Kidney embryology

Question 1

What two ductal structures develop in both male and female embryo

Answer 1

Wolffian/ Mesonephric ducts

Paramesonephric/ Mullerian ducts

Question 2

Where does mesenchyme run on the embryo

Answer 2

On either side of the embryo

Question 3

How do the ducts behave in female embryos

Answer 3

Mesonephric duct degenerates apart from lower portion which forms uteric bud
Paramesonerphic duct forms oviduct

Question 4

How do ducts behave in male embryo

Answer 4

Mesenophric duct forms the male reproductive truct and uteric bud
Paramesonephric duct degenerates

Question 5

How many kidney develop in the embryo

Answer 5

3

Question 6

What is the final, fully developed kidney called

Answer 6

Metanephric kidney

Question 7

What kidney do you start off with embryo-logically

Answer 7

Pronephric kidney

Question 8

Which two embryological kidneys form a duct system

Answer 8

Pronephric

Mesonephric

Question 9

Where are all 3 embryological kidneys formed from

Answer 9

Mesonephric duct

Question 10

What 2 embryonic structures is the metanephric kidney derived from?

Answer 10

Uteric bud from mesonephric duct

Metanephric bud derived from mesenchyme

Question 11

What is the site called where uteric bud comes into contact with mesenchyme

Answer 11

Metanephric bud

Question 12

What is derived from the uteric bud?

Answer 12

• Uterer
• Renal pelvis
• Major and minor calices
• Collecting tubules

Question 13

What is derived from metanephric bud

Answer 13

• Glomerulus and capillaries
• Bowmans capsule
• PCT
• Loop of henle
• DCT

Question 14

How many collecting tubules are found in kidney

Answer 14

1-3 million

Question 15

What do the major calyces bifurcate to form

Answer 15

Minor calyces

Question 16

What do minor calyces split to form

Answer 16

Collecting tubules

Question 17

What happens when mesenchyme comes into contact with the collecting tubule

Answer 17

It elongates

Question 18

What happens once the kidney has formed

Answer 18

It ascends within the embryo

Question 19

What happens as kidney grows and enlarges

Answer 19

It open out and moves upwards within embryo until it reaches final resting region

Question 20

Where does metanephros develop

Answer 20

S1

Question 21

What is final location of kidney

Answer 21

Upper lumbar region

Question 22

What is failure for kidney to ascend known as

Answer 22

Ectopic kidney

Question 23

What happens to renal arteries as kidneys ascend

Answer 23

• Existing renal arteries degenerate in sacral region

- As kidney moves upwards new renal arteries form

Question 24

When does kidney in embryo become functional

Answer 24

End of first trimester

Question 25

What happens to urine in embryo

Answer 25

Urine passed into amniotic cavity mixes with fluid Swallowed by foetus Passes through kidney and back into amniotic fluid

Question 26

What organ performs excretory functions in utero

Answer 26

Placenta (not kidney)

Question 27

Define kidney agenesis

Answer 27

Failure of kidney to form, often associated with uteric bud formation

Question 28

Is kidney agenesis common or rare

Answer 28

Fairly common (1 in 1000)

Question 29

What is bilateral agenesis

Answer 29

When both kidney fail to develop

Question 30

Can the baby survive after birth if it has bilateral agenesis

Answer 30

no

Question 31

What usually causes bilateral agenesis

Answer 31

Failure of uteric bud to form on both sides

Question 32

How many babies are born with bilateral agenesis

Answer 32

1 in 10,000

Question 33

As well as not having a kidneys, what other defects are associated with bilateral agenesis

Answer 33

Failure of lungs and club foot because no kidneys to produce amniotic fluid in the womb

Question 34

What is bifid ureter

Answer 34

Ureter splits in two

Question 35

What can be formed from bifid ureter

Answer 35

One large kidney with 2 ureters or two completely separate ureters

Question 36

Incidence of bifid ureters?

Answer 36

2%

Question 37

Does bifid ureter impact on kidney function

Answer 37

No

Question 38

What is ectopic-pelvic kidney

Answer 38

One kidney remains in pelvic, but still functional

Question 39

What is horseshoe kidney

Answer 39

Kidneys fuse in pelvic region forming a single U shaped kidney.

Question 40

Why can't horseshoe kidneys rise?

Answer 40

Due to position of inferior mesenteric artery

Question 41

Does horseshoe kidney function normally

Answer 41

Yes

Question 42

Incidence of ectopic kidney?

Answer 42

1 in 500 to 1 in 1290

Question 43

What % of ectopic kidneys are never detected

Answer 43

50

Question 44

What is polycystic kidney

Answer 44

Kidney develops fluid filled cysts

Question 45

What % of polycystic kidney patients have kidney failure by age 60

Answer 45

50

Question 46

How many people have autosomal dominant polycystic kidney

Answer 46

1: 1000

Question 47

How many people have autosomal recessive polycystic kidney

Answer 47

1: 20,000

Question 48

What % of mutations causing polycystic kidneys occur in polycystin/ PKD-1

Answer 48

85-90

Question 49

If the mutation of polycytic kidneys isn't in PKD-1, what is it?

Answer 49

Polycystin-2/ PKD-2

Question 50

Define primary cillia

Answer 50

Single sensory cilia on a cell

Question 51

Describe the sequence by which the cyst on the kidneys in polycystic kidney grows

Answer 51

- Cyst originates as dilations of intact tubule - Cyst enlarges and loses contact with nephron - Epithelium becomes secretory resulting in increased fluid secretion into lumen of cyst - Increased proliferation of cyst epithelium