Polycystic Kidney Disease Flashcards
What are the two types?
Autosomal recessive
Autosomal dominant
Describe the genetics behind autosomal dominantPKD?
85% - mutation on chromosome 16 - PKD1
15% - mutation on chromosome 4 - PKD2
Which genetic abnormality is most likely to develop ESKD?
PKD1
What is the pathology behind ADPKD?
massive cyst enlargement leading to enlarged kidneys
epithelial lined cysts arise from a small population of renal tubules and spread all over the kidneys - cysts vary in size
MAINLY benign adenomas - some are malignant
What are the renal signs of ADPKD?
hypertension
reduced urine concentration ability
chronic pain - due to renal capsule stretching
haematuria - cyst rupture, cystitis, stones
cyst infection
renal failure
What are the extra renal signs of ADPKD?
liver cysts - 10 years after renal cysts ascites SOB pain intra-cranial aneurysms cardiac disease - valve prolapses diverticular disease hernias
How is ADPKD diagnosed?
ultrasound
renal enlargement
CT/MRI - only if unclear on USS
How is ADPKD managed?
control hypertension
hydration
proteinuria reduction
Toluaptan - carbonic anhydrase inhibitor - increases urination and reduces cyst volume and progression
What is the sign of ADPKD in children?
a single cyst in the first 10 years of life
What are the genetics behind autosomal recessive PKD?
chromosome 6
What are the characteristics of ARPKD?
young children
associated with hepatic lesions - fibrotic
bilateral renal involvement
symmetrical cysts
cysts appear from the collecting duct system
What are the signs of ARPKD?
kidney always palpable
hypertension
recurrent UTI
slow decline in GFR
What is the prognosis for ARPKD?
children who surive first year of life - 80% survival past 15 years
infants who survive the neonatal period - mortality rate of 9-24% in the first year of life
What is Alports syndrome?
hereditary nephritis - disorder of the type 4 collagen matrix
How is Alports syndrome inherited?
X linked
What is mutated in Alports syndrome? What does this cause?
COL4A5 gene
causes deficient collagenous matrix
What are the signs of Alports syndrome?
haemtauria
proteinuria - shows poor prognosis
What are the extra renal signs of Alports syndrome?
sensorinerual deafness
ocular defects
leiomyomatosis of oesophagus/genitals
How is Alports syndrome diagnosed?
renal biopsy - variable thickness GBM
haematuria and hearing loss
What is the treatment of Alports syndrome?
treat BP and proteinuria
dialysis/transplantation
What is Anderson Fabrys Disease?
error of the glycosphingolipid metabolism - deficiency of galactosidase A
lysosomal storage disease
How is Anderson Fabrys inherited?
X linked
How does Anderson Fabrys present?
renal failure cutaneous - angiokeratomas cardiomyopathy stroke pschcosis
How is Andersons Fabrys diagnosed?
plasma/leukocyte a-GAL activity
renal and skin biopsy
How is Andersons Fabrys treated?
fabryzyme replacement
What is medullary cystic disease?
autosomal dominant - morphologically abnormal renal tubules leading to fibrosis
normal/small kidneys
Where are the cysts in medullary cystic disease?
corticomedullary junction/medulla
they are unsymmetrical
How is medullary cystic disease diagnosed?
family history
CT scan
What is the treatment of medullary cystic disease?
renal transplantation
What is medullary sponge kidney?
dilation of the collecting ducts
cysts have calculi due to urinary stasis
How is medullary sponge kidney inherited?
sporadic
How is medullary sponge kidney diagnosed?
excretion urography - shows calculi
