Microbiology – MCQ 31 – Bacteroides fragilis

With reference to Bacteroides fragilis the following statements are true, except:
a) B. fragilis is the same frequent anaerobe isolated from clinical samples.
b) B. fragilis is not uniformly sensitive to metronidazole
c) The lipopolysaccharide formed by B. fragilis is structurally and functionally different from the conventional endotoxin
d) Shock and disseminated intravascular coagulation are common in Bacreriodes bacteremia

Correct answer : d) Shock and disseminated intravascular coagulation are common in Bacreriodes bacteremia

Bacteroides:

  • Gram negative anaerobic bacilli
  • Most common anaerobic pathogen isolated from clinical specimens
  • Virulence factors include capsular polysaccharides and lipopolysaccharide endotoxin
  • Lipopolysaccharide endotoxin is much less toxic compared to other gram negative bacteria
  • Hence infections do not directly produce signs of sepsis, which is common in other gram negative bacteria
  • Some are resistant to metronidazole