Week 2 - Gastrointestinal infections Flashcards

1
Q

To consider a diarrhea as invasive it needs to cross a layer of the intestinal lumen, which one is it?

A

Lamina propia

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2
Q

Bacteriemia signs and symptoms

A
  • Shivers
  • Piloerección
  • Marble skin
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3
Q

Salmonella spp. likes to invade an organ of the GIT, which one is it?

A

Gallbladder

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4
Q

Uncomplicated Salmonella (non typhi) is treated with what type of antibiotic?

A

None, since its uncomplicated adding an antibiotic will lead to Salmonella staying @ gallbladder

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5
Q

Principal cause of dysentery

A

Shigella dysenteriae

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6
Q

Bacterias that grow on SS agar

A
  • Salmonella (black bc of sulfhidric acid)
  • Shigella (transparent)
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7
Q

Patient with systemic manifestations (fever, chills, shivers) and inflammatory diarrhea needs lab tests, which ones?

A
  • Blood culture
  • Feces culture
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8
Q

Difference between food poisoning and an infection

A
  • Presence of fever in infection
  • Food poisoning has a shorter incubation period
  • Food poisoning only causes diarrhea, nausea and vomit but NO fever
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9
Q

Entamoeba histolytica doesn’t cause diarrhea and causes colitis, why tf?

A

Bc it affects the large bowel and NOT the small intestine

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10
Q

Resistant form of Entamoeba histolytic

A

Cysts (4 nuclei)

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11
Q

Why is blood and mucus seen at feces when infected with Entamoeba histolytic?

A

Bc it causes ulcers that bleed and produce mucus

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12
Q

Organs that can be invaded by Entamoeba histolytic

A
  • Liver
  • Lungs
  • Brain
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13
Q

Virulence factor present in Entamoeba histolytic

A

Lectin

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14
Q

Characteristics of enteric fever

A
  • Caused by Salmonella typhi
  • Febrile illness
  • Starts with fever, arthralgia, astenia, myalgia and general discomfort
  • 2 weeks later starts with inflammatory diarrhea
  • Bradycardia
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15
Q

Characteristic dermatological manifestation of enteric/ typhoid fever

A

Rose/ red exanthema rash at back

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16
Q

Zoonoses is caused by

A

Yersenia

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17
Q

Rotavirus is a…

A
  • Non-Enveloped | naked
  • RNA virus | double stranded
  • Double icosahedral capsid
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18
Q

Leading cause of dehydration due to enteritis (childhood and infants)

A

Rotavirus

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19
Q

The stomach flu is caused by…

A

Rotavirus

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20
Q

There are 8 strains of Rotavirus A-H, which one is the one associated with the “stomach flu”

A

Rotavirus strain A

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21
Q

Rotavirus is part of the reovirus family, and REO stands for…

A
  • R: respiratory
  • E: enteric
  • O: orphan
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22
Q

Rotavirus is transmitted via

A

Fecal-oral route (ingesting poop or vomit)
- Fluids
- Fingers
- Fields
- Flies

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23
Q

Clinical manifestations of Rotavirus

A
  • Gastroenteritis
  • Diarrhea (watery|malabsorption) and vomiting (acute onset)
  • Can lead to severe dehydration
  • Low grade fever
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24
Q

Complications of Rotavirus

A
  • Severe dehydration
  • Temporary lactose intolerance
  • Seizures when rotavirus is present @ CSF
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25
Q

Virus associated with intuception

A

Rotavirus

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26
Q

Pathogenesis of rotavirus

A
  • Infects epithelial cells @ small intestine
  • Causes malabsorption due to epithelial cell loss
  • Production of enterotoxin
  • Damage to Enteric Nervous System
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27
Q

Rotavirus decreases the activity of some digestive enzymes produced by the enterocytes, which ones?

