MICRO Flashcards

1
Q

H pylori is associated with what longterm complications?

A

Chronic gastritis
Adenocarcinoma
MALTomas

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2
Q

What are the VFs for H pylori?

A

Vac A-> vaculating cytotoxin
PAI-> encodes Type III secreting system
Cag-> rearranges cytoskeleton
Urease

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3
Q

Which of the H pylori VFs causes gastritis and adenocarcinoma?

A

Urease-> gastritis

Cag- Carcinoma

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4
Q

What are the diagnostic tests for H pylori?

A

Biopsy-> culture
Urea breath test
Serology= Good for treatment and recovery

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5
Q

Most common bacterial GI infection in developed countries, caused by Uncooked Poultry and unpasteurized milk?

A

Campylobacter jejuni

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6
Q

Spiral shaped G- rod, that causes fever, **Appendicitis like lower abdominal pain,
Watery diarrhea progresses to Bloody/Pus diarrhea?

A

Campylobacter jejuni

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7
Q

What is the sequelae for C jejuni infection (Pg)?

A

X-reactive antibodies to Cj lipooligosaccharides cross react with Myelin= Guillain- Barre

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8
Q

Curved G- Rod
Oxidase +
Motile
Found in saltwater?

A

Vibrio (cholera)

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9
Q

Infection associated with poor sanitation, contaminated water/food, >200 serogroups based on O-antigen (O1 & O139 responsible for pandemics)?

A

Vibrio cholera

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10
Q

2-3 days post infection, abrupt onset of Vomiting, HIgh volume Watery diarrhea, eventual death by Dehydration?

A

V cholera–> cholera toxin activates Adenylyl cyclase

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11
Q

High volume “Rice water stools?”

A

V cholera

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12
Q

What are the VFs for cholera?

A

PAI-> encoded pilus for attachment

Phage encoded toxin

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13
Q

Toxin causes ADP ribosylation of GTP-binding protein and activates adenylyl cyclase causing Secretory diarrhea. What is the Dx tests for the organism?

A

Cholera toxin-> Culture on TCBS (thiosulfate citrate bile salts sucrose) or MacConkey agars

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14
Q

What are the culture medians used to diagnose cholera?

A

TCBS

MacConkey agars

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15
Q

Found in sea-water and SEAFOOD poisoning, MC food born illness in Japan, causing watery diarrhea, Cramps, N/V, **24hrs after exposure?

A

Vibrio parahaemolyticus

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16
Q

Found in sea water, infection through RAW Oysters, causes Cellulitis, vomiting, diarrhea, Bullae and septicemia in Immunocomprimised patients?

A

V vulnificus (BULLAE)

**highly fatal (20%)

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17
Q

What are the characteristics of Anaerobic infections/bacteria?

A

Lack SOD and Catalase negative
STINKY PUS
Smelly breath
Abscess + tissue necrosis

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18
Q

Pt with foul smelling breath and GI infection. What is the most likely characteristic of the infection?

A

Caused by Anaerobic bacteria

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19
Q

G- coccobacillus with Anti-phagocytic capsule, most common anaerobic infection causing abscesses, PID, and pulmonary infections?

A

Bacteriodes fragilis

**PID + GI

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20
Q

G- coccobacillus + anti-phagocytic capsule

Opportunistic abscess, pulmonary and Periodontal infections?

A

Prevotella melaninogenica

**Periodontal + GI

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21
Q

G+ anaerobic spore forming Rods
resistant to high heat + harsh environments
Exotoxins and secrete Hydrolytic enzymes?

A

Clostridium

**ONLY anaerobic spore forming Rod

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22
Q

Large Boxcar G+ Rods
Found in soil and intestines
Cause GAS GANGRENE + cellulitis + food poisoning?

A

Clostridium perfringens

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23
Q

Contamination of wounds by spores causes necrosis and gas formation?

