C. diff Colitis

1
C. diff Colitis

• A gram () spore forming anaerobic bacillus
• First associated with antibiotic induced diarrhea
  in the late 1970s
• Now accounts for 25 of all cases of
  antibiotic-associated diarrhea currently most
  common cause of nosocomial diarrhea
• ANY antibiotic can cause this clinda,
  ampicillin, amoxicillin, and cephalosporins
• Antineoplastic agents and immunosuppressive drugs
  also implicated

2
C. diff Colitis

• Infants and young children commonly harbor C diff
  and then the of carriers declines with age
• During hospitalization, colonization frequently
  occurs (up to 21) via fecal-oral route
• Clinical symptoms develop in about 1/3 of
  colonized patients
• Transmission patient to patient, hospital
  personnel, contaminated surfaces

3
Pathogenesis

• Disruption of normal flora of the colon
• Two factors affecting severity comorbid
  conditions and /- of anti-ToxinA antibody
• Clinically significant strains produce toxin A
  and toxin B
• Toxin A binds to gut epithelial cells, modifies a
  GTP binding protein, which leads to
  disaggregation of actin disruption of tight
  junctions cell death
• Toxin B less well characterized

4
Clinical manifestations

• Diarrhea, abdominal cramping, occult GI bleeding,
  colitis with pseudomembranes, colitis without
  pseudomembranes, fulminant colitis
• Fever, nausea, anorexia, malaise
• Associated with toxic megacolon, chronic diarrhea
  with hypoalbuminemia, reactive arthritis
• Some individuals with toxigenic strains remain
  asymptomatic

5
Diagnosis

• Leukocytosis usually present
• Imaging AXR ileus, mucosal thickening
  (thumbprinting) Abd CT thickened wall of colon
• C diff culture takes 2-3 days to complete, does
  not distinguish toxigenic from nontoxigenic
  strains
• Most sensitive and specific test is the tissue
  culture assay for toxin B from stool

6
Diagnosis

• Most tests used are ELISA based assays for toxin
  A and/or B
• Sensitivity 71 and specificity of 94
• Endoscopy usually presence of nonspecific
  colitis, pseudomembranes in severe cases (yellow
  adherent plaques)
• Endoscopy is reserved for special situations
  (ruling out alternative diagnosis)

7
Treatment

• Discontinue inciting antibiotics
• Supportive therapy IVF, antiemetics
• Avoid antiperistaltic and opiate drugs
• Antimicrobial therapy for moderate or severe
  disease oral metronidazole, oral vancomycin for
  14 days
• Critically ill, unable to take po iv
  metronidazole, vancomycin enema