Urinary development

Question 1

Oligohydramnios

Answer 1

Renal agenesis - when the ureteric bud fails to meet the metanephric blastema results in absense of kidneys
As a result fetuses can’t make enough amniotic fluid - Oligohydramnios - and fetus is confined to an abnormally small amniotic sac
Potter sequence - deformed limbs, wrinkly, dry skin and abnormal face

Question 2

Pelvic kidney

Answer 2

When the kidneys do not ascend at all, and remain in the pelvis
Adrenal glands are in the same location reflecting their different embryology cal origin

Question 3

Horseshoe kidney

Answer 3

If the metanephric blastema are positioned more medially before ascent, the two kidneys may fuse at the midline
Forms a horseshoe shaped kidney crossing over the anterior surface of the aorta
The kidney becomes caught under the inferior mesenteric artery during ascent, but can still function as normal

Question 4

Congenital polycystic kidney disease

Answer 4

Presumably due to defects in tubule growth and failure of nephrons to fuse with collecting tubules
The nephrons are functional so form large fluid-filled cysts
Patients require dialysis or kidney transplantation

Question 5

Bifid ureter

Answer 5

If ureteric bud bifurcated early on as it enters the metanephric blastema, it can form a partial bifid ureter.
Sometimes they may have lobes in common or could be divided separately into two parts, each with a separate pelvis and ureter.
Asynchronous contractions –> urine reflex between branches
Predisposes individuals to urinary tract infections due to stagnant urine within the ureters