A
  • Lactase
  • Maltase
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28
Q

Rotavirus’ production of… causes enterocyte death, leading to them being replaced by new loser underdeveloped enterocytes

A

Non-structural protein 4

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29
Q

Epidemiological characteristics of rotavirus

A
  • Universal infection during the first years
  • Can cause a severe sickness between 6M and 2 years old
  • 450,000 deaths in children
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30
Q

There aren’t any vaccines for Rotavirus (V/F)

A

False, there are 2 vaccines for rotavirus:
- Rotarix: monovalent vaccine
- RotaTeq: pentavalent vaccine
- Live attenuated oral vaccine

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31
Q

Reinfection is common throughout life when it comes to Rotavirus

A

True

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32
Q

Diagnosis for Rotavirus

A
  • Specific virologic diagnosis isn’t useful nor necessary
  • Antigen detected @ stool: enzyme-linked immuno-sorbent assay
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33
Q

Name of the specific treatment for Rotavirus

A
  • There isn’t any specific treatment
  • Hydration and supportive treatment
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34
Q

Why can’t someone infected with rotavirus take antidiarrheals

A

Bc it’ll slow down clearing of the virus

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35
Q

What kind of supplementation should you give to a patient with malnutrition that presents with Rotavirus

A

Zinc supplementation

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36
Q

Outer capsid proteins present in Rotavirus viral structure

A
  • VP8
  • VP5
  • VP7
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37
Q

Intermediate capsid proteins present in the Rotavirus viral structure

A

VP6

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38
Q

Enterobacteriacea characteristics

A
  • Gram -, non-spore forming
  • Facultative anaerobes (ferment glucose)
  • Coverts nitrate to nitrite
  • Produce catalase
  • Oxidase negative
  • Urease +
  • Grow on MacConkey agar
  • Some can ferment lactose (pink colonies)
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39
Q

Enterobacter virulence factors

A

Fimbriae

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40
Q

Which bacterias form part of the enterobacteriacea squad?

A
  • Salmonella
  • Escherichia coli
  • Proteus
  • Klebsiella
  • Citobacter
  • Yersenia
  • Shigella
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41
Q

Diagnosis techniques for enterobacteriacea

A
  • Standard culture
  • Immunoassays
  • PCR
  • Gel electrophoresis
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42
Q

Name the vaccine for all of these bacteriacea

A

There isn’t any vaccine

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43
Q

Enterobacteria that acts on the small intestine, causes traveler’s diarrhea, has a plasmid-mediated pathogenesis plus ST and LT enterotoxins

A

ETEC

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44
Q

Enterotoxins released by ETEC

A
  • Heat-labile enterotoxin
  • Heat stable enterotoxin

Inflammation @intestines - fluid @ intestinal lumen that then produces watery diarrhea

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45
Q

ETEC causes intestinal wall destruction, therefore bleeding

A

False

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46
Q

Enterobacteria that acts on the small intestine, causes infant diarrhea in developing countries (rare @USA), has a plasmid-mediated pathogenicity plus disruption on normal microvillus structure

A

EPEC

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47
Q

EPEC causes disease @ what specific age group

A

Children under 2 yo

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48
Q

What type of diarrhea does EPEC cause

A

Malabsorptive diarrhea because the cells flatten

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49
Q

Diagnosis for Traveler’s diarrhea (ETEC)

A

Commercial immunoassays

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50
Q

Diagnosis for EPEC

A

Characteristic adherence to Hep-2 or HeLa cells

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51
Q

Enterobacteria that acts on small intestine, causes infant diarrhea in developing/ developed countries, has a plasmid-mediated aggregative adherence to rods (shortening microvilli)

A

EAEC

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52
Q

Diagnosis for EAEC

A

Characteristic adherence to HeP-2 cells

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53
Q

Enterobacteria that acts on large intestine, starts with watery diarrhea and them followed by bloody diarrhea; pathology mediated by Shiga toxin plus destruction of microvilli

