Embryology

Question 1

How long does pronephros stay?

Answer 1

Week 4; then degenerates.

Question 2

What is the function of the mesonephros?

Answer 2

Function as interim kidney for 1st trimester; later contributes to male genital system.

Question 3

When is Metanephros first seen?

Answer 3

First appears in 5th week of gestation.

Question 4

How long does nephrogenesis continue?

Answer 4

Nephrogenesis continues through weeks 32-36 of gestation.

Question 5

What does the ureteric bud derive from?

Answer 5

Caudal end of mesonephric duct

Question 6

What is another name for ureteric bud?

Answer 6

Metanephric diverticulum

Question 7

What is formed from the ureteric bud?

Answer 7

Gives rise to ureter, pelvises, calyces, collecting ducts.

Question 8

What induces glomerular differentiation and formation?

Answer 8

Metanephric mesenchyme (ie, metanephric blastema) - ureteric bud interacts with this tissue; and interaction induces.

Question 9

When is the ureteropelvic junction canalized?

Answer 9

Last to canalize

Question 10

What is the most common cause of prenatal hydronephrosis?

Answer 10

Congenital obstruction

Question 11

What are the diseases associated with the potter sequence?

Answer 11

Pulmoner hypoplasia
Oligohydroamnios (trigger)
Twisted face
Twisted skin
Extremity defects
Renal failure (in utero)

Question 12

Potter syndrome etiology?

Answer 12

Autosomal recessive polycystic kidney disease (ARPKD)
Obstructive uropathy (eg, posterior uretral valves)
Bilateral renal agenezis
Chronic placental insufficiency

Question 13

Potter syndrome pathogenesis?

Answer 13

Oligohydroamnios
↓
Compression of developing fetus
↓
Limb deformities, facial anomalies (eg, low-set ears, retrognathia, flattened nose), compression of chest and lack of amniotic fluid aspiration into fetal lungs
↓
Pulmoner hypoplasia

Question 14

What is the cause of death of patients with potter syndrome?

Answer 14

Pulmoner hypoplasia

Question 15

What diseases are associated with horseshoe kidney?

Answer 15

Hydronephrosis (eg, ureteropelvic junction obstruction)
Renal stones
Infection
Increase risk of renal ca
Chromosomal aneuploidy (eg, Turner syndrome, trisomies 13,18,21)

Question 16

What is an anomaly in the horseshoe kidney?

Answer 16

Inferior poles of both kidneys fuse abnormally. As they ascend from pelvis during fetal development, horseshoe kidneys get trapped under inferior mesenteric artery and remain low in the abdomen.

Question 17

What is the function of the horseshoe kidney?

Answer 17

Kidneys function normally.

Question 18

Under which artery is the horseshoe kidney trapped?

Answer 18

Inferior mesenteric artery

Question 19

Why congenital solitary functioning kidney is asymptomatic?

Answer 19

Cause compensatory hypertrophy of contralateral kidney. But anomalies in contralateral kidney ar common.

Question 20

What form of multicystic dysplastic kidney disease leads to potter sequence?

Answer 20

Bilateral form

Question 21

What diseases is the duplex collecting system associated with?

Answer 21

Vesicoureteral reflux (strongly associated)
Ureteral obstruction
Increase risk for urinary tract infections (UTIs)

Question 22

What is the most common cause of bladder outlet obstruction in male infants?

Answer 22

Posterior urethral valves disease

Question 23

Posterior urethral valves pathogenesis?

Answer 23

Membran remnant in the posterior urethra in males
↓
Urethral obstruction
↓
Bilateral hydronephrosis and dilated or thick walled bladder

Question 24

What are the features of multicystic dysplastic kidney?

Answer 24

Nonfunctional kidney consisting of cycts and connective tissue.
Predominantly nonhereditery.
Usually unilateral.