GI Abnormalities

Question 1

What is Hirschsprung’s disease?

Answer 1

Congenital absence of ganglia in a segment of the colon (rarely long segment disease all the way to the stomach). This causes functional GI obstruction, constipation and megacolon.

Usually present with failure or delay to pass meconium

Question 2

What complications can occur as a result of Hirschsprung’s disease?

Answer 2

Perforation
Bleeding
Ulcers
Enterocolitis
Short gut syndrome

Question 3

How should suspected Hirschsprung’s disease be investigated?

Answer 3

Faeces may be felt in the abdomen and PR exam will reveal a tight anal sphincter and explosive faecal and gas discharge.

Rectal suction biopsy of the aganglionic section. Staining for acetylcholinesterase positive nerve excess is more accurate. (full thickness rectal biopsy)

Question 4

How should Hirschsprung’s disease be managed?

Answer 4

Initial management is bowel irrigation until diagnosis is confirmed
Removal of the aganglionic segment with or without a colostomy (anorectal pull through)

Question 5

What are the 2 most important risk factors for Hirschsprng’s disease?

Answer 5

Male

Down’s syndrome

Question 6

What is oesophageal atresia and trachea-oeopshageal fistula?

Answer 6

Spectrum of disorders but usually occurring together. Upper oesophagus ends in a blind sack and there is a connection between the trachea and lower oesophagus.

Question 7

What clinical features are there for oeopshagela atresia and trachea-oesophageal fistula?

Answer 7

Polyhydramnios
Small stomach
Cough
Airway obstruction
Increased secretions
Blowing bubbles
Distended abdomen
Cyanosis
Aspiration
Inability to pass NG tube with x-ray showing it coiled up in the oesophagus

Question 8

How is oesophageal atresia and trachea-oesopahgeal fistula managed?

Answer 8

Stop feeding
Suck out oesophageal pouch
Primary surgical repair
But half will have other anomalies

Question 9

What is a congenital diaphragmatic hernia?

Answer 9

Defect in the diaphragm allows the abdominal organs into the thoracic cavity impeding lung development

Question 10

How is a diaphragmatic hernia diagnosed?

Answer 10

Diagnosis can be made antenatally by US or postnatally via CXR

Question 11

What effect does a congenital diaphragmatic hernia have on the development of the lungs?

Answer 11

Causes impaired lung development hypoplasia and pulmonary hypertension

Question 12

What features might suggest a congential diaphragmatic hernia?

Answer 12

Difficult resuscitation at birth
Respiratory distress
Bowel sounds in hemithorax
Can be associated with neural tube defects, trisomy 18 and some chromosome deletions

Question 13

How is congenital diaphragmatic hernia managed?

Answer 13

Prenatal
Referral to tertiary centre for foetal surgery - Tracheal obstruction by balloon may encourage lung growth but can cause prematurity.

Postnatal
Insert large bore naso gastric tube when diagnosis suspected to keep all air out of the gut.
Ventilate and paralyse as soon as born then surgery should follow at an appropriate centre.

Question 14

What are inguinal hernias?

Answer 14

Occurring due to patent processus vaginalis. Hernia implies bowel involvement. Hydrocele if only fluid from the peritoneal cavity is present.

Question 15

When are interventions required on hydroceles?

Answer 15

Hydrocele usually sort themselves out and intervention should only occur if persistent to age of 2 or more.

Question 16

What are the clinical features of inguinal hernias?

Answer 16

Bulge lateral to the pubic tubercle during crying
Occur in boys 5 times more than girls
Usually on the right but can be left or bilateral
Hydrocele present in 19%

Question 17

How are inguinal hernias managed?

Answer 17

Surgical repair 
6 by 2 rules 
<6weeks operate within 2 days 
<6months operate within 2 weeks 
<6years operate within 2 months

Question 18

When should umbilical hernias be operated on?

Answer 18

Note umbilical hernia are common, complications are rare and usually resolve by ages 2-3. These should not be operated on until after 3 years of age if large and symptomatic or 5 years if asymptomatic and small.

Question 19

What is an imperforate anus?

Answer 19

Covering over the anal canal meaning faeces can’t exit.

