Gastroenterology 6

Question 1

What are the intraluminal digestive defects which cause malabsorption?

Answer 1

	Carbohydrate intolerance
	Protein-energy malnutrition
	Cystic fibrosis
	Shwachman-Diamond syndrome (inherited bone marrow failure) 
	Chronic pancreatitis
	Cholestasis
	Pernicious anaemia
	Specific digestive enzyme deficiency- lipase

Question 2

What are the mucosal abnormalities which cause malabsorption?

Answer 2

 Coeliac disease
 Short bowel syndrome
 Dietary protein intolerance- milk protein allergy
 Intestinal infection or parasite- giardiasis
 IBD
 Abetalipoproteinaemia- disorder of lipid metabolism
 Protein-energy malnutrition, intestinal venous or lymphatic obstruction- congestive heart failure or intestinal lymphagiectasia

Question 3

What are the first line investigations for malabsorption?

Answer 3

o	FBC
o	U&E
o	Creatinine
o	Albumin
o	Total protein
o	Ca2+
o	Phosphate
o	LFT
o	Iron status
o	Coeliac antibody screen
o	Coagulation screen
o	Stool MC&S

Question 4

What are the further investigations for malabsorption?

Answer 4

o Upper GI endoscopy with biopsy for enteropathy
o Ileocolonscopy if features suggest colitis- ensure clotting is normal prior
o Sweat test- CF
o Immune function tests
o Faecal fat measurement & elastase
o Faecal alpha-1 anti-trypsin
o Exocrine pancreatic function tests

Question 5

What is the clinical presentation of parasitic infections?

Answer 5

o	Abdominal pain
o	Diarrhoea, dysentery, flatulence
o	Malabsorption & FTT
o	Abdominal distension
o	Intestinal obstruction
o	Biliary obstruction, liver disease
o	Pancreatitis
o	Fever

Question 6

What are the protozoa infections?

Answer 6

• Giardia lamblia- swallowed cysts develop into trophozoites that attach to the small intestinal villi causing mucosal damage
• Entamoeba histolytica
• Cryptosporidium- organism causes a mild self-limiting illness except in immunocompromised patients

Question 7

How does appendicitis present in children?

Answer 7

Anorexia
Vomiting
Abdo pain, central and colicky then localising to right iliac fossa (localised peritoneal inflammation)
Flushed face with oral fetor
Low grade fever
Abdominal pain aggravated by movement, e.g. on walking, coughing, jumping, bumps on the road during a car journey Persistent tenderness with guarding in the right iliac fossa (McBurney’s point).

Question 8

What is important to consider in preschool children with appendicitis?

Answer 8

The diagnosis is more difficult, particularly early in the disease
Faecoliths are more common and can be seen on a plain abdominal X­ray
Perforation may be rapid, as the omentum is less well developed and fails to surround the appendix, and the signs are easy to underestimate at this age.

Question 9

What is intussusception?

Answer 9

invagination of proximal bowel into a distal segment. It most commonly involves ileum passing into the caecum through the ileocaecal valve. Intussusception is the commonest cause of intestinal obstruction in infants after the neo­natal period. Although it may occur at any age, the peak age of presentation is between 3 months and 2 years.

Question 10

What is the most serious complication of intussusception?

Answer 10

Stretching and constriction of the mesentery resulting in venous obstruction, causing engorgement and bleeding from the bowel mucosa, fluid loss and subsequently bowel perforation, peritonitis and gut necrosis.

Question 11

How does intussusception present?

Answer 11

Paroxysmal, severe colicky pain and pallor (pale around mouth and draws legs up)
May refuse feeds, may vomit, which may become bile­stained depending on the site of the intussusception
• A sausage­ shaped mass – often palpable in the abdomen
• Passage of a characteristic redcurrant jelly stool comprising blood­stained mucus – this is a characteristic sign but tends to occur later in the illness and may be first seen after a rectal examination
• Abdominal distension and shock.

Question 12

What is the management for intussusception?

Answer 12

Fluid resuscitation to prevent shock
USS to confirm diagnosis
Rectal air insufflation by radiologist (no peritonitis) (75% success rate)
Surgery if this is unsuccessful

Question 13

What is Meckel diverticulum?

Answer 13

Around 2% of individuals have an ileal remnant of the vitello­intestinal duct, a Meckel diverticulum, which contains ectopic gastric mucosa or pancreatic tissue. Most are asymptomatic but they may present with severe rectal bleeding, which is classically neither bright red nor true melaena.
Can present with intussusception, volvulus, diverticulitis which mimics appendicitis.

Question 14

What is the management for Meckel’s diverticulum?

Answer 14

Technetium scam- increased uptake by ectopic gastric mucosa (70% of cases)
Surgical resection

Question 15

What is malrotation?

Answer 15

During rotation of the small bowel in fetal life, if the mesentery is not fixed at the duodenojejunal flexure or in the ileocaecal region, its base is shorter than normal, and is predisposed to volvulus. Ladd bands may cross the duodenum, contributing to bowel obstruction
Presents as:
Obstruction
• Obstruction with a compromised blood supply.

Question 16

How does malrotation present?

Answer 16

Obstruction with bilious vomiting is the usual presen­tation in the first few days of life
Abdominal pain and tenderness from peritonitis or ischaemic bowel
Any child with dark green vomiting needs an urgent upper GI contrast study
Treated with laparotomy

Question 17

Which clinical features can show the pathogen in gastroenteritis?

Answer 17

Campylobacter jejuni infection, the commonest of the bacterial infections in developed countries, is often associated with severe abdominal pain. Shigella and some salmonellae produce a dys­enteric type of infection, with blood and pus in the stool, pain and tenesmus. Shigella may be accompa­nied by high fever. Cholera and enterotoxigenic E. coli infection are associated with profuse, rapidly
dehydrating diarrhoea.

Question 18

Why aren’t antidiarrhoea drugs used in gastroenteritis?

Answer 18

are ineffective
• may prolong the excretion of bacteria in stools
can be associated with side­effects
• add unnecessarily to cost
• focus attention away from oral rehydration.

Question 19

When are antibiotics indicated in gastroenteritis?

Answer 19

suspected or confirmed sepsis, extra­intestinal spread of bacterial infection, for sal­monella gastroenteritis if <6 months old, in malnour­ished or immunocompromised children or for specific bacterial or protozoal infections (e.g. Clostridium difficile­ associated with pseudomembranous colitis, cholera, shigellosis, giardiasis).

Question 20

What is post-gastroenteritis syndrome?

Answer 20

Introduction of normal diet causes a watery diarrhoea
Temporary lactose intolerance- confirmed by +ve clinitest result (non-absorbed sugar in stool)
Oral rehydration solution for 24hr then back to normal diet

Question 21

What are the causes of nutrient malabsorption?

Answer 21

Cholestatic liver disease or biliary atresia
Lymphatic leakage or obstruction
Short bowel syndrome (congenital or necrotising enterocolitis)
Loss of terminal ilea functioning (resection, crohn)
Exocrine pancreatic dysfunction (CF)
Small intestinal mucosal disease (coeliac, enzyme defects)