Case 1 (mild CDAD ): A 48-year-old female received antibiotics (oral clindamycin) after undergoing endodontic surgery. 8 days after the antibiotic course, she had diarrhea, she took metronidazole, and her C. difficile infection resolved.
Case 2 (severe CDAD): A 31-year-old pregnant woman developed severe CDAD after receiving antibiotics for a urinary infection. She underwent surgery to remove part of her colon, but her condition worsened, and she died.
Clostridium difficile: is a gram-positive, spore forming, toxin-producing, anaerobic bacillus that causes diseases of the GIT ranging from asymptomatic colonization to a life threatening condition known as “toxic megacolon.”
It is spread by the fecal-oral route and can be ingested in a vegetative or spore form.
The primary virulence factors are:
the large clostridial cytotoxins toxins A and B that cause inflammation and mucosal damage and lead to diarrhea or colitis. In people who develop CDAD after taking antimicrobial agents, their S&S typically start within 3-weeks of initiating antimicrobial therapy, but they can begin as early as the 1st day of treatment or as late as 2-months after its completion
Mild-moderte CDAD: non-bloody diarrhea with few systemic symptoms.
Moderate CDAD: fever, abdominal pain and leukocytosis. (TX should be initiated at this stage)
Severe CDAD: hemodynamic instability and other signs of a sepsis-like syndrome. The most serious complications
include paralytic ileus, peritonitis and toxic megacolon; in many cases, these complications require surgical removal of the colon.\
Taking cephalosporins, penicillins or clindamycin. being older than 65 years, undergoing nasogastric intubation, having severe comorbidities and experiencing long hospital stays
Treatment: discontinue the use of any inciting antimicrobial agents or narrow the spectrum of AB
Prescribe to patients with CDAD a 10-day course of oral antimicrobial agent to treat C. difficile. For mild-to-moderate CDAD, oral metronidazole usually is effective. For severe CDAD, oral vancomycin may be a better choice.
Interaction: Metronidazole may slow the elimination of lithium from the body which will increase blood levels of lithium and cause toxic effects.
- Tetracyclines or other broad-spectrum antibiotics with oral anticoagulants
Interaction: it has been hypothesized that broad-spectrum antibiotics such as tetracyclines, amoxicillin and ampicillin can reduce endogenous vitamin K levels and enhance the effects of oral anticoagulants by decimating the normal gut flora that produce vitamin
- Antibiotics with oral contraceptives
Interaction: may lead to subtherapeutic blood levels of combined oral contraceptive and leading to contraception failure. Additional method of contraception is adviced.
With Rifampin antibiotic alternative method is recommended.