Paediatric Gastroenterology 2

Question 1

What gene/gene product is associated with Crigler-Najjar Syndrome/Gilbert syndrome?

Answer 1

UGT1A1 - Glucuronyl Transferase

• AR complete deficiency in Crigler Najjar Type 1, high risk kernicterus, partial in Type 2

Question 2

How common is Gilbert Syndrome?

Answer 2

2-10%

Question 3

Where is the gene associated with Wilson Disease located?

Answer 3

Chromosome 13q14.3 encoding ATP7B

Question 4

The SERPINA1 gene is associated with which disease?

Answer 4

Alpha-1 -antitrypsin deficiency

• Normal is the PiMM phenotype
• Liver disease is the PiZZ phenotype (misfolding causes hepatocyte death and increased asthma but not emphysema)
• Lung emphysema is the ‘null’ type

Question 5

What are the key features of primary familial intrahepatic cholestasis?

Answer 5

• PFIC 1 - <1, normal GGT, very itchy, modest ALT/AST rise
• PFIC 2 - neonatal, normal GGT, very itchy, neonatal hepatitis
• PFIC 3 - variable age and presentation, very high GGT

Question 6

What genes are associated with PFIC?

Answer 6

• FIC1 encodes Atp8b1
• BSEP encodes ABCB11
• MDR3 encodes ABDB4

Question 7

The most common causes of secondary sclerosing cholangitis in children are….

Answer 7

Langerhans cell histiocytosis and primary immunodeficiency.

Question 8

How does omeprazole work to reduce acid secretion?

Answer 8

Binds to the hydrogen potassium ATPase pump.

Question 9

What commonly ingested compounds affect (decrease) absorption of thyroxine?

Answer 9

Iron salts, antacids, milk, calcium carbonate, cholestyramine - all bind to it

Question 10

How does wet/dry beriberi present?

Answer 10

• Thiamine deficiency (B1)
• Wet=CHF, tachycardia and oedema
• Dry=neuritis, parasthaesia, irritability, anorexia

Question 11

How does pellagra present?

Answer 11

• Niacin deficiency (B3)
• Niacin for Neuro - encephalopathy + dementia, peripheral neuropathy, apathy, anorexia, diarrhoea with mucosal atrophy, dermatitis

Question 12

If you see a child with glossitis, chelitis, complaining of visual change and eye pain, and also has dermatitis…

Answer 12

• think Riboflavin (B2) for Retina
• photophobia, loss of VA, burning/itching eyes, corneal vascularisation
• glossitis, chelitis
• seborrheic dermatitis

Differentiate from Pyridoxine (B6) and Biotin deficiency by eyes
Pyridoxine also has more stomatitis, anaemia, irritability, seizure
Biotin affects hair, more nausea/anorexia/insomnia and muscle pain

Question 13

What are ApoA and ApoB associated with?

Answer 13

ApoA = HDL
ApoB = chylomicrons, VLDL, LDL

Question 14

Match the gene and the syndrome:

• SPINK1
• NOTCH2
• STK11
• RET
• UGTP81

Answer 14

• Familial pancreatitis
• Alagille syndrome
• Peutz-Jeghers syndrome
• Hirschsprungs
• Gilberts syndrome

Question 15

How does MMF work?

Answer 15

• Inhibits synthesis of guanosine monophosphate nucleotides

- blocks purine synthesis, preventing proliferation of T and B cells

Question 16

NOD2 is associated with which disease?

Answer 16

Crohn’s

Question 17

JAG1 is associated with which disease?

Answer 17

Alagille

Question 18

Which disease is MYO5B associated with?

Answer 18

Microvillus atrophy

Question 19

Where is folate mostly absorbed?

Answer 19

Jejeunum