Intussusception - GM

Question 1

define intussusception

Answer 1

paediatric emergency that occurs when a section of bowel telescopes into its neighbouring distal section, causing bowel obstruction

Question 2

most common siite for intussuscption

Answer 2

ileocaecal valve (ileocolic intussusception)

Question 3

if left untreated, intussusception may cause

Answer 3

serious complications including bowel necrosis, perforation and peritonitis

Question 4

aetiology

Answer 4

usually no clear cause
can be associated with a preceding infection
may occur due to a large peyer’s patch acting as a lead point
may occur due to an abnormal area acting as a lead point (pathological lead point)

Question 5

what is a pathological lead point

Answer 5

an area of abnormal bowel that is caught and pulled by peristalsis, leading to intussusception

Question 6

intussusception caused by a pathological lead point is more likely in

Answer 6

patients presenting outside of the typical age range or where intussusception occurs away from the ileocaecal valve

Question 7

examples of pathological lead points and other secondary causes:

Answer 7

meckel’s diverticula (and other congenital bowel defects)
intestinal polyps
lymphomas and leukaemias
hence-schonlein pupura HSP

Question 8

risk factors for intussusception

Answer 8

most common in ages 4-18 months and slightly more common in boys

Question 9

triad of symptoms

Answer 9

• intermittent, severe abdominal pain, may present as screaming episodes in which the child is inconsolable and draws their knees up to their chest
• vomiting, becomes bilious in later stages when bowel obstruction occurs
• redcurrant jelly stool: a late feature that occurs with ischaemic mucosa tissue is sloughed off and is excreted in the stool, mixed with blood and mucous

Question 10

other symptoms of intussusception

Answer 10

child may appear well between screaming episodes but will become lethargic over time as dehydration worsens
odd posturing which may be mistaken for seizure activity
other features of dehydration eg. sunken eyes, dry lips

Question 11

hallmark sign of intussusception O/E

Answer 11

a sausage-shaped mass palpable in the right upper quadrant of the abdomen

Question 12

other signs of intussusception O/E

Answer 12

tenderness, reduced/absent bowel sounds, distension (secondary to bowel obstruction) and, in the late stages, pertonitis, (secondary to perforation)

Question 13

differential of intussusception

Answer 13

constipation
gastroenteritis
malrotation volvulus
incarcerated hernia
adhesional bowel obstruction
testicular torsion
appendicitis

Question 14

relevant bedside investigations

Answer 14

basic observations (vital signs): especially heart rate and blood pressure, which may be abnormal if the child is dehydrated and unwell
capillary blood gas; significant acid-base disturbances can be present in severely unwell children with intussusception
urinalysis: evidence of UTI, which is a differential cause of abdo pain
stook sample for microscopy, culture and sensitivieties: to look for evidence of gastroentertitis

Question 15

laboritory investigations

Answer 15

full blood count: neutrohlia may be present in later stages
urea and electrolytes: dehydration and vomiting may cause electrolyte disturbances
LFTs: to exclude hepatoibiliary causes
CRP: may be elevated in later stages

Question 16

ultrasound

Answer 16

gold standrad investigation
classically shows a ‘target sign’

Question 17

abdominal x-ray

Answer 17

less sensitive and specific than US
may show typical picture of bowel obstruction, with distended proximl loops of bowel and paucity of distal bowel gas

Question 18

initial management

Answer 18

prompt and adequate fluid resuscitation is vital for the management of intussusception and failure to instigate this early is one of the main causes of mortality in intussusception
also:
- analgesia, IV paracetamol or opoiods
- NGT to decompress stomach
- make child nil by mouth

Question 19

definitive management

Answer 19

non surgical: air enema or water enema, successful in over 80% of cases, carried out under fluoroscopic guidance
surgical: where non-surgical reduction is unsuccessful, or there is evidence of perforation or peritonitis, surgically manually reduce the intussusception. may be performed laparoscopically
if unsuccesful: bowel resection may be requred

Question 20

complications of intussusception

Answer 20

main causes of mortality are late presentation, sepsis, and failure to instigate appropriate fluid resuscitation
serious complications are uncommon when identified and treated promptly
delay to definitive management may cause bowel necrosis, perforation, peritonitis and sepsis.