Gastroenterology

Question 1

Hepatic diverticulum arises from?

Answer 1

Arises from the foregut, cranial to the pancreatic duct at 3 weeks

Question 2

What is the pathogenesis of biliary atresia

Answer 2

Gall bladder duct becomes solid in early development and failure of recanalisation (not failure to rotate) leads to biliary atresia

Question 3

Where are Kupffer cells derived from

Answer 3

The bone marrow. They invade the liver and line the sinusoids. At 10 weeks, the liver has started to form blood cells

Question 4

Hepatitis A

Answer 4

highly contagious transmitted by faecal-oral route.
Incubation period 3 weeks. Lymphadenopathy and splenomegaly may occur. Diagnosis via Hepatitis A IgM positive, though stool and blood PCR

Question 5

Meckel’s diverticulum

Answer 5

common cause of significant GI bleeding in young children, with 60% of cases presenting before the age of two years. Bleeding is caused by erosion of intestinal mucosa from ectopic gastric mucosa, which is found within the MD in 25% of cases. This ectopic mucosa can be detected by Technecium-99m scan (“Meckels Scan.”)

Question 6

Juvenille polyps

Answer 6

one of the most common causes of significant PR bleeding in children, with peak presentation at 3-4 years of age. Juvenile polyps are most often pedunculated hamartomas, which can be both diagnosed and removed during colonoscopy.

Question 7

Salmonella enteritidis (nontyphoidal Salmonella)

Answer 7

food-borne infection (eggs and egg containing products). 8-72 hrs within eating contaminated food or water

Gastro: N/V, fever, diarrhoea, cramping

<5% develop bacteraemia - lead to variety of extra-intestinal manifestations e.g. endocarditis, mycotic aneurysm, osteomyelitis

Salmonella meningitis feared complication with high case fatality rate than occurs primarily in infants

Tx if required
- IV ceftriaxone. cefotaxime
- PO ciprofloxacin or cotrimoxazole

Question 8

A four-year-old boy is referred to you for investigation of persistent diarrhoea and poor weight gain. The following results are obtained: haemoglobin (Hb) 100 g/L [110-150]; mean corpuscular volume (MCV) 70 fL [75-90]; total serum IgA 0.07 g/L [1.23-2.32]; antigliadin-IgG 88 U/L [<50]; antigliadin-IgA 0 U/L [<25]; anti-endomysial antibody negative. Which of the following is the most appropriate next step in management?

Answer 8

In this patient, antigliadin IgA, and anti-endomysial (also IgA) antibody are both negative, but this is in association with low levels of total serum IgA. Elevated antigliadin IgG.

He should have a small bowel biopsy. This is particularly because the IgG anti-gliadin antibody test has a lower specificity (frequent false positives).

Tissue transglutaminase (tTG) is an IgA antibody, therefore dependent on normal IgA levels.