Section: Colorectal
Definition
- Uncommon, of unknown aetiology.
- Other conditions with gut dilatation – Hirschsprung’s disease, chronic intestinal pseudo-obstruction, not included since aetiology is known.
Aetiology
Unknown
Clinical
- Usually present with intractable constipation in the first 2 decades of life.
- Idiopathic megarectum: often have faecal incontinence in context of recurrent faecal impaction requiring surgical disimpaction.
- Idiopathic megacolon: abdominal pain, distension
Management
- Disimpaction followed by osmotic Laxatives – needs titration so patient obtains semi-formed stool, 3x/day.
- Occasionally need rectal evacuation techniques e.g. suppository or biofeedback therapy.
- If medical therapy fails, needs surgery
- Overall surgery has variable success.
- Anorectal physiology, whole-gut transit studies and defaecating proctography do not help identify patients who may benefit. Anorectal physiology can identify presence of recto-anal inhibitory reflex, excludes differential of Hirschsprung’s disease.
- Total colectomy with ileorectal anastomosis – greatest level of patient satisfaction
- Other options include Duhamel procedure, anal myomectomy and restorative proctocolectomy.
- If initial surgery has failed or as primary procedure, stoma has good results.