Cystic Kidney Disease B&B

Question 1

what is the cause of multicystic dysplastic kidney?

Answer 1

Spontaneous/non-inherited abnormal ureteric bud-mesenchyme interaction —> kidney replaced with cysts, no/little functioning renal tissue, absent ureter

unilateral or bilateral (—> Potter’s)

Question 2

What occurs in unilateral versus bilateral multicystic dysplastic kidney?

Answer 2

Multicystic, dysplastic kidney: kidney replaced with cysts (non-inherited)

Unilateral —> other kidney hypertrophies
bilateral —> Potter’s syndrome (oligohydramnios, not compatible with life)

Question 3

What are the two genetic ways in which polycystic kidney disease presents?

Answer 3

autosomal recessive – presents in infants

Autosomal dominant – presents in young adults

Question 4

How does autosomal recessive polycystic kidney disease present?

Answer 4

ARPKD (“juvenile”): occurs in infants, presents with high blood pressure and renal failure, can occur with Potter’s syndrome

Associated with liver disease (fibrosis/cysts) and can cause portal hypertension (ascites)

Question 5

how does autosomal dominant polycystic kidney disease present?

Answer 5

ADPKD (AD = ADult): mutation in APKD1/2 genes —> microscopic cysts present at birth and develop over many years, symptoms occur in adults (high blood pressure, hematuria, renal failure)

Associated with berry aneurysm, liver cyst, mitral valve prolapse

Question 6

Pt is a 23yo M presenting with high blood pressure, hematuria and signs of renal failure. FHx is significant for sudden death from a berry aneurysm. What is likely going on?

Answer 6

autosomal dominant polycystic kidney disease: microscopic cysts present at birth and develop over many years, symptoms occur in adults (high blood pressure via RAAS, hematuria, renal failure)

Associated with berry aneurysm, liver cyst, mitral valve prolapse

Question 7

what is associated with autosomal recessive versus autosomal dominant polycystic kidney disease?

Answer 7

Autosomal recessive (presentation in children): liver fibrosis/cysts, portal hypertension (ascites)

Autosomal dominant (presentation in adults): berry aneurysm (subarachnoid hemorrhage), liver cysts, mitral valve prolapse

Question 8

How does medullary cystic kidney disease present?

Answer 8

autosomal dominant, cysts in collecting ducts of medulla

Kidney fibrosis —> small/shrunken kidneys —> renal failure

Often early onset (adolescent) gout

Question 9

How does the size of the kidneys compare in polycystic kidney disease vs medullary cystic kidney disease?

Answer 9

polycystic KD: enlarged kidneys due to cysts

medullary cystic KD: shrunken kidneys due to fibrosis

Question 10

which of the following cystic kidney diseases is usually unilateral? Why does this make sense?
a. Multicystic dysplastic
b. Polycystic kidney disease.
c. Medullary cystic.

Answer 10

a. Multicystic dysplastic - usually unilateral, which makes sense because development is spontaneous/non-inherited

Question 11

which of the following cystic kidney diseases is associated with berry aneurysms?
a. Multicystic dysplastic
b. AR Polycystic kidney disease.
c. AD Polycystic kidney disease.
d. Medullary cystic.

Answer 11

c. AD Polycystic kidney disease - presents bilaterally in adults, large kidneys due to cysts