Babies usually have an associated fistula. In boys this is a posterior urethral fistula in girls this is a posterior fourchette fistula. Absence of a perineal fistula in boys suggests communication with the urethra and so colostomy will be required.

GU imaging should be done to look for other abnormalities.

Question 20

Which syndrome is associated with imperforate anus?

Answer 20

Trisomy 21 commonly have imperforate anus without a fistula.

Question 21

How do mid-gut malrotations usually present?

Answer 21

Commonly this presents with bilious vomiting due to the absent attachment of the small intestines’ mesentery causing mid gut volvulus or obstruction of the third part of the duodenum. Usually 3-7 days after birth, volvulus with compromised circulation may result in peritoneal signs and haemodynamic instability.

Clinical Features
No meconium 
Abdominal pain 
Constipation 
Passage of blood indicates necrosis

Question 22

How are mid-gut malrotations repaired?

Answer 22

Surgical repair - Ladd’s procedure

Question 23

How are mid-gut malrotations diagnosed?

Answer 23

Upper GI contrast study – shows DJ flexure is more medially placed
USS shows abnormal orientation of SMA and SMV

Question 24

What is a gastroschisis?

Answer 24

Paraumbilical defect with extrusion of abdominal contents. Usually diagnosed antenatally

Question 25

What are the risk factors for a gastroschisis?

Answer 25

Many pregnancies
Young parents
New father

Question 26

How is Gastroschisis managed?

Answer 26

Cover in clingfilm once born and keep baby warm hydrated and aim to surgically repair as soon as possible. May require a staged procedure involving a silo as the abdomen will be too small at first for everything to fit in.

TPN may be required for multiple weeks as it takes a while for function to return

Question 27

What is an exomphalos?

Answer 27

Defect of the umbilical ring causing herniation of abdominal viscera covered in peritoneum. Small example may only contain Meckel’s diverticulum whilst larger may contain stomach, liver and bladder etc. Again abdominal cavity likely to be small and contents can’t fit.

Question 28

How is Exaomphalos and Gastroschisis diagnosed?

Answer 28

Diagnosed antenatally via scan, AFP likely to be raised too.

Question 29

How is Exomphalos managed?

Answer 29

Protect herniated viscera and keep baby warm hydrated, maintain electrolytes, prevent hypothermia. Aim to surgically repair as soon as possible. May require a staged procedure involving a silo as the abdomen will be too small at first for everything to fit in.
TPN may be required for multiple weeks as it takes a while for GI function to return
May lead to respiratory distress due to reduced volume of abdominal cavity.

Question 30

What is Meckel’s diverticulum?

Answer 30

A congenital diverticulum of the small intestine. It is a remnant of the omphalomesenteric duct (also called the vitellointestinal duct) and contains ectopic ileal, gastric or pancreatic mucosa. Normally, in the foetus, there is an attachment between the vitellointestinal duct and the yolk sac. This disappears at 6 weeks gestation.

Question 31

What are the rule of 2’s in Meckle’s diverticulum?

Answer 31

Rule of 2s
occurs in 2% of the population
• is 2 feet from the ileocaecal valve
• is 2 inches long

Question 32

How does meckel’s diverticulum usually present?

Answer 32

Presentation (usually asymptomatic)
• abdominal pain mimicking appendicitis
• rectal bleeding
• Meckel’s diverticulum is the most common cause of painless massive GI bleeding requiring a transfusion in children between the ages of 1 and 2 years
• Intestinal obstruction – secondary to an omphalomesenteric band (most commonly), volvulus and intussusception

Question 33

What is the management of meckel’s diverticulum?

Answer 33

Removal if narrow neck or symptomatic. Options are between wedge excision or formal small bowel resection and anastomosis.

Question 34

What causes jejunal/ileal atresia

Answer 34

Occurs due to vascular insufficiency in utero 1 in 3000

Question 35

How does jejunal/ileal atresia present?

Answer 35

Presents with obstruction and bilious vomiting in neonates usually within 24 hours of birth

Question 36

How are Jejunal/ileal atresia diagnosed?

Answer 36

AXR shows air-fluid levels

Question 37

How are jejunal/ileal atresia managed?

Answer 37

Surgery – laparotomy with primary resection and anastomosis