Pathogenic Microbiology Exam 2 with verified detailed ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
solutions
Clostridium difficile: biology - correct answer✔✔large, anaerobic, gram-positive, spore ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
forming rods ||\\//||
Clostridium difficile: virulence - correct answer✔✔*Toxin A (enterotoxin): attracts neutrophils ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
and stimulates cytokine release
||\\//|| ||\\//|| ||\\//|| ||\\//||
*Toxin B (cytotoxin): breaks down cell structure (actin) and increases GI permeability
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
*Surface layer proteins: attach to intestinal epithelium ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium difficile: epidemiology - correct answer✔✔can inhabit intestines commensally, ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
but become overgrown in cases of antibiotic use due to their wide range of drug resistance
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium difficile: disease - correct answer✔✔- antibiotic-associated diarrhea: usually self ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
limiting
- pseudomembranous colitis: profuse diarrhea, cramping, FEVER, plaque formation over
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
colonies (can be fatal) ||\\//|| ||\\//|| ||\\//||
Clostridium difficile: diagnosis - correct answer✔✔detection of enterotoxin (A) or cytotoxin ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
(B) in feces ||\\//|| ||\\//||
Clostridium difficile: treatment - correct answer✔✔discontinue causative antibiotic, severe ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
disease requires metronidazole or vancomycin therapy ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
*relapse is common due to spore survival* ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium perfringens: biology - correct answer✔✔large, non-motile, anaerobic, gram- ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
positive, spore forming rods ||\\//|| ||\\//|| ||\\//||
,Clostridium perfringens: virulence - correct answer✔✔*Alpha toxin: cause massive hemolysis,
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
increased permeability, tissue destruction, hepatic toxicity, and myocardial dysfunction
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
*Heat-labile enterotoxin: a superantigen produced by type A strains that induces cellular fluid ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
and ion loss
||\\//|| ||\\//|| ||\\//||
Clostridium perfringens: epidemiology - correct answer✔✔ubiquitous in soil, dust, water and
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
mammalian intestinal tracts ||\\//|| ||\\//||
*type A strains are largely responsible for human infection*
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium perfringens: disease - correct answer✔✔- fasciitis: pus in muscle planes ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
- myonecrosis: pain, edema, cellulitis, gas accumulation in tissues (high mortality)
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
- clostridial food poisoning (intoxication): short incubation period before onset of abdominal
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
cramping and watery diarrhea that last approx. 24hrs (NO systemic symptoms)
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium perfringens: diagnosis - correct answer✔✔presence of gram-positive rods and no
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
leukocytes in tissues
||\\//|| ||\\//|| ||\\//||
Clostridium perfringens: treatment - correct answer✔✔- symptomatic treatment of food ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
poisoning
- severe soft tissue infections require surgical debridement and high dose penicillin therapy
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium tetani: biology - correct answer✔✔large, motile, OXYGEN SENSITIVE, gram- ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
positive, spore forming rods ||\\//|| ||\\//|| ||\\//||
Clostridium tetani: virulence - correct answer✔✔*tetanolysin: oxygen labile hemolysis ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
**tetanospasmin: plasmid encoded, heat-labile neurotoxin (A-B toxin) that blocks release of ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
inhibitory neurotransmitters glycine & GABA ||\\//|| ||\\//|| ||\\//|| ||\\//||
, Clostridium tetani: epidimiology - correct answer✔✔ubiquitous in most soils and can colonize
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
mammalian gastrointestinal tracts
||\\//|| ||\\//|| ||\\//||
Clostridium tetani: disease - correct answer✔✔tetanus or "lockjaw": unrelenting muscle ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
spasms (high mortality) ||\\//|| ||\\//||
Clostridium tetani: diagnosis - correct answer✔✔clinical signs are diagnostic - microscopy ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
and culture are insensitive
||\\//|| ||\\//|| ||\\//||
Clostridium tetani: treatment - correct answer✔✔wound debridement and metronidazole ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
therapy, human tetanus immunoglobulin, & tetanus toxoid vaccination ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
||\\//|| *penicillin is effective BUT also blocks GABA* ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium botulinum: biology - correct answer✔✔large, anaerobic, fastidious, gram-positive,
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
spore forming rods
||\\//|| ||\\//|| ||\\//||
Clostridium botulinum: virulence - correct answer✔✔botulinum toxin: blocks release of ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
acetylcholine (neurotransmitter) resulting in flaccid paralysis; protective proteins allow ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
unhindered passage through GI tract ||\\//|| ||\\//|| ||\\//|| ||\\//||
*the most toxic substance known to man
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium botulinum: epidemiology - correct answer✔✔found naturally in soil/dust, but can||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
also thrive in poorly canned alkaline vegetables
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium botulinum: disease - correct answer✔✔- foodborne botulism (intoxication): ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
blurred vision, dry mouth, constipation, abdominal pain, and flaccid paralysis (death due to
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
respiratory paralysis) ||\\//||
- infant botulism (toxi-infection): constipation, weak cry, failure to thrive in infants <1yr (from
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
