Pathogenic Clostridia, including Botulism and Tetanus (page 2)
(This chapter has 4 pages)
© Kenneth Todar, PhD
Clostridium difficile causes antibiotic-associated
(AAD) and more serious intestinal conditions such as colitis and
colitis in humans. These conditions generally result from
of Clostridium difficile in the colon, usually after the normal
flora has been disturbed by antimicrobial chemotherapy.
People in good health usually do not get C. difficile disease.
Individuals who have other conditions that require prolonged use of
and the elderly are at greatest risk. Also, individuals
have recently undergone gastrointestinal surgery, or have a serious
illness, or who are immunocompromised, are at risk.
C. difficile produces two toxins: Toxin A is referred to as
enterotoxin because it causes fluid accumulation in the bowel. Toxin B
is an extremely lethal (cytopathic) toxin.
Stool cultures for diagnosis of the bacterium may be complicated by
the occurrence and finding of non toxigenic strains of the
so the most reliable tests involve testing for the presence of the
A and/or Toxin B in the stool. The toxins are very unstable. They
at room temperature and may be undetectable within two hours after
of a stool specimen leading to false negative results of the diagnosis.
In the hospital and nursing home setting, C. difficile
can be minimized by judicious use of antibiotics, use of contact
with patients with known or suspected cases of disease, and by
of an effective environmental and disinfection strategy.
Clostridium difficile infections can usually be treated
with a 10-day course of antibiotics including metronidiazole or
on blood agar
C. difficile endospores.