A

STEC

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54
Q

Diagnosis for STEC

A
  • Screening for O157:H7 with sorbitol-MacConkey agar
  • Immunoassays
  • DNA amplification assays
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55
Q

Enterobacteria that acts on large intestine, rare in developing and developed countries, that causes fever, cramping and watery diarrhea. Plasmid-mediated pathogenesis + destruction of cells lining the colon

A

EIEC

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56
Q

Where does EIEC replicate

A

Inside the intestinal lumen

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57
Q

Enterobacteria that can progress to hemolytic uremic syndrome

A

STEC

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58
Q

Enterobacteria that may progress to dysentery + bloody scant stools

A

EIEC

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59
Q

UPEC causes UTIs in what percentage

A
  • 90% of community acquired UTIs
  • 50% of hospital acquired UTIs
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60
Q

Does UPEC cause cystitis or polynephritis?

A

BOTH

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61
Q

Diagnosis for EIEC

A
  • Sereny test
  • Plaque assay in HeLa cells
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62
Q

Characteristics of E. coli

A
  • Gram -
  • Catalase +
  • Lactose fermentor
  • Facultative anaerobe
  • Encapsulated
  • Flagela
  • Grows in eosin agar
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63
Q

Antigens present in E. coli

A
  • O: somatic
  • K: capsular
  • F: fimbrial
  • H: Flagellar
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64
Q

K1 E. coli is associated with

A

Neonatal meningitis

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65
Q
  • Hemorrhagic colitis
  • Hemolytic Uremic Syndrome
  • Diarrheal outbreaks are all associated with what type of E. coli
A

E. coli O157:H7

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66
Q

Characteristics of a moderate fluid loss

A
  • Irritable children
  • Thirst: moderately increased
  • HR: elevated
  • BP: normal or slightly reduced
  • RR: elevated with deep inspiration
  • Eyes: sunken orbits
  • Capillary refill: delayed 2-3 seconds
  • Urine output: moderately decreased
  • Anterior fontanelle: sunken
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67
Q

Moderate fluid loss in percentage

A

6 to 9%

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68
Q

Characteristics of severe fluid loss

A
  • Lethargic
  • Children: irritable
  • Thirst: extreme but too lethargic to drink
  • HR: tachycardia or bradycardia
  • BP: hypotensive
  • RR: Kussmaul breathing
  • Eyes: deeply sunken orbits + NO tear production
  • Capillary refill: delayed > 3 seconds
  • Urine output: oliguria or anuria
  • Anterior fontanelle: markedly sunken
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69
Q

Severe fluid loss in percentage

A

> 10%

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70
Q

Enterobacteria that can ferment lactose

A

Escherichia coli

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71
Q

Which E. coli causes watery diarrhea + vomiting

A
  • EPEC: Enteropathogenic
  • ETEC: Enterotoxigenic
  • EAEC: Enteroaggregative
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72
Q

Which E. coli causes watery than bloody diarrhea

A
  • STEC: Shiga toxin-producing
  • EHEC: Enterohemorragic

FUN FACT: son lo mismo on god

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73
Q

Which enterobacteria can lead to a severe infection

A

EIEC (similar to Shigela)

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74
Q

What increases the risk of hemolytic uremic syndrome

A

Antibiotics

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75
Q

Where can E. coli grow (media cultures)

A
  • MacConkey’s agar (pink color)
  • Eosin methylene blue (green color)
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76
Q

Extra-intestinal infections caused by E. coli

A
  • Opportunistic pathogens
  • Commensals
  • UTI or neonatal meningitis
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77
Q

Mechanism of contagio of enterobacter

A
  • Endogenous: ppl who take a lot of antibiotics
  • Exogenous: direct/ indirect contact
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78
Q

“Coma shaped” gram - bacteria, that causes diarrhea even though it’s considered noninvasive

A

Vibrio cholerae

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79
Q

Microbiological characteristics of V. cholerae

A
  • Gram negative coma shaped
  • Oxidase positive
  • Grows @ alkaline media
  • Has a singular flagellum
  • Facultative anaerobe
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80
Q

