Constipation

Question 1

What social problems can cause constipation?

Answer 1

Diet e.g. low fluid, fibre or excess milk

Potty training difficulties

Question 2

What physical things could cause constipation? [4]

Answer 2

Meds e.g. Gaviscon or anti-spasmodics [1]
Intercurrent Illness [1] - pyrexial, dehydrated forming hard stool
Anatomical Abnormalities [1] eg anal stenosis, anterior anus, Hirschsprung’s disease, lead poisoning
Hypothyroidism [1]

Question 3

Most chronically constipated kids don’t have a physical cause, instead they get into a difficult cycle

Answer 3

First they get an episode of constipation
This leads to a large hard stool which causes pain or a fissure
The kid learns to withhold stool to avoid the pain which leads to further constipation etc etc

Question 4

Other than not passing stool, how would a chronically constipated kid present? [4]

Answer 4

• Poor appetite
• Irritable and lacking energy
• Abdo pain/distension, diarrhea
• Withholding or straining

Question 5

How would we go about managing a chronically constipated child with a megarectum? [4]

Answer 5

1. Empty impacted rectum
   • Start 4 sachets of movicol and increase from there but outflow constipation can occur, senna then osmotic laxative
2. Empty colon
3. Maintain regular stool passage
   - Encourage sit on toilet after meals to stimulate physiological gastro-colical reflex and use of star chart
4. Slow weaning off treatment – more dependence on non-rx mx

Question 6

What are the types of laxatives? [3]

Give 2 cons of laxatives

Answer 6

Osmotic e.g. Lactulose
Stimulant e.g. Senna
Isotonic e.g. Movicol (polyethylene glycol + electrolytes)
abdo pain, unpleasant taste; non-compliance – give at night

Question 7

What can we do if we suspect impaction? [2]

Answer 7

Colonic marker x-ray

Question 8

What other complication can occur from chronic constipation? [3]

Answer 8

UTI due to mass of stool causing urinary stasis
Soiling
Megarectum

Question 9

Hirschsprung disease
Ax [2]
RF
Pathophys

Answer 9

Ax: deletion of segment of long arm of chromosome 12 causes aganglionic bowel segment
RF: down syndrome
Px: developmental failure of parasympathetic Auerbach and Meissner plexuses

Question 10

Hirschsprung disease
Presentation in neonates [1], older children [4]
Ix [3]

Answer 10

• Neonatal: failure or delay in passing meconium <48h
• Older children: constipation, abdominal distension, explosive passage of liquid and foul stool (enterocolitis due to stool stasis and bacterial overgrowth)
Ix:
- AXR (air-fluid levels, dilated colon)
- barium enema (contracted distal bowel and dilated proximal bowel with demonstration of transition zone in between)
- full thickness rectal biopsy (diagnostic = absence of ganglion cells and presence of thickened non-myelinated nerves)

Question 11

Hirschsprung disease
Management if:
1. Typical (rectosigmoid) or long segment [3]
2. Total aganglionosis [2]
3. Short segment [1]
4. Enterocolitis [3]

Answer 11

• Typical (rectosigmoid) or long segment: bowel irrigation (NOT enema) and definitive surgical correction (pull through of ganglionic bowel) performed in 1st week of life
• Total aganglionosis: ileostomy then definitive surgical correction
• Short segment: laxatives
o Enterocolitis:
- Bowel irrigation
- add in IV fluids and abx
+/- ileostomy or colostomy if irrigation in effective