Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/34

Click to flip

34 Cards in this Set

  • Front
  • Back
What do all of these organisms cause?

What do all of these organisms cause?

Inflammatory diarrhea

What do all of these organisms cause?

What do all of these organisms cause?

Non-inflammatory diarrhea

What type of organisms are these?

What type of organisms are these?

Anaerobes

What is the definition of acute diarrhea?


Chronic diarrhea?


Acute = 3 or more loose stools per day lasting less than 2 weeks



Chronic = persists for greater than four weeks

What is inflammatory diarrhea? What cells will you see in the stool? Is fever common? Is the volume large or small? What part of the GI tract is commonly affected?



Contrast all of this with non-inflammatory diarrhea.

How many microbes in the gut?



Which group is a major contributor to the gut microbiome? Which two types specifically?



Where are these organisms also present?

What two enzymes do anaerobes lack (this is why the growth of anaerobes is inhibited by oxygen)? What are these enzymes used to eliminate?



Do anaerobic infections stink? Does lack of a smell rule out anaerobes?

Anaerobic flora cause disease (abscesses) when they are introduced into normally _____ sites or when the balance of organisms is upset and pathogenic organisms _____.
Species found in _____ often reflect the normal flora in that site.
Anaerobic infections are often _____ (mixed anaerobic and facultative aerobic bacteria)
Environmental anaerobes also cause disease (tetanus, _____, gas gangrene)

Anaerobic flora cause disease (abscesses) when they are introduced into normally sterile sites or when the balance of organisms is upset and pathogenic organisms overgrow
Species found in abscesses often reflect the normal flora in that site.
Anaerobic infections are often polymicrobial (mixed anaerobic and facultative aerobic bacteria)
Environmental anaerobes also cause disease (tetanus, botulism, gas gangrene).

Bacteriodies fragilis:



Gram negative or positive?


Predominant organism in what part of the GI tract?


Most common cause of what?



What do infections usually arise from?


What is an important virulence factor?


What plays an important role in abscess formation?

What is the organism?

What is the organism?

Bacteriodes fragilis

Bacteriodes fragilis:



Clinical findings
Most frequently cause _____ infections –
_____ or peritonitis
Pelvic or peri-rectal _____, bacteremia, infected decubitus ulcers can occur
Found in about 25% of _____ abscesses
In general, B. fragilis causes disease below the _____ (lung abscess being the exception)
Enterotoxin producing strain can cause _____



Diagnosis: _____

Clinical findings
Most frequently cause intra-abdominal infections –
abscesses or peritonitis
Pelvic or peri-rectal abscesses, bacteremia, infected decubitus ulcers can occur
Found in about 25% of lung abscesses
In general, B. fragilis causes disease below the diaphragm (lung abscess being the exception)
Enterotoxin producing strain can cause diarrhea
Diagnosis
Anaerobic cultures

What is the treatment of Bacteroides fragilis?


What is it resistant to?

Treatment: metronidazole, carbapenems, combination beta-lactam/beta-lactamase inhibitors

Prevotella melaninogenica:



Gram positive or negative?


Where is it commonly found?


What type of pathogen? (opportunistic, etc)



What is the organism?

What is the organism?

Prevotella melaninogenica

Clostridium:



Gram stain? What type of rods?



It is the only anaerobic ______ forming bacteria. Resistant to what two things?



What two factors are responsible for pathogenesis?



Where is it found?

Describe what you see. What is the organism?

Describe what you see. What is the organism?

Large, "boxcar" gram+ bacilli


C. perfringens

Where is C. perfringens found? What is the clinical syndrome?

Found in soil and colon


Gas gangrene (discussed previously in septic arthritis/myositis lecture)

C. perfringens:



Food poisoning:
Important cause of _____ in the United States – 3rd most common _____ illness in the U.S.
Heat-resistant spores survive _____, then spores can germinate in foods such as meats, poultry or gravy at lower temperatures.
Following ingestion of large quantity of organisms, C. perfringens _____ (toxin) is produced in the GI tract
Outbreaks in _____ facilities have been described
8-16 hour incubation period characterized by watery diarrhea with _____; minimal vomiting. Resolves in _____ hours.

Food poisoning
Important cause of watery diarrhea in the United States – 3rd most common foodborne illness in the U.S.
Heat-resistant spores survive cooking, then spores can germinate in foods such as meats, poultry or gravy at lower temperatures.
Following ingestion of large quantity of organisms, C. perfringens enterotoxin is produced in the GI tract
Outbreaks in psych inpatient facilities have been described
8-16 hour incubation period characterized by watery diarrhea with cramps; minimal vomiting. Resolves in 24 hours.