Which V. cholerae causes epidemic cholera

A

O1 and O139

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81
Q

What causes the secretory diarrhea present in a Vibrio cholerae infection

A

Cholera toxin

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82
Q

V. cholerae has a reservoir, where?

A

Aquatic reservoir at brackish estuarine water

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83
Q

Mechanism of transmission for cholera

A

Fecal-Oral associated with unsafe water and inadequate sanitation

84
Q

Vibrio cholerae can cause 2 types of infections

A
  • Cholera: abrupt onset of watery diarrhea + vomiting
  • Gastroenteritis: milder form of diarrhea (O1 and non-O1 types)
85
Q

Diagnosis for cholera

A
  • Child ages 5> develops severe dehydration + acute watery diarrhea
  • Individual ager 2 or > develops acute watery diarrhea @ endemic area
  • Rapid antigen tests (dipstick stool assays)
86
Q

Gold standard agar to culture cholera

A

TCBS agar

87
Q

Management of cholera

A
  • Rapid assessment of the degree of dehydration
  • Fluid restauration
  • Oral rehydration/ IV fluid
  • Antibiotics
88
Q

What antibiotics can be used when treating cholera

A
  • Macrolides
  • Fluroquinolones
  • Also tetracyclines
89
Q

Primary role of the antibiotics when treating cholera

A
  • Secondary role
  • Decrease the duration of diarrhea
  • Limit secondary transmission
90
Q

Is there even a way to prevent cholera

A

2 oral vaccines approved or whatever

91
Q

The severe fluid loss leads to

A
  • Dehydration
  • Metabolic acidosis
  • Hypokalemia
  • Hypovolemic shock
  • Arrhythmia
  • Renal failure
92
Q

Characteristic diarrhea caused by V. cholerae O1 & O139

A

Rice water diarrhea

93
Q

Characteristic of the non-O1 strains of cholera that facilitates spread beyond intestine

A

Polysaccharide capsule

94
Q

Pathophysiology of cholera

A
  • Virulence factors: cholera toxin (CtxA and CtxB)
  • Vibrio cholerae attaches to ganglioside GMI receptor at the enterocytes
  • Cholera toxin gets endocytosed
  • Release of CtxA subunit to cytosol
  • Activation of adenylyl cyclase
  • Elevation of cAMP and produce a phosphorylation of CFTR
  • Efflux of ions (Cl- and Na+) and H2O
  • Causes diarrhea
95
Q

Cholera causes

A
  • Gastroenteritis
  • Watery non-inflammatory diarrhea
96
Q

Gram - rod part of enterobacteriaceae family that causes gastroenteritis

A

Salmonella spp.

97
Q

Gastroenteritis and other infections caused by nontyphoidal Salmonella (NTS)

A

Salmonellosis

98
Q

How many cases of salmonellosis are reported per year

A

1 million annually @ USA

99
Q

Nontyphoidal salmonellosis has a reservoir, where tf?

A

@ fresh and prepared food from animals

100
Q

There are some strains of Slmonella with multidrug resistance, to which antibiotic?

A

Fluroquinolones

101
Q

Pathophysiology of nontyphoidal salmonellosis

A
  • Ingestion of contaminated food and water
  • Invade intestinal epithelial cells (damage to lamina propia)
  • Causes: gastroenteritis or systemic infection
  • Salmonella can colonize liver, spleen and BM
  • From the liver it can pass to the gallbladder and lead to chronic carrige
  • Bacteria is shed to the small intestine due to bile secretion
  • Excreted at feces
102
Q

Diagnosis for Salmonella is done by…

A
  • Freshly passed stool cultured @ MacConkey agar
  • Blood cultures when suspected bacteriemia
103
Q

Salmonella and Shigella grow on SS agar, Salmonella grows in which color?

