1. MEGACOLON
VIKAS.K.M
2002 MBBS

2. MEGACOLON
DEFINITION
Distention of the colon to greater than 6 or 7 cm in diameter

3. HIRSCHSPRUNG’S DISEASE

4. CONGENITAL HIRSCHSPRUNG’S DISEASE
Neurogenic form of intestinal obstruction in which there is an absence of ganglion cells in the myenteric & submucosal plexus
1 in 4500
Sex ratio 4:1
Harald Hirschsprung
( )

5. HIRSCHSPRUNG’S DISEASE
GENETICS
Hetrogeneous
Mutations
RET gene & RET ligands
Endothelin receptor system
3-5% have down’s syndrome

6. HIRSCHSPRUNG’S DISEASE
Hydrocephalus
VSD
Meckel’s diverticulum
Definite family history

7. PATHOLOGY
FAILURE OF MIGRATION of neuroblasts into the gut from vagal nerve trunks
ABSENCE of ganglion cells in neural plexus
HYPERTROPHY of nerve trunks

8. MACROSCOPICALLY The affected segment is NOT DISTENDED
Properly innervated upstream segment DILATES
Wall may be thinned
or thickened
Stercoral ulcers

9. HIRSCHSPRUNG’S DISEASE

10. HIRSCHSPRUNG’S DISEASE
Dilation of bowel proximal to the affected region

11. HIRSCHSPRUNG’S DISEASE

12. TOTAL COLONIC HIRSCHSPRUNG’S DISEASE
The transition zone (arrow) is in the small intestine

13. STERCORAL ULCERS

14. MICROSCOPICALLY
ABSENCE OF GANGLION CELLS

15. CLINICAL FEATURES Delayed passage of meconium(95%)
Abdominal distension
Bilious vomiting
Severe diarrhoea altrenating with constipation(10-15%)
Enterocolitis of hirchsprung’s disease

17. DIAGNOSIS

18. DIAGNOSIS ABDOMINAL RADIOGRAPH Dilated bowel loops with fluid levels
Intramural gas – enterocolitis
Free peritonial gas - perforation

19. ABDOMINAL RADIOGRAPH
Dilated bowel loops
Fluid levels

20. DIAGNOSIS BARIUM ENEMA Indicate length & site
No definitive cutoff point indicating transition zone
Evacuation of contrast may take
24 – 48 hours
Transition zone clear on delayed x-ray

21. BARIUM ENEMA Coning down of transition zone Irregularity in the mucosa
Abnormal contractions TZ

22. BARIUM ENEMA Contracted diseased segment (black arrow),
dilatation of normal bowel segment (red arrow)
and the transitional zone (TZ)

23. BARIUM ENEMA TZ

24. DIAGNOSIS RECTAL BIOPSY Submucosal suction biopsy is adequate in 90%
Full thickness operative biopsy in more emergent circumstances
Absence of ganglion cells in at least 10 sections – diagnosis confirmed
Increased Ach staining of neurofibrils

25. RECTAL BIOPSY

26. Ach STAINING
NORMAL
INSCREASED Ach STAINING

27. DIAGNOSIS ANORECTAL MANOMETRY Measures anorectal intraluminal pressure
Absent rectoanal inhibitory reflex indicating a lack of relaxation of the internal sphincter characteristic of aganglionosis

28. ANORECTAL
MANOMETRY

29. DIFFRENTIAL DIAGNOSIS
HYPOTHYROIDISM
MECONIUM PLUG SYNDROME
COLONIC NEURONAL DYSPLASIA
ADYNAMIC ILEUS WITH SEPSIS
INTESTINAL PSEUDO-OBSTRUCTION

30. TREATMENT

31. TREATMENT Depends on Age Length of involved segment
Severity of symptoms
Presence of enterocolitis

32. TREATMENT NEONATAL PERIOD TEMPORARY DECOMPRESSING COLOSTOMY
At least 10 cm proximal to transition zone

33. COLOSTOMY

34. TREATMENT 6 MONTH – ONE YEAR A definitive pull-through procedure using
SOAVE(endorectal)
DUHAMEL(retrorectal)
SWENSON(rectosigmoidectomy)

35. PULL-THROUGH PROCEDURE
Each is done a little differently, but all involve removing the part of the intestine that isn't working and connecting the healthy part that's left to the anus. After pull-through surgery, the child has a working intestine

36. SOAVE PROCEDURE

37. DUHAMEL PROCEDURE

38. SWENSON PROCEDURE

39. OPERATIVE FINDING OF TRANSITION ZONE

40. PROGNOSIS Overall survival in > 90% cases Rare deaths due to –
Delayed diagnosis
Complications
> 96% continent
Long term follow up is important

41. ACQUIRED MEGACOLON

42. ACQUIRED MEGACOLON CAUSES Chagas disease Organic obstruction of bowel
Toxic megacolon
Fuctional psychosomatic
disorder

43. ACQUIRED MEGACOLON Can occour at any age
Except for chagas disease,where inflammatory involvment of ganglia is evident,the remaining forms are not associated with deficiency of mural ganglia

44. CHAGAS DISEASE Protozoosis Flagellate protozoa Trypanosoma cruzi
Destruction of the autonomic nervous system innervation of the colon leads to a loss of the normal smooth muscle tone of the wall and subsequent gradual dilation
REDUVID BUG

45. MEGACOLON IN CHAGAS DISEASE

46. TOXIC MEGACOLON DEFINITION Total or segmental
Toxic megacolon is the clinical term for an acute toxic colitis with dilatation of the colon
Total or segmental
Hallmarks - nonobstructive colonic dilatation larger than 6 cm and signs of systemic toxicity

47. TOXIC MEGACOLON
TOXIC MEGACOLON

48. TOXIC MEGACOLON
Colon is dilated and shows hemorrhagic necrosis

49. TOXIC MEGACOLON CLASSIC ETIOLOGIES Ulcerative colitis Crohn colitis
Pseudomembranous colitis
Ulcerative colitis
Crohns disease
Pseudomembranous colitis

50. TOXIC MEGACOLON INFECTIOUS CAUSES Salmonella species Shigella species
Campylobacter species
Yersinia species
Clostridium difficile
Entamoeba histolytica
Cytomegalovirus
OTHER CAUSES
Radiation colitis
Ischemic colitis
Nonspecific colitis secondary to chemotherapy

51. PATHOPHYSIOLOGY
The microscopic hallmark - inflammation extending beyond the mucosa into the smooth-muscle layers and serosa
NO involved in the pathogenesis
NO inhibits smooth-muscle tone
NO generated by inflammatory cells

52. CLINICAL FEATURES Abdominal pain Severe diarrhoea Abdominal distention
Generalised tenderness
Fever,leucocytosis,tachycardia
pallor & lethargy

53. DIAGNOSTIC CRITERIA - Jalan et al
Radiographic evidence colonic dilatation
Three of the following - Fever (>101.5°F), tachycardia (>120), leukocytosis (>10.5), or anemia
One of the following - Dehydration, altered mental status, electrolyte abnormality, or hypotension

54. INVESTIGATIONS

55. LAB STUDIES Blood examination - leukocytosis with a left shift
bloody diarrhea results in anemia
Electrolyte disturbances
ESR & CRP usually are
elevated

56. IMAGING STUDIES ABDOMINAL RADIOGRAPH
Dilated (>6 cm) transverse colon
Loss of colonic haustrations
pseudopolyps
Free intraperitoneal air

57. ABDOMINAL RADIOGRAPH

58. IMAGING STUDIES CT – SCAN Perforation Abscess BARIUM ENEMA
Avoid barium studies
perforation

59. ENDOSCOPY Diagnosis is in doubt & patient is not toxic
Flexible sigmoidoscopy or colonoscopy
Perforation is an obvious potential complication with this approach

60. ENDOSCOPY The mucosa is grossly denuded, with active bleeding noted
Patient had her colon resected very shortly after this view was obtained

61. MEDICAL TREATMENT
MEDICAL MANAGEMENT

62. MEDICAL TREATMENT 3 main goals
Reduce colonic distension to prevent perforation
Correct fluid and electrolyte disturbances
Treat toxemia and precipitating factors

63. MEDICAL TREATMENT IV fluids Electrolyte resuscitation
Nasogastric suction
Broad spectrum antibiotics
Total parenteral nutrition
Intravenous steroids
No response in hrs - surgery

64. SURGICAL MANAGEMENT

65. SURGICAL MANAGEMENT INDICATIONS- For urgent intervention
Early surgical consultation is essential
INDICATIONS- For urgent intervention
Free perforation
Massive hemorrhage
Increasing toxicity
Progression of colonic dilatation

66. SURGICAL MANAGEMENT
Acute toxic megacolon – high operative morbidity & mortality
Conservative approach is appropriate
Anal sphincter sparing procedures-possibility of subsequent surgical correction for continence

67. SURGICAL MANAGEMENT WHEN URGENT COLECTOMY REQUIRED
TOTAL ABDOMINAL COLECTOMY
BROOKE ILEOSTOMY
HARTMANN’S POUCH

68. TOTAL ABDOMINAL COLECTOMY

69. BROOKE ILEOSTOMY
BROOKE ILEOSTOMY

70. HARTMANN’S POUCH This surgery leaves you with only one stoma and the
non-functional
end of the bowel
simply stitched or
stapled shut and
left inside you until
reconnection can take place.

71. SUMMARY HIRSCHSPRUNG’S DISEASE
Hirschsprung’s disease is a defined clinical entity with an unclear etiology
Early diagnosis,surgical expertise & multidiciplinary support
Current trends are towards any of the pull-through procedures

72. SUMMARY TOXIC MEGACOLON
Nonobstructive colonic dilatation larger than 6 cm and signs of systemic toxicity
Combined aggressive medical & surgical treatment
Total abdominal colectomy,Brooke ileostomy & Hartmann’s pouch

73. Thank you. . .