Hirschsprungs disease

Question 1

define Hirschprungs disease

Answer 1

congenital condition

-nerves of the myenteric plexus are absent in the distal bowel and rectum

Question 2

what nerve plexueus are affect by Hirschprungs disease (2) and what do they form
-are they sympathetic or parasympathetic

Answer 2

Auerbach and Meissner plexuses
-forms the enteric nervous system (the brain of the gut)

-parasympathetic

Question 3

function of the myenteric plexues

Answer 3

stimulating peristalsis of the large bowel

-without this stimulation-> bowel looses its motility and stops being able to pass food along its length

Question 4

key pathophys of Hirschprungs disease

Answer 4

absence of parasympathetic ganglion cells
-during fetal development these ganglion cells start higher in the GI tract and gradulally migrate down to the distal colon and rectum

-in Hirschprungs disease these parasympathetic ganglion cells do not travel all the way down the colon
-section of clon at the end is left without these cells

Question 5

how can Hirschprungs disease vary between patients
-whats it called when it afffects the whole colon

Answer 5

length of colon without innervation varies between patients from small amount to entire colon

-if the full colon is affected-> total colonic aganglionosis

Question 6

what happens with the agangionic sectrion of the colon in Hirschprungs disease

Answer 6

it does not relax-> causing it to become constricted

-causes loss of movement of feaces and obstruction of the bowel

-proximal to the obstruction the bowel becomes distened and full

Question 7

risk factor of Hirschprungs disease 1

Answer 7

fmily history greatly increases risk

Question 8

associated syndromes to Hirschprungs disease 4

Answer 8

downs syndrome

neurofibromatosis

Waardenburg syndrome (genetic condition- pale blue eyes, hearing loss, patches of white skin and hair )

multiple endocrine neoplasia type 2

Question 9

presentation of Hirschprungs disease 6

Answer 9

severity of presenation and age at diagnosis depends on extent of bowel affected

severe case- acute intestinal obstruction after birth or:
-delay in passing meconium (more than 24hrs)
-chronic constiaption since birth
-abdo pain and disitenion
-vomitting
-poor weight gain and failure to thrive

Question 10

define Hirschsrpung assocaited enterocolitis

Answer 10

inflammation and obstruction of the intesisne
-occurs in 20% of neonates with Hirschprungs disease

Question 11

presentation of Hirschsrpung assocaited enterocolitis 4

Answer 11

presents within 2-4 weeks of birth with
-fever
-abdo distention
-diarrhoea (often bloody)
-features of sepsis

Question 12

what can Hirschsrpung assocaited enterocolitis lead to 2

Answer 12

life threatening toxic megacolon
and
perforation

Question 13

management of Hirschsrpung assocaited enterocolitis 3

Answer 13

urgent ABx

fluid resus

decompression

Question 14

investigations of Hirschprungs disease 2

Answer 14

abdo xray

rectal biopsy

Question 15

management of Hirschsprungs disease 3

Answer 15

fluid resus

managemnet intesitnal obstruction

surgical removal of aganglionic section of bowel
-can be left with dome degree of incontinence