A

Black

104
Q

What antibiotic do you give to a patient with uncomplicated Salmonella gastroenteritis

A

None lol

105
Q

What antibiotics can you use for an invasive nontyphi salmonella severe gastroenteritis

A
  • Ceftriaxone
  • Fluroquinolones
106
Q

Salmonella can produce pathogenicity islands yes or no?

A

Yes slay

107
Q

When it comes to oxidase, fermentation and other stuff, where does Salmonella stand?

A
  • Oxidase negative
  • Ferments glucose but not lactose
  • Produces hydrogen sulfide
108
Q

Non-typhi salmonella spp attaches to which cells?

A

M cells located @ distal ilium

109
Q

M cells fagocite Salmonella nont and then…

A

Basically ingest them and spit them out @ Peyer’s patch (mucosal immune tissue)

110
Q

Once nont salmonella is @ Peyer’s patch it causes the release of pro-inflammatory cytokines and additional immune cells like neutrophils, this results in

A
  • Enterocolitis: inflammation of the intestines and colon
  • Damage @ mucosa when immune system cells are traveling causing ulcers… leading to efflux of water and causing diarrhea
111
Q

How can non t salmonella progress to bacteremia

A

If it crosses the lamina propia and reaches the blood vessels, reaching the liver, brain, bones and spleen

112
Q

Name some of the reservoirs for non-typhi salmonella

A
  • Infected humans
  • Birds
  • Reptiles
  • Mammals
  • Amphibians
113
Q

Transmission of non-typhi salmonella can be by the fecal to oral route and food borne, consumption of what increases the risk of salmonellosis

A
  • Contaminated raw/undercooked animal products
  • Poultry
  • Meat
  • Eggs
  • Unpasteurized milk and any other milk products
  • Contaminated: water, fruits and veggies, and peanut butter
114
Q

You need a really small amount of non-t salmonella to cause an infection

A

False, they are sensitive to stomach acid so a LARGE amount is needed

115
Q

Symptoms of non-t salmonella infection

A
  • Start within 24 to 48 hours
  • Watery diarrhea (maybe bloody)
  • Abdominal cramps
  • Low grade fever
  • Nausea and vomiting
  • Headache
  • Dehydration if fluids are not replenished
116
Q

Bacterial Inflammatory Enterides gang

A
  • Typhoid salmonella
  • Campylobacter
  • Yersenia enterocolitica
  • Escherichia coli O157
  • Clostridium difficile
117
Q

What characteristic will make you suspect of Clostridium difficile

A
  • History of antibiotic use
  • Recent admission to health care facility
118
Q

Inflammatory enteride that can cause an outbreak of bloody diarrhea + severe hemolytic-uremic syndrome

A

Enterohemorragic E. coli strain (EHEC)

119
Q

Inflammatory enteride that can cause intestinal and systemic infection

A

Campylobacter spp.

120
Q

Inflammatory enteride that has virulence factors like A and B toxin

A

Clostridium difficile

121
Q

Inflammatory enteride that causes seafood poisoning

A

Vibrio parahemolyticus

122
Q

Type of diarrhea caused by inflammatory enterides

A

Dysentery (blood, mucus and pus @ diarrhea)

123
Q

Inflammatory enterides cause intestinal inflammation, how can you spot that on a CBC?

