Inherited Diseases of the Kidney

Question 1

What are the 2 forms of inheritance of polycystic kidney disease?

Answer 1

Autosomal recessive

Autosomal dominant

Question 2

Which is more common, ADPKD or ARPKD?

Answer 2

ADPKD

Question 3

What are the 2 gene mutations and the chromosomes that they appear on that can lead to ADPKD? Which is most common?

Answer 3

PKD gene 1 - Chr 16 - most common 85%

PKD gene 2 - Chr 4 - 15%

Question 4

Which PKD1 or PKD2 patients develop ESRF earlier?

Answer 4

PKD1

Question 5

What pathologies occur in ADPKD on the kidneys?

Answer 5

Massive cyst enlargement
Massive kidneys
Epithelial lined cysts arise from a small population of renal tubules
Benign adenomas

Question 6

How des ADPKD present?

Answer 6

Reduced urine concentrating ability 
Chronic pain 
HTN 
Haematuria 
cyst infection 
Renal failure

Question 7

What are the extra-renal manifestations of ADPKD and which is most common?

Answer 7

Hepatic cysts - most common 
Intra-cranial aneurysm - uncommon 
Cardiac disease 
Diverticular disease 
Hernias

Question 8

What are the 1st and 2nd line radiological techniques for diagnosing ADPKD?

Answer 8

1st - US

2nd - Ct or MRI when US is unclear

Question 9

ADPKD in children presents when?

Answer 9

In utero or first year of life

Question 10

What suggests ARPKD rather than ADPKD in children?

Answer 10

US suggestion of congenita hepatic fibrosis suggests ARPKD

Question 11

How is ADPKD managed?

Answer 11

HTN rigorously controlled 
Hydration 
Proteinuria reduction 
Dialysis 
Renal transplant

Question 12

What are the complications of ADPKD?

Answer 12

Cyst haemorrhage
Cyst infection
Renal failure

Question 13

ARPKD is always associated with what?

Answer 13

hepatic lesions

Question 14

What gene is responsible for ARPKD and where is it?

Answer 14

PKHD1 on Chr 6

Question 15

How does ARPKD present histologically?

Answer 15

Cysts are seen appearing from the collecting duct system

Question 16

How does ARPKD present clinically?

Answer 16

Varies 
Kidneys always palpable 
HTN 
Recurrent UTIs 
Slow delcine in GFR

Question 17

What is the other term for Alport’s Syndrome?

Answer 17

Hereditary Nephritis

Question 18

How is Alport’s syndrome inherited?

Answer 18

X-linked inheritance

Question 19

What causes Alport’s syndrome?

Answer 19

Mutation in the COL4A5 gene eads to deficient collagenous matrix

Question 20

What is the characteristic feature of Alport’s syndrome and how else may it present?

Answer 20

Haematuria - characteristic feature
Proteinuria - seen later but confers bad prognosis
SNHL
Ocular defects
Leiomyomatosis of oesophagus/ genitalia - rare

Question 21

On renal biopsy what is seen in Alport’s syndrome?

Answer 21

variable thickness GBM and splitting of the lamina densa

Question 22

Anderson Fabry’s disease is what?

Answer 22

Inborn error of glycosphingolipid metabolism (deficiency of a-galactosidase A)
X-linked lysosomal storage disease

Question 23

Where does Anderson Fabry’s disease present?

Answer 23

Kidneys
Liver
Lungs
Erythrocytes

Question 24

How is a diagnosis of Anderson Fabry’s disease made?

Answer 24

Plasma/ leukocyte a-GAL activity
Renal biopsy - concentric lamellar inclusion within lysosomes
Skin biopsy

Question 25

What is the skin condition seen in Anderson Fabry’s disease?

Answer 25

Cutaneous-Angiokeratoma’s

Question 26

How is Medullary cystic kidney inherited?

Answer 26

Autosomal dominant inheritance

Question 27

Macroscopically describe Medullary cystic kidney?

Answer 27

Cortex and edulla are both shrunken

Presence of irregularly distributed cysts of variable size at the corticomedullary junction and in the outer medulla

Question 28

Treatment mechanism for meduallary cystic kidney?

Answer 28

Renal transplant

Question 29

What is Medullary sponge kidney?

Answer 29

Dilation of the collecting ducts whihc can lead in severe cases to the meduallary appearing like a sponge
Uncommon
Sporadic inheritance