Dominant polycystic kidney disease Flashcards
True or false: autosomal dominant is more common than recessive polycystic kidney disease?
True
In PKD, the healthy kidney tissue is replaced with many f___-filled cysts
fluid
The cysts can ____ blood vessels of neighbouring healthy nephrons and starve them of oxygen
compress
The poor perfusion of the kidneys can activate the RAAS system causing fluid retention and ______
hypertension
What does PKD lead to?
Renal failure
The enlarged kidney in PKD may be _____ on examination of the abdomen
palpable
Which genes are affected in autosomal dominant polycystic kidney disease?
PKD1 gene on chromosome 16
PKD2 gene on chromosome 4
True or false: autosomal PKD normally is present from birth?
False
Normally manifests in adulthood
In dominant PKD, there is lack of Polycystin 1 and 2 (PKD1 and PKD2) which is needed for inhibition of cell ____
proliferation
What are extra-renal manifestations of PKD?
Cerebral aneurysms
Hepatic/ Splenic/ Pancreatic/ Ovarian/ Prostatic cysts
Mitral regurgitation
Colonic diverticula
Why can PKD cause cerebral aneurysms?
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.
Why can PKD cause mitral regurgitation?
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.
Why can PKD cause colonic diverticula?
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.
What are complications of PKD?
Chronic loin/flank pain
Hypertension
Gross haematuria (cyst rupture)
Recurrent UTIs
Renal stones
ESRF
Why are recurrent UTIs more likely with PKD?
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.
How do you diagnose PKD?
USS
Genetic testing
What medication can slow the development of cysts in autosomal dominant PKD?
Tolvaptan (vasopressin receptor agonist, slow development of cysts and progression of renal failure)
Other than Tolvaptan, how can PKD be managed?
ACE inhibitors for antihypertensive
Analgesia
Antibiotics for infections
Drainage (aspiration/surgery)
Dialysis (for ESRF)
Renal transplant
What other management steps can be taken for PKD?
Genetic counselling
Avoiding contact sports which increase risk of cyst rupture
Avoiding NSAIDs and anticoagulants
MR angiography for screening cerebral aneurysms.
Why should NSAIDS be avoided in PKD?
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.
Why should anticoagulants be avoided in PKD?
Some cysts are prone to bleeding and anti-coagulants increase risk of bleeding complications.
