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Flashcards in STEP 1 Gram Negative Bacteria 1 Deck (51)
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31

What is the toxin and mechanism of EIEC? This is similar to which other microbe?

Microbe invades INTESTINAL mucosa and causes NECROSIS and INFLAMMATION

Similar to SHIGELLA

32

What is the presentation of EIEC?

Invasive; dysentery

33

What is the toxin and mechanism of ETEC?

Produces HEAT-LABILE and HEAT-STABLE ENTERTOXINS

No inflammation or invastion

34

What is the presentation of ETEC?

Traveler's diarrhea (watery)

35

What is the toxin and mechanism of EPEC?

NO TOXIN produced

Adheres to apical surface, FLATTENS VILLI--> prevents absorption

36

What is the presentation of EPEC?

Diarrhea, usually in children (P for pediatrics)

37

What is the most common serotype of EHEC?

O157:H7

38

What toxin does EHEC produce? What does this toxin cause? What is the triad of this syndrome

EHEC produces the SLT (Shiga-like toxin)

Causes Hemolytic-Uremic Syndrome (HUS)

HUS: Anemia, thrombocytopenia, and acute renal failure

39

What is the pathogenesis of hemolysis, decreased renal blood flow, and thrombocytopenia caused by EHEC?

1. Microthrombi form on endothelium damaged by SLT. This causes mechanical hemolysis (schistocytes form) and decreased renal blood flow

2. The microthrombi also consume platelets--> thrombocytopenia

40

Where does Klebsiella normally reside? What is it known for causing in alcoholics and diabetics?

Intestinal flora

Causes atypical lobar pneumonia when aspirated

41

Klebsiella has abundant polysaccharide capsules...what does this cause? What does Klebsiella sputum look like?

Very MUCOID colonies

Red "currant jelly" sputum

42

Klebsiella is also known to cause what (3) besides pneumonia?

1. Abscess in lungs

2. Abscess in liver

3. Nosocomial UTIs

43

What are the 4 A's of Klebsiella (one is a stretch)

Aspiration pneumonia

Abscess in lungs and liver

Alcoholics

di-A-betics (told you it was a stretch)

44

Salmonella:

Flagella? 

Spread throughout the body?

Animal reservoirs?

**Hydrogen sulfide production?

**Antibiotic effects on disease?

Invades where in the body?

Bodily response?

Bloody diarrhea?

**Lactose fermentation?

Salmonella:

HAS flagella

HEMATOGENOUS spread

MANY animal reservoirs

**PRODUCES hydrogen sulfide

**Antibiotics PROLONG fecal excretion of organism

Invades INTESTINAL mucosa and causes a MONOCYTIC response

CAN cause bloody diarrhea (not often)

**DOES NOT ferment LACTOSE

45

Shigella:

Flagella

Spread throughout the body

Animal reservoirs

**Hydrogen sulfide production

**Antibiotic effects on disease Invades where in the body?

Bodily response?

Bloody diarrhea

**Lactose fermentation

Shigella:

NO goddamn flagella

CELL TO CELL transmission;

no hematogenous spread

Only reservoir are HUMANS and PRIMATES

**DOES NOT produce hydrogen sulfide

**Antibiotics SHORTEN fecal excretion of organism

Invades INTESTINAL mucosa and causes a PMN response

OFTEN causes bloody diarrhea

**DOES NOT ferment lactose

46

E. Coli algorithm findings: gram shape lactose

E. Coli is a gram negative rod FAST fermenter of lactose

47

Pseudomonas algorithm findings gram shape lactose oxidase

Gram Negative Rod Lactose negative Oxidase positive

48

Shigella algorithm findings

Gram negative rod Negative lactose Negative oxidase H2S -

49

Salmonella algorithm findings

Gram negative rod

Lactose negative

Oxidase negative

H2S +

50

Salmonella typhi causes what? Found only in which animal?

Salmonella typhi causes Typhoid Fever Only found in humans

51

Salmonella typhi is characterized by what (4)? symptoms How to become a carrier?

Rose spots on abdomen

Fever

Headache

Diarrhea

 

Can remain in gallbladder causing a carrier state