Dominant polycystic kidney disease

Question 1

True or false: autosomal dominant is more common than recessive polycystic kidney disease?

Answer 1

True

Question 2

In PKD, the healthy kidney tissue is replaced with many f___-filled cysts

Answer 2

fluid

Question 3

The cysts can ____ blood vessels of neighbouring healthy nephrons and starve them of oxygen

Answer 3

compress

Question 4

The poor perfusion of the kidneys can activate the RAAS system causing fluid retention and ______

Answer 4

hypertension

Question 5

What does PKD lead to?

Answer 5

Renal failure

Question 6

The enlarged kidney in PKD may be _____ on examination of the abdomen

Answer 6

palpable

Question 7

Which genes are affected in autosomal dominant polycystic kidney disease?

Answer 7

PKD1 gene on chromosome 16
PKD2 gene on chromosome 4

Question 8

True or false: autosomal PKD normally is present from birth?

Answer 8

False
Normally manifests in adulthood

Question 9

In dominant PKD, there is lack of Polycystin 1 and 2 (PKD1 and PKD2) which is needed for inhibition of cell ____

Answer 9

proliferation

Question 10

What are extra-renal manifestations of PKD?

Answer 10

Cerebral aneurysms
Hepatic/ Splenic/ Pancreatic/ Ovarian/ Prostatic cysts
Mitral regurgitation
Colonic diverticula

Question 11

Why can PKD cause cerebral aneurysms?

Answer 11

Not completely understood

Thought to be abnormality in connective tissue and extracellular matrix. Affect structural integrity of blood vessels making them more prone to dilatation and formation of aneurysms.

PKD also leads to hypertension, increasing risk of formation and rupture of cerebral aneurysm.

Question 12

Why can PKD cause mitral regurgitation?

Answer 12

Not completely understood

Thought to be due to hypertension due to compression of renal blood vessels by cysts and activation of RAAS.
Chronic hypertrophy leads to left ventricular hypertrophy and dilation of left atrium, affecting structure and function of mitral valve.

Question 13

Why can PKD cause colonic diverticula?

Answer 13

Not completely understood.

PKD associated with abnormalities in connective tissue and extracellular matrix, may affect structural integrity of blood vessels and contribute to weakened areas in colonic wall so more likely to develop diverticula.

Question 14

What are complications of PKD?

Answer 14

Chronic loin/flank pain
Hypertension
Gross haematuria (cyst rupture)
Recurrent UTIs
Renal stones
ESRF

Question 15

Why are recurrent UTIs more likely with PKD?

Answer 15

Cysts in kidneys may alter normal flow of urine and create pockets or stasis where bacteria can accumulate.
may impede natural flushing of bacteria out of urinary system.
May require catheter use, increasing risk.

Question 16

How do you diagnose PKD?

Answer 16

USS
Genetic testing

Question 17

What medication can slow the development of cysts in autosomal dominant PKD?

Answer 17

Tolvaptan (vasopressin receptor agonist, slow development of cysts and progression of renal failure)

Question 18

Other than Tolvaptan, how can PKD be managed?

Answer 18

ACE inhibitors for antihypertensive
Analgesia
Antibiotics for infections
Drainage (aspiration/surgery)
Dialysis (for ESRF)
Renal transplant

Question 19

What other management steps can be taken for PKD?

Answer 19

Genetic counselling
Avoiding contact sports which increase risk of cyst rupture
Avoiding NSAIDs and anticoagulants
MR angiography for screening cerebral aneurysms.

Question 20

Why should NSAIDS be avoided in PKD?

Answer 20

NSAIDs inhibit prostaglandin formation and therefore inhibit their vasodilatory effects. Can decrease blood flow to kidneys, increasing risk of AKI.

NSAIDs associated with increased cyst rupture.

Can interfere with angiotensin II and cause sodium and water retention, possibly leading to fluid overload and worsening hypertension.

Question 21

Why should anticoagulants be avoided in PKD?

Answer 21

Some cysts are prone to bleeding and anti-coagulants increase risk of bleeding complications.