9: Inherited renal disorders

Question 1

What is the most common mode of inheritance of polycystic kidney disease?

Answer 1

Autosomal dominant

Question 2

What mutations cause autosomal dominant polycystic disease?

Which chromosome is involved?

Answer 2

PKD1 on chromosome 16

PKD2 on chromosome 4

Question 3

Which gene mutation most commonly causes autosomal dominant PKD?

Answer 3

PKD1 on chromosome 16

Question 4

Which mutation, causing autosomal dominant PKD, carries the worst prognosis?

Answer 4

PKD1 (chromosome 16)

Question 5

What is the long-term consequence of untreated PKD?

Answer 5

Kidney failure

Question 6

What happens in PKD?

Answer 6

Epithelium of renal tubules forms enlarged cysts

Question 7

Is ADPKD unilateral or bilateral?

Answer 7

Bilateral

Question 8

In PKD, the kidneys (increase / decrease) in size.

Answer 8

kidneys enlarge

Question 9

What can occur in the epithelium in ADPKD?

Answer 9

Neoplasia

Question 10

What are the symptoms of ADPKD?

Answer 10

Chronic loin pain

Dilute urine (Loops buggered so can’t concentrate it)

Haematuria

Hypertension (SEN)

Question 11

What causes haematuria in PKD?

Answer 11

Rupture of cysts

Inflammation

Renal calculi

Question 12

Cysts of which organ may be found alongside PKD?

Answer 12

Liver

Question 13

What happens to

a) kidney function
b) liver function (if affected)

in ADPKD?

Answer 13

a) eGFR decreases

b) Liver function generally preserved

Question 14

ADPKD has a lot of ___ manifestations.

Answer 14

systemic

liver, brain (stroke), cardiac (valve disease), GI (diverticulitis, hernia…)

Question 15

Which imaging method is used to view the kidneys in ADPKD?

Answer 15

Ultrasound

Question 16

How long are the kidneys normally?

Answer 16

10 - 12 cm

Any more than this e.g in ADPKD is abnormal

Question 17

If an USS for cysts is inconclusive, what scan would you do?

Answer 17

MRI scan

Question 18

What is the percentage chance of your child inheriting ADPKD?

Answer 18

50%

As with all autosomal dominant disease

Question 19

How is ADPKD treated?

Answer 19

Control symptoms: hypertension, dehydration, ?proteinuria

Experimental drugs

Renal replacement therapy

Question 20

What experimental drug is used to reduce cyst volume and progression?

What are the criteria for using it?

Answer 20

Tolvaptan

eGFR < 60, renal volume > 700mls

Question 21

What are complications of ADPKD which need to be treated as they arise?

Answer 21

Haemorrhage

Infection

Question 22

When is dialysis indicated?

Answer 22

GFR < 15

Question 23

What is the rare type of polycystic kidney disease, commonly found in children?

Answer 23

Autosomal recessive PKD

Question 24

Which chromosome mutates in ARPKD?

Answer 24

Chromosome 6

Question 25

What part of the kidneys is affected by **ARPKD**?

Answer 25

**Collecting ducts** vs renal tubules in ADPKD

Question 26

What slowly declines in ARPKD?

Answer 26

**GFR** From birth So generally fatal

Question 27

What syndrome presents with **protein/****haematuria, hearing loss**and**eye problems**?

Answer 27

**Alport syndrome**

Question 28

What is the mode of inheritance of **Alport syndrome**?

Answer 28

**X-linked**

Question 29

What protein is abnormal in Alport syndrome?

Answer 29

**Type IV collagen** don't confuse with goodpasture's

Question 30

What are the a) renal b) extra-renal symptoms of Alport syndrome?

Answer 30

**a) Haematuria**, then **proteinuria** ## Footnote **b) Sensorineural HL, eye problems**

Question 31

How is **Alport syndrome** investigated?

Answer 31

**Renal biopsy** for abnormal GBM (Type IV collagen)

Question 32

How is **Alport syndrome** treated?

Answer 32

**Control of proteinuria** - antihypertensives, diabetes ## Footnote **Renal replacement therapy**

Question 33

What is a rare X-linked condition causing **renal, liver** and **lung** problems? What type of disease is it?

Answer 33

**Anderson Fabry's disease** Metabolic disease

Question 34

Which enzyme is defective in Anderson Fabry's disease?

Answer 34

**Alpha-galactosidase 1**

Question 35

How is **Fabry's disease** treated?

Answer 35

**Enzyme replacement** (fabryzyme)

Question 36

What is the difference between **polycystic kidney** **disease** and **medullary cystic kidney disease**?

Answer 36

**MCKD** - renal tubules FIBROSE so kidneys get SMALLER **PKD** - cysts, kidneys get bigger

Question 37

How do the kidneys change in size in a) medullary cystic kidney disease b) polycystic kidney disease?

Answer 37

**a) Smaller** **b) Bigger**

Question 38

How is **medullary cystic kidney disease** treated?

Answer 38

**Kidney transplant**

Question 39

medullary sponge kidney

Question 40

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