honey containing spores)
||\\//|| ||\\//|| ||\\//||
solutions
Clostridium difficile: biology - correct answer✔✔large, anaerobic, gram-positive, spore ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
forming rods ||\\//||
Clostridium difficile: virulence - correct answer✔✔*Toxin A (enterotoxin): attracts neutrophils ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
and stimulates cytokine release
||\\//|| ||\\//|| ||\\//|| ||\\//||
*Toxin B (cytotoxin): breaks down cell structure (actin) and increases GI permeability
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
*Surface layer proteins: attach to intestinal epithelium ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium difficile: epidemiology - correct answer✔✔can inhabit intestines commensally, ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
but become overgrown in cases of antibiotic use due to their wide range of drug resistance
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium difficile: disease - correct answer✔✔- antibiotic-associated diarrhea: usually self ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
limiting
- pseudomembranous colitis: profuse diarrhea, cramping, FEVER, plaque formation over
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
colonies (can be fatal) ||\\//|| ||\\//|| ||\\//||
Clostridium difficile: diagnosis - correct answer✔✔detection of enterotoxin (A) or cytotoxin ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
(B) in feces ||\\//|| ||\\//||
Clostridium difficile: treatment - correct answer✔✔discontinue causative antibiotic, severe ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
disease requires metronidazole or vancomycin therapy ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
*relapse is common due to spore survival* ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium perfringens: biology - correct answer✔✔large, non-motile, anaerobic, gram- ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
positive, spore forming rods ||\\//|| ||\\//|| ||\\//||
,Clostridium perfringens: virulence - correct answer✔✔*Alpha toxin: cause massive hemolysis,
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
increased permeability, tissue destruction, hepatic toxicity, and myocardial dysfunction
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
*Heat-labile enterotoxin: a superantigen produced by type A strains that induces cellular fluid ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
and ion loss
||\\//|| ||\\//|| ||\\//||
Clostridium perfringens: epidemiology - correct answer✔✔ubiquitous in soil, dust, water and
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
mammalian intestinal tracts ||\\//|| ||\\//||
*type A strains are largely responsible for human infection*
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium perfringens: disease - correct answer✔✔- fasciitis: pus in muscle planes ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
- myonecrosis: pain, edema, cellulitis, gas accumulation in tissues (high mortality)
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
- clostridial food poisoning (intoxication): short incubation period before onset of abdominal
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
cramping and watery diarrhea that last approx. 24hrs (NO systemic symptoms)
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium perfringens: diagnosis - correct answer✔✔presence of gram-positive rods and no
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
leukocytes in tissues
||\\//|| ||\\//|| ||\\//||
Clostridium perfringens: treatment - correct answer✔✔- symptomatic treatment of food ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
poisoning
- severe soft tissue infections require surgical debridement and high dose penicillin therapy
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium tetani: biology - correct answer✔✔large, motile, OXYGEN SENSITIVE, gram- ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
positive, spore forming rods ||\\//|| ||\\//|| ||\\//||
Clostridium tetani: virulence - correct answer✔✔*tetanolysin: oxygen labile hemolysis ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
**tetanospasmin: plasmid encoded, heat-labile neurotoxin (A-B toxin) that blocks release of ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
inhibitory neurotransmitters glycine & GABA ||\\//|| ||\\//|| ||\\//|| ||\\//||
, Clostridium tetani: epidimiology - correct answer✔✔ubiquitous in most soils and can colonize
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
mammalian gastrointestinal tracts
||\\//|| ||\\//|| ||\\//||
Clostridium tetani: disease - correct answer✔✔tetanus or "lockjaw": unrelenting muscle ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
spasms (high mortality) ||\\//|| ||\\//||
Clostridium tetani: diagnosis - correct answer✔✔clinical signs are diagnostic - microscopy ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
and culture are insensitive
||\\//|| ||\\//|| ||\\//||
Clostridium tetani: treatment - correct answer✔✔wound debridement and metronidazole ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
therapy, human tetanus immunoglobulin, & tetanus toxoid vaccination ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
||\\//|| *penicillin is effective BUT also blocks GABA* ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium botulinum: biology - correct answer✔✔large, anaerobic, fastidious, gram-positive,
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
spore forming rods
||\\//|| ||\\//|| ||\\//||
Clostridium botulinum: virulence - correct answer✔✔botulinum toxin: blocks release of ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
acetylcholine (neurotransmitter) resulting in flaccid paralysis; protective proteins allow ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
unhindered passage through GI tract ||\\//|| ||\\//|| ||\\//|| ||\\//||
*the most toxic substance known to man
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium botulinum: epidemiology - correct answer✔✔found naturally in soil/dust, but can||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
also thrive in poorly canned alkaline vegetables
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
Clostridium botulinum: disease - correct answer✔✔- foodborne botulism (intoxication): ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
blurred vision, dry mouth, constipation, abdominal pain, and flaccid paralysis (death due to
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
respiratory paralysis) ||\\//||
- infant botulism (toxi-infection): constipation, weak cry, failure to thrive in infants <1yr (from
||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//|| ||\\//||
honey containing spores)
||\\//|| ||\\//|| ||\\//||