A

C perfringes Gas gangrene

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24
Q

Enterotoxins found in Meats at low temp allowing spores to germinate, causes Nausea, diarrhea, pain, NO Fever or Vomiting within 8-24hrs?

A

C perfringens food poisoning

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25
Q

AB neurotoxin entering Neuromuscular junction and transported by motor neurons to ganglia, Cuts V-snare?

A

C tetani (tetanus toxin)

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26
Q

What is the action of Tetanus toxin?

A

Cuts V-snare
Vesicles and Neurotransmitters cant fuse with membrane
Prevents Release of Inhibitory NT (GABA and glycine)

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27
Q

What bacterial toxin inhibits the blocking of postsynaptic inhibition of spinal motor reflexes (GABA)?

A

Tetanus toxin

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28
Q

What are the signs and symptoms of Tetanus infection?

A

TRISMUS (Lock Jaw)
Risus sardonicus= facial spasma causing a GRIN
Spasms
Death via exhaustion and Respiratory failure

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29
Q

What is the treatment for tetanus poisoning?

A

HTIG to soak up the excess toxin

Sedate to avoid exhaustion and allow for new axon generation

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30
Q

Trismus + V-snare?

A

Tetanus toxin

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31
Q

Most toxic bacterial exotoxin
Cleave V and T snare
Prevents ACh release?

A

Botulinum toxin

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32
Q

Bacterial spores are resistant to heat and germinate after cooking, toxins are heat labile, but infection causes ACUTE symmetric descending Flaccid Paralysis?

A

Botulism

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33
Q
Pt with symptoms 12-36hrs post infections from food contaminated with spores, presents with Nausea 
Dry mouth
Diarrhea
Blurred vision 
Respiratory failure?
A

Botulism = Inhibits ACh release

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34
Q

“Floopy baby” syndrome, infants 3wks-8mo, causing constipation, poor muscle tone, and feeding problems?

A

infant Botulism

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35
Q

Most common nosocomial infection causing diarrhea post-antibiotic therapy?

A

C difficile

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36
Q

What are the actions of C difficile Toxins A and B?

A

A (enterotoxin)= Diarrhea

B (Cytotoxin)= Inflammation

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37
Q

bacterial infection if hospitalized pt causing Fever, Watery diarrhea -> bloody
and presences of pseudomembranous colitis. What are the diagnostic tests and treatment for this infection?

A

Dx: Tox B from stool culture
RADT fro Tox A & B in stool

Rx; Discontinue antibiotics

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38
Q

Causes Persistant Gi infection?

A

H pylori

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39
Q

Food borne infection + Watery to bloody diarrhea?

A

C jejuni

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40
Q

Watery diarrhea + Food borne + seasonal?

A

V cholera

V parahaemolyticus

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41
Q

Normal flora + Nosocomial infections?

A

B fragilis

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42
Q

Normal flora + watery diarrhea?

A

C perfringes

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43
Q

Flaccid paralysis ?

A

Botulism

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44
Q

Watery diarrhea + Normal flora + nosocomial infections?

A

C difficile

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45
Q

What organisms can cause watery diarrhea?

A

V cholera + parahaemolyticus
C perfringens
C difficile

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46
Q

Can cause Watery–> Bloody diarrhea?

A

C jejuni

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47
Q

Food borne GI infections?

A

C jejuni
Vibrio
C perfringens

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48
Q

Opportunistic infections caused by normal flora?

A

B fragilis

C difficile

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49
Q
G- facultative anaerobe
Ferments glucose
Oxidase negative
Nitrates--> Nitrites
Motile by peritrichous flagella?
A

Enterobacteriaceae

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50
Q

What is a MacConkey agar?

A

Selective and differential media
Contains chemicals that inhibit G+ organisms
pH indicator= red->yellow when <6.8
Lactose fermentators can cause color change(Ecoli)

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51
Q

80-90% of diarrheas in USA are caused by?

A

VIRUSES

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52
Q