Spore found in the soil. Portal of entry is usually a wound site (think nail penetrating foot). Can also be introduced during "skin-popping." What is the bacteria?

C. tetani

How is neonatal tetanus acquired (major problem in developing countries)?

Organism enters through contaminated umbilicus or circumcision wound

What is the pathogenesis of C. tetani?

Tetanus toxin (tetanospasmin, an AB neurotoxin), enters at neuromuscular junction => transported by motor neurons to ganglia.
 
Toxin binds irreversibly to ganglioside receptors => blocks release of inhibitory neurotransmitter (glycine and GABA) b...

Tetanus toxin (tetanospasmin, an AB neurotoxin), enters at neuromuscular junction => transported by motor neurons to ganglia.



Toxin binds irreversibly to ganglioside receptors => blocks release of inhibitory neurotransmitter (glycine and GABA) by cleaving action on membrane proteins (SNARE) involved in exocytosis



Net effect = disinhibition of neurons that modulate excitatory impulses from the motor cortex => increase muscle tone, painful spasms, and widespread autonomic instability.

Clinical presentation of Tetanus:
Characterized by strong muscle _____/spastic paralysis
_____ (lock jaw) first
Characteristic grimace known as _____
Exaggerated _____
Opisthotonos: pronounced _____ of the back due to spasm of the strong _____ muscles of the back
Respiratory _____ can occur
_____ mortality rate

Clinical presentation
Characterized by strong muscle spasms/spastic paralysis
Trismus (lock jaw) first
Characteristic grimace known as risus sardonicus
Exaggerated reflexes
Opisthotonos: pronounced arching of the back due to spasm of the strong ex...

Clinical presentation
Characterized by strong muscle spasms/spastic paralysis
Trismus (lock jaw) first
Characteristic grimace known as risus sardonicus
Exaggerated reflexes
Opisthotonos: pronounced arching of the back due to spasm of the strong extensor muscles of the back
Respiratory failure can occur
High mortality rate

Treatment of Tetanus:
Wound _____ to eradicate spores
_____ _____ immune globulin (HTIG) used to neutralize the toxin
_____ probably play a minor role but they are universally recommended
DOC = _____. Penicillin is an acceptable alternative
Tetanus _____ (does or does not) confer immunity following recovery from acute illness
All patients with tetanus should receive active immunization with a total of ____ doses of tetanus toxoid spaced at least ____ weeks apart with the 1st dose given immediately at diagnosis

Treatment
Wound debridement to eradicate spores
Human tetanus immune globulin (HTIG) used to neutralize the toxin
Antibiotics probably play a minor role but they are universally recommended
DOC metronidazole. Penicillin is an acceptable alternative
Tetanus does not confer immunity following recovery from acute illness
All patients with tetanus should receive active immunization with a total of 3 doses of tetanus toxoid spaced at least 2 weeks apart with the 1st dose given immediately at diagnosis

Different forms of botulism:


Type from canned foods (fruits, vegetables, and fish)


Type from inhalation or ingestion of spores in carpet or raw honey


Type from wounds


Type that would be an act of bioterrorism


Hospital form



How many cases are reported per year in the US? Most common type?



Why is there a rising incidence in California?

Cali = black tar heroin users
 
Babies = raw honey ingestion

Cali = black tar heroin users



Babies = raw honey ingestion

What is the pathogenies of C. botulinum?

AB toxins (8 antigenic types and the most potent bacterial toxins) => cleave SNARE proteins and proven the release of acetylcholine => flaccid paralysis

Clinical presentation
Acute, symmetric descending flaccid paralysis
Symptoms begin within 12-36 hours post-ingestion
Nausea, dry mouth, dysphagia, diarrhea, blurred vision
Paralysis descends to respiratory muscles, trunk and extremities
Possible death by respiratory failure


What is this the clinical presentation of?


What could have been done to prevent this?

Classic foodborn botulism



Spores resistant to heat => germinate after cooking and release toxin => subsequent heating will inactivate the toxin!

Are antibiotic recommended for infant botulism or for adults with suspected GI botulism? Why?

No! Lysis of intraluminal C. botulinum => increase amount of toxin available to absorption

What is another name for infant botulism?


What ages typically?



What are some components of the clinical presentation?

How do you treat botulism (think about paralysis of respiratory muscles, anti-toxins depending on ages, and antibiotic therapy for certain types)? How do you PREVENT botulism?

What is the organism?

What is the organism?

H. pylori

H. pylori:


Gram negative or positive, shape?


How do they move? Micro___philic.



What is the cytotoxin name? What type of secretion system? What rearranges the cytoskeleton? What enzyme is responsible for damage?

What leads to ulcers with H. pylori?



What are some methods of diagnosis? (think instruments, poop, breath, blood)



How do you treat H. pylori?