Renal: Embryology

Question 1

• Week 4 then degenerates

Answer 1

Pronephros

Question 2

• Functions as Interim Kidney for 1^st Trimester
• Later contributes to Male Genital system

Answer 2

Mesonephros

Question 3

• Permanent
• First appears in 5th week of Gestation
• Nephrogenesis continues through 32 - 36 weeks of Gestation

Answer 3

Metanephros

Question 4

• Derived from Caudal end of Mesonephric duct
• Gives rise to Ureter, Pelvises, Calyces, and Collecting ducts
• Fully canalized by 10th week

Answer 4

Ureteric bud

Question 5

• Ureteric bud interacts with this tissue
• Interaction induces differentiation and formation of Glomerulus through to the Distal Convoluted Tubule

Answer 5

Metanephric mesenchyme

Question 6

Aberrant interactions between the ______, and _______
(2 tissues) may result in several congenital malformations of the Kidney?

Answer 6

Ureteric bud

Metanephric mesenchyme

Question 7

• Last to Canalize → most common site of obstruction (hydronephrosis) in Fetus

Answer 7

Ureteropelvic junction

Question 8

• Compression of developing Fetus
  → limb deformities, facial anomalies
• Low-set ears and Retrognathia (recessed jaw) and compression of chest
  → Pulmonary hypoplasia (cause of death)
• Causes:
  
  • ARPKD
  • Posterior Urethral valves
  • Bilateral Renal agenesis

Answer 8

Oligohydramnios

Question 9

POTTER syndrome is a/w?

Answer 9

POTTER syndrome

• Pulmonary hypoplasia
• Oligohydramnios (trigger)
• Twisted face
• Twisted skin
• Extremity defects
• Renal failure (in utero)

Question 10

• A/w Turner syndrome
• Inferior poles of both Kidneys fuse
• As they ascend from Pelvis during fetal development, they get trapped under the Inferior Mesenteric Artery (IMA) and remain low in the Abdomen
• Kidney functions normally
• ↑ Risk for Ureteropelvic junction obstruction
• Hydronephrosis, Renal stones, and rarely Renal cancer (Wilms tumor)

Answer 10

Horseshoe Kidney

Question 11

• Abnormal interaction between Ureteric bud and Metanephric mesenchyme
• Leads to a Nonfunctional Kidney
• Consists of Cysts and Connective tissue
• Unilateral (most common)
• Generally Asymptomatic w/ Compensatory Hypertrophy of Contralateral Kidney
• Dx: Prenatally w/ Ultrasound

Answer 11

Multicystic Dysplastic Kidney