A

Leukocytes and lactoferrin

124
Q

Inflammatory enteride that causes bacillar dysentery

A

Shigella dysenteriae

125
Q

Inflammatory enteride that causes amebian dysentery

A

Entamoeba hystolytica

126
Q

Inflammatory enteride that causes typhoid fever

A

Salmonella typhi

127
Q

Inflammatory enteride that causes yersiniosis

A

Yersenia enterocolitica

128
Q

Epidemiologicaly, what causes a Campilobacter jejuni infection

A

Animal and food exposure

129
Q

Epidemiologicaly, what causes a Clostridium difficile infection

A

Antimicrobials

130
Q

Epidemiologicaly, what causes salmonellosis

A

Food and reptile infection

131
Q

Epidemiologicaly, what causes a Shigella infection

A

Contact with an infected person or contaminated food

132
Q

Epidemiologicaly, what causes a Vibrio cholerae (O1 and O139) infection

A

Food and water exposure

133
Q

Epidemiologicaly, what causes a Yersenia enterocolitica infection

A

Food and water exposure

134
Q

Epidemiologicaly, what causes a Vibrio parahaemolyticus infection

A

Seafood exposure

135
Q

Bacillary dysentery is caused by

A
  • Shigella
  • 157 enteroinvasive E. coli
136
Q

Between Shigella and 157 enteroinvasive E. coli, which one is more infectious?

A

Shigellosis

137
Q

Microbiological characteristics of Shigella spp.

A
  • Gram - rods
  • Family: enterobacteriace
  • 100 to 200
  • Non-lactose fermenter
  • Urease and oxidase -
  • NO hydrogen sulfide gas
  • NO flagellum and NO spores
  • Grows on MacConkey agar
138
Q

Shigella is ingested and then travels to the intestinal lumen where it affects ____ cells and ____

A
  • Enterocytes
  • M cells
139
Q

After M cells fagocite Shigella…

A

They spit it up and it ends in the MALT tissue and causes apoptosis
- Causes inflammation and the release of cytoskines and immune cells
- Type III secretory system

140
Q

Toxin produced by S. dysenteriae serotype 1

A

Shiga toxin

141
Q

The presence of Shiga toxin @ blood circulation can lead to

A

Hemolytic uremic syndrome
- Hemolytic anemia
- Kidney failure (uremia)
- Trombocytopenia

142
Q

Virulence factors of Enteroinvasive E. coli

A
  • Possesses somatic antigen
  • Plasmid controls invasiveness
143
Q

Diagnosis for bacillary dysentery

A
  • Stools 4 Shigella infected ppl
  • The sooner the better
  • Plated on gram - media @ 37°C (overnight growth)
144
Q

Shigella causes dysentery that may last 7 days, what are the symptoms?

A
  • Abdominal cramping
  • Rectal cramping
  • High fever
  • Vomiting
  • Loss of appetite
  • Fecal incontinence
  • Dysentery: watery, mucous flaked diarrhea + blood + pus
145
Q

Antibiotics used for shigellosis (S. dysenteriae)

A
  • Adults: fluroquinolones for 3 days
  • Children: Cephalosporin, Ciprofloxacin or Azithromycin
146
Q

Pathogen responsible for causing amebiasis

A

Entamoeba histolytica

147
Q

Complications of amebiasis

A
  • Amebic colitis
  • Liver abscess
  • Brain abscess (maybe)
148
Q

How is Entamoeba histolytica transmitted

A
  • Fecal-oral
  • Person-person
  • Water/foodborne
149
Q

What is the correlation between amebiasis and children/ infants

A
  • Common in infants and children
  • Even more common in poor communities and in a developing world
150
Q

If a person is returning from an international travel, what will you suspect is causing their GIT infection (besides ETEC)

A

Amebiasis, common in returning international travelers

151
Q

Infectious form of Entamoeba histolytica

A

Cyst

152
Q

Therapy for invasive and noninvasive Entamoeba histolytica

A
  • Noninvasive: paromomycin
  • Invasive: metronidazole/ tinidazole
153
Q

Diagnosis for amebiasis

A
  • Fecal antigen detection or PCR
  • Colonoscopy and abdominal imaging
154
Q

Nonspecific febrile illness is also known as

A

Enteric fever

155
Q

What pathogen causes enteric fever

A

Typhoidal Salmonella

156
Q

What would make you suspect of enteric fever in a patient

A

Any patient with persistent unexplained prolonged fever with onset diarrhea

157
Q

Multidrug-resistant strains that cause enteric fever

A
  • Salmonella enterica typhi
  • Paratyphi A
158
Q

Typhi salmonella has ____ virulence factor that protects them from antibodies that signal leukocytes

A

VI capsular polysaccharide antigen virulence factor

159
Q

Symptoms of typhoid fever appear 1 or 2 weeks after infection, what are the symptoms?

A
  • High sustained fever
  • Abdominal pain
  • Constipation then diarrhea
  • Rose/salmon colored spots on chest/abdomen
  • Hepato and splenomegaly (when the infection spreads)
160
Q

Complications of enteric fever

A
  • Hemorrhage
  • Perforation
  • Encephalopathy
  • Shock
161
Q

Enteric fever can lead to

A

Chronic biliary carriage of Salmonella after resolution

162
Q

Enteric fever diagnosis

A
  • Blood culture
  • Bone marrow is more sensitive than a blood culture but IMPRACTICAL
163
Q

Therapy for enteric fever

A
  • Fluroquinolones
  • Azithromycin
  • Cefixime/ Ceftriaxone
  • Chloramphenicol
  • Amoxicillin
  • Fluid and electrolyte replenishment
  • NSAIDs
164
Q

Is there a vaccine for enteric fever or not?

A

Yes, oral attenuated typhoid vaccine and an injectable polysaccharide vaccine

165
Q

The suppression of neutrophils and high levels of monocytes and macrophages @ intestines cause…

A
  • Hypertrophy and necrosis
  • May lead to ileal perforation
  • May cause infection of the peritoneum
166
Q

Zoonoses with multiple animal hosts

A

Yersenia enterocolitica

167
Q

Yersenia enterocolitica has tropism for…

A

Lymph nodes

168
Q

Microbiology of Yersenia enterocolitica

A
  • Facultative anaerobe
  • Gram -
  • Rods/ Coccobacilli
  • Motile and non motile
  • Growth @ 37°C on MacConkey agar, Sheep blood agar, Salmonella-Shigella media (SS), CNS agar
  • Non-spore forming
  • Oxidase -
  • Non-lactose fermenter (white colonies)
169
Q

Yersenia enterocolitica has many virulance factors:
- ___ and ___ to attach to the epithelial cells @ intestines
- Type III secretion system (bacterial proteins ___)

A
  • Adhesins: YadA and Ail
  • YOPs: block pro inflammatory cytokines to avoid phagocytosis
170
Q

Where does Yersenia multiplicate

A

Peyer’s patches

171
Q

Loser enterotoxin produced by Y. enterocolitica

A

YST

172
Q

Natural hosts for Yesenia

A
  • Cows
  • Pigs
  • Deers
  • Birds
173
Q

Yersenia’s mechanism of transmission

A
  • Dog kk
  • Contaminated milk
  • Contaminated pork
174
Q

Clinical manifestations of Yersenia enterocolitica

A
  • Enteritis and pseudoapendicitis
  • Reactive arthritis or erythema nodosum
  • Terminal ileitis
  • Right colon: enterocolitis
  • Mesenteric lymphadenitis
175
Q

Patients at risk for developing septicemia by Yersenia

A
  • Immunosuppressive state ppl
  • Iron overload conditions: sickle-cell disease and beta-thalassemia
176
Q

Treatment for Yersenia enterocolitica

A
  • Aminoglycosides
  • Tetracyclines
  • Fluroquinolones
  • Streptomycin/ Gentamicin
177
Q

What is the role of antibiotics when it comes to enteritis or mesenteric lymphadenitis

A

None, lit es unnecessary

178
Q

Prevention for Yersenia enterocolitica

A
  • Safe handeling/preparation of pork
  • Avoid unpasteurized milk and dairy products
179
Q

Campylobacter jejuni characteristics

A
  • Small, curved, gram - rods
  • GIT illness (1 to 7 days)
  • Bloody diarrhea + abdominal pain
180
Q

Seasonal changes in regards to the presence of Campylobacter jejuni

A
  • Summer and fall: developed countries
  • All year round: developing countries
181
Q

How does someone come in contact with Campylobacter jejuni?

A

Consumption/ handling of poultry + unpasteurized milk

182
Q

Microbiological characteristics of Campylobacter jejuni

A
  • Thrive @ 42°C
  • Very small
  • Microaerophilic and grow best @ 5-10% of oxygen
  • Gram - bacteria
  • Flagellum
  • Oxidase +
  • Loves warmth
183
Q

Isolation of… can help with the diagnosis of Campylobacter jejuni

A

Stool or blood

184
Q

Therapy and treatment for Campylobacter jejuni

A
  • Replace fluids + electrolytes
  • Antibiotics: Erythromycin and extended-spectrum macrolides
185
Q

Role of the antibiotics in a Campylobacter jejuni infection

A

To shorten the duration of the symptoms

186
Q

Campylobacter jejuni are so tiny they can filter from stool sample

A

yuh

187
Q

Virulence factors for Campylobacter jejuni

A
  • Endotoxin
  • Polysacchharide capsule
  • Flagella
  • Cytolethal distending toxin
  • Filaments (PEB1 and CadF)
188
Q

Syndrome related to Campylobacter jejuni

A

Guillian-Barré syndrome

189
Q

Campylobacter jejuni causes…

A
  • Fever, muscle pain, malaise and headache
  • Reactive arthritis
  • Gastroenteritis @ mucosa of jejunum, ileum and colon
  • Extraintestinal infections: bacteriemia and cardiovascular
190
Q

Autoimmune disorder that affects the peripheral nervous system and causes demyelination

A

Guillian-Barré

191
Q

Manifestations of Guillain-Barré syndrome

A
  • Hyporeflexia
  • Normal WBC
  • Elevated protein
  • Prolonged F waves
  • Demyelination
  • Ascending paralysis
192
Q

Gram - bacterium that colonizes the stomach and increases risk of developing PUD

A

H. pylori

193
Q

Microbiological characteristics of H. pylori

A
  • Urease, oxidase and catalase +
  • Gram -
  • Spiral-shaped
194
Q

Diagnosis of H. pylori

A
  • Noninvasive: serology, urea breath test and stool antigen
  • Invasive: endoscopy and analysis of gastric tissue
195
Q

Treatment for H. pylori

A

Triple or quadruple therapy

196
Q

Virulence factors for H. pylori

A
  • Urease: converts urea to ammonia and bicarb to neutralize gastric secretions
  • Endotoxin (LPS)
  • Exotoxins: VCA and CAGA
197
Q

H. pylori can cause…

A
  • Gastritis: @ pyloric antrum
  • Peptic ulcers: gastric and duodenal
  • Gastric adenocarcinoma: metaplasia
198
Q

Besides the rice water diarrhea, V. cholerae causes fever, cramping and pain

A

False, it does not cause any of those

199
Q

The severe dehydration caused by V. cholerae can result in…

A
  • Disorientation
  • Dry mouth
  • Swollen tongue
  • Sunken eyes
  • Cold + clammy skin
  • Shriveled/ dry hands and feet
200
Q

Low levels of which electrolyte cause metabolic acidosis and kussmaul breathing (V. cholerae infection)

A

HCO3

201
Q

Low levels of which electrolyte cause muscle dysfunction (cramps, weakness, abnormal heart rhythms) (V. cholerae infection)

A

K+

202
Q

Low levels of which electrolyte cause headaches, poor balance, disorientation, seizures and possibly coma

A
  • Na+
  • Cl-
203
Q

Which microorganism grows on Thiosulfate-citrate-bile salts-sucrose agar

A

Vibrio cholerae

204
Q

Mechanism of transmission of Campylobacter jejuni

A

Fecal-oral

205
Q

Bacteria most commonly associated with toxic megacolon

A

Campylobacter jejuni