Pseudomembranous Colitis (PMC)

Document Sample
Pseudomembranous Colitis (PMC) Powered By Docstoc
					Benign Colorectal Conditions



         Dr. Simon Ng
        Surgery Team 3
         10 April 2003
                Topics
• Diverticular Disease

• Pseudomembranous Colitis

• (Inflammatory Bowel Disease)

• Colorectal Polyps

• Abdominal Stomas
Diverticular Disease
Diverticular Disease – Introduction 1
 • Outpouchings of colonic wall

 • Herniation of mucosa through points of
   weakness in the muscular wall – points of
   entry of the vasa recta

 • Most common in the sigmoid colon

 • False diverticulum

 • Pulsion diverticulum
Diverticular Disease – Introduction 2
 • Diverticulosis – presence of diverticula
   without inflammation
 • Diverticulitis – presence of inflamed
   diverticula
   • Uncomplicated diverticulitis – peridiverticulitis or
     phlegmon
   • Complicated diverticulitis – obstruction, free
     perforation, fistula, abscess
            Diverticulitis –
        Hinchey Classification
• Stage I – small confined pericolonic abscess

• Stage II – distant abscess
  (retroperitoneal/pelvic)

• Stage III – generalized suppurative peritonitis
  (abscess ruptured)

• Stage IV – faecal peritonitis (free rupture of a
  diverticulum)
Diverticular Disease - Epidemiology
 • Increased prevalence in western countries
 • Increased prevalence with age
   • 10% population at 40 years
   • 60% population at 80 years

 • Similar incidence in men and women
 • More common in developed countries
  (?related to diet)
Diverticular Disease - Pathogenesis
 • 2 factors: increased intraluminal pressure and
   weakness of the colonic wall
 • Lack of fibres in western diet results in low stool
   bulk
 • Induces increased segmentation of colonic
   musculature
 • Increased intraluminal pressure results in herniation
 • Aging associated with decreased tensile strength of
   the colonic musculature
Diverticulosis – Clinical Features
• Asymptomatic

• Mild abdominal cramping, bloating,
  flatulence, irregular bowel habit

• ‘Painful diverticular disease’ – chronic
  colicky abdominal pain

• Massive GIB
 Diverticulitis – Clinical Features
• LLQ pain (93-100%)
• Fever (57-100%)
• Leukocytosis (69-83%)
• Generalized peritonitis
• Fistula to bladder, vagina, skin
• Colonic stricture (after repeated attacks)
• Small bowel obstruction (adherence of small bowel
  to an inflammatory mass)
Diverticulitis – Natural History
• 10-20% of patients with diverticulosis will develop
  diverticulitis

• Majority have a single attack (10-45% have recurrent
  attacks)

• 70% chance of response to medical treatment after
  first attack

• Only 10% chance of response to medical treatment
  after 3rd attack
   Diverticular Disease - Diagnosis
• Diverticulosis
  • Barium enema or colonoscopy

• Diverticulitis
  • Clinical assessment (It has been recommended that
    when the clinical picture is clear additional tests are not
    necessary to make a diagnosis)
  • CT scan
  • Full colonic investigation after the inflammatory episode
    has settled – to r/o cancer
    Diverticulitis – Treatment
• Medical therapy (successful in 70-80% of
  patients)

• Percutaneous therapy – for drainage of
  pericolonic abscess

• Surgical therapy – emergent or elective
  operation
            Medical Therapy
• In the absence of systemic symptoms and signs,
  patients may be treated on an outpatient basis with
  low residue diet and oral antibiotics

• Hospitalization is required for increasing abdominal
  pain, fever, or inability to tolerate oral intake

• Need bowel rest, observation and IV antibiotics

• 70-80% of patients respond to medical therapy –
  improvement should be apparent within 48 hours
Surgical Therapy – Indications 1

• Emergent
  • Failed medical treatment

  • Abscess could not be drained by
   percutaneous methods

  • Generalized peritonitis
  Surgical Therapy – Indications 2
• Elective
  • Patients who have had one episode of complicated
    diverticulitis (abscess, obstruction, fistula)
  • Patients who have had two episodes of acute
    diverticulitis severe enough to require hospitalization
  • Young and immunocompromised patients after one
    attack of acute diverticulitis
 Surgical Therapy - Principles
• Control of sepsis
• Resection of diseased tissue
• Restoration of intestinal continuity
• With or without a protective stoma
   Surgical Therapy – Options
• Outdated 3-stage colostomy and drainage
• Hartmann’s procedure
• Primary resection, anastomosis and diversion
• Primary resection and anastomosis (on-table
 lavage)
• Laparoscopic approach is feasible in Hinchey I
 and II cases
      Caecal Diverticulitis 1
• Common in the Oriental countries

• Usually solitary

• Pathogenesis may be different from the left
  sided disease

• ?Congenital

• ?True diverticulum
       Caecal Diverticulitis 2
• Clinically mimic acute appendicitis

• Diagnosis usually not established pre-op.

• Need to differentiate from CA intra-op.

• Exact surgical treatment remains
  controversial – leave it alone, diverticulectomy,
  or right hemicolectomy?

• Natural history less well understood
Pseudomembranous Colitis
        (PMC)
          PMC - Introduction
• Caused by Clostridium difficile infection

• A gram-positive anaerobic bacillus

• First identified in 1935 by Hall and O’Toole –
  ‘difficult’ to culture

• C. difficile spores are commonly found in the
  hospital environment
      PMC – Pathogenesis 1
• Normal stool contains >500 different bacteria
  at a concentration of 1012 per gram

• Antibiotic therapy can alter the faecal flora

• Broad-spectrum antibiotics with activity
  against enteric bacteria are the main culprits

• Clindamycin, penicillin, and cephalosporins
  are examples
      PMC – Pathogenesis 2
• Allows colonization of C. difficile transmitted
  by the faecal-oral route

• Pathogenic strains of C. difficile produce two
  exotoxins (toxin A & B)

• Act via cell membrane receptors and
  produce mucosal inflammation and cell
  damage
           PMC - Histology
• Diffuse epithelial necrosis and ulceration
• Overlaid by a pseudomembrane consisting
  of mucin, fibrin, leukocytes, and cellular
  debris
        PMC - Epidemiology
• In both infants and adults, infection is
  generally acquired in the hospital
• 50% of neonates are transient healthy
  carriers of C.difficile
• Only 1% of adults are asymptomatic carriers
• 10% patients on antibiotics develop
  diarrhoea
• Only 1% develop PMC
     PMC – Clinical Features
• History of antibiotic therapy within 6 weeks
• Even a single dose of antibiotic therapy can
  induce the disease
• Disease spectrum:
  • Mild diarrhoea
  • Colitis without pseudomembrane formation
  • Pseudomembranous colitis
  • Fulminant colitis
           PMC – Diagnosis
• Proctoscopy/Sigmoidoscopy
  • 2 to 10 mm yellow plaques with normal
    intervening mucosa
  • Rectum and sigmoid colon are typically involved
  • In 10% of cases, colitis is confined to the more
    proximal colon – may be missed by
    sigmoidoscopy

• Detection of toxin in stool by ELISA
         PMC – Treatment 1
• Discontinue antibiotic therapy

• Start oral antibiotic treatment:
  • Metronidazole – first line

  • Vancomycin – second line

• Symptoms usually improve within 72 hours

• May take 10 days for diarrhoea to stop
         PMC – Treatment 2
• If cannot tolerate oral antibiotics, can
  consider intravenous metronidazole
  (excretion of the drug into bile and exudation
  from the inflamed colon result in bactericidal
  level in faeces)
• Intravenous vancomycin should not be used
  because marked excretion of this drug into
  the gut lumen has not been demonstrated
         PMC – Treatment 3
• Mild diarrhoea and colitis usually respond to
  oral antibiotic treatment

• PMC requires aggressive resuscitation and
  treatment

• If fulminant colitis with toxic megacolon or
  perforation, surgery is required
Inflammatory Bowel Disease
Please refer to ……
Colorectal Polyps
          Colorectal Polyps
• Discrete elevation above the surface of
  epithelium
• Classification:
  • Hyperplastic
  • Hamartomatous
  • Inflammatory
  • Neoplastic

• Diagnosis and treatment by colonoscopy
Downloaded from Department of Surgery Intranet
  Surgery Grand Round on 29 December 2001
Polyps – Management 1

Initial management depends on:

  • Location: colon or rectum

  • Pedunculated or sessile
     Polyps – Management 2
• If pedunculated (colon or rectum)
   • Colonoscopic polypectomy
• If sessile
   • Polypectomy if feasible
   • If not
       • Colon: colectomy
       • Rectum: staged with EUS or MRI
         • T1 lesion or LN -: local excision or TEMS (need
           further radical surgery if subsequent pathology
           unfavourable)
         • T2 lesion or LN +: radical excision
      Polyps – Management 3
• For all polypectomy specimen, need to evaluate
  pathology for:
   • Histology
   • Margin
   • Stalk invasion
   • Lymphovascular invasion

• All these correlate with risks of recurrence and LN 2o,
  and will determine whether further definitive
  treatment is necessary
Abdominal Stomas
      Stomas - Introduction
• Stoma (Greek) = mouth or opening

• A surgically created communication between
  a hollow viscus and the skin

• Temporary or permanent

• Ileostomy or colostomy

• End or loop or double-barrelled
      Stomas - Examination
• In any discussions regarding stomas the
 following factors may need to be considered:
  • Form

  • Siting

  • Appliances

  • Complications
    Ileostomy or Colostomy
• Form?

• Mucosa?

• Content?

• Location?
       Permanent Stomas
• End stomas

• When there is no distal bowel – for
  permanent diversion
  • End colostomy for APR

  • End ileostomy for Proctocolectomy
         Temporary Stomas
• Loop stomas:
  • To protect a distal anastomosis
  • To prevent distal disease getting worse
    (defunction)
  • To decompress a distal obstructive lesion

• End stomas:
  • End colostomy in Hartmann’s procedure
Loop Ileostomy
Marked the proximal and distal limbs
Anchor to fascia
Bowel opened on distal limb
Proximal limb eversion
                Stomas - Siting
• Away from umbilicus, scars,
  costal margin and ASIS
• Lateral edge of the rectus
  sheath
• Ensure compatible with the
  clothing worn by the patient
• Ideally should be marked
  preoperatively with the
  patient in different positions
  by the stoma nurse
      Stomas - Complications
• Structural complications
   • Ischaemia/necrosis
   • Retraction
   • Prolapse
   • Parastomal herniation
   • Fistula formation

• Functional complications
   • Increased or decreased in output

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:80
posted:11/9/2012
language:Unknown
pages:64