Week 11 - Topic 4: C difficile Flashcards
What is C difficile (CD)?
Spore-forming gram + anaerobic bacillus
When is CD a spore vs in its vegetative state?
Spore: in the environment
Vegetative: in the GI tract
What causes disease from CD?
The toxin secreted by CD
What % of CD organisms produce toxins?
80%
5-20% don’t produce toxin and thus don’t cause colitis
What are the two toxins produced by CD?
Toxin A enterotoxin: fluid secretion, mucosal damage and intestinal inflammation
Toxin B cytotoxin: cellular damage
Lead to colon damage
How is CD stool set apart from other poops?
It has a notable odour
You have been colonized with CD and have symptoms. What illness do you have?
Clostridium difficile infection (CDI)
True or False: If you have CD in the gut, you will most likely develop symptoms.
True, only 1-15% are asymptomatic
What colonized age group is usually asymptomatic and why?
Newborns (30-80%) bc they lack the receptors for toxins
Why do CD spores germinate?
They germinate (usually in the large intestine) because of the imbalance of normal fecal flora
What causes imbalances to normal fecal flora?
1) Abx **
2) Surgery (stomach/bowels) –> exposure to Abx and spores
3) Old age –> exposure to hospitals, LTC
4) Chemo, laxatives –> change in bowel flora
What are the 5 manifestations of the CDI spectrum (going from mild to bad)?
1) Asymptomatic carrier (subclinical)
2) Mild self-limited diarrhea
3) Colitis w/o pseudomembranes
4) Pseudomembranous colitis
5) Fulminant colitis, toxic megacolon, intestine rupture (high mortality)
When do people with CDI produce symptoms?
80% within 4-9 days of antimicrobial therapy
20% within 8-10 weeks after cessation of therapy
(Monitor sx during and after abx therapy)
What are common symptoms of CDI?
Mucoid, green, foul-smelling diarrhea***
Abdominal cramps
What are the 5 characteristics of pseudomembranous colitis?
1) Rapid elevation of peripheral WBC
2) Hypoalbuminemia of 3.0 g/dL
3) Hemodynamic instability
4) Blood diarrhea
5) Development of multi-organ dysfunction
Is pseudomembranous colitis dangerous?
Yes, death rate of 40-80%
If you were to observe a colon with pseudomembranous colitis what would you see?
Slime, blisters, ulcers, necrosis
Why do pts with fulminant CD have little diarrhea?
Their large intestine is so enlarged/distended that it won’t let out diarrhea = toxic megacolon
What are the 4 characteristics of culminant CD?
1) Preceded by hemodynamic instability
2) Multi-organ dysfunction
3) Toxic megacolon
4) Colonic perforation
When imaging toxic colitis for diagnosis, what do you see?
Damage to the intestinal wall:
- No contraction of ileus
- Loss of muscle tone = abdo distention
- Gas buildup in intestines = “thumbprint”
What are the sx of fulminant CD?
- Severe lower quadrant or diffuse abdo pain
- Distention
- Bloody diarrhea
- High fever, chills, leukocytosis
How do you diagnose CD?
1) Culture of bacteria (rare)
2) Toxin detection by PCR (24-48h)
3) Endoscopic visualization of gut (if pt has sx but tests come back negative)
How do you collect specimen for CD diagnosis?
Place freshly passed (1-2h ago) watery, unformed stool (10-20 mL) in clean container
How do you collect specimen for CD diagnosis for those who wear diapers?
Place a bag in diaper to collect it while you make sure the person doesn’t develop a rash or urinate in it