Answer 29

usually prenatally via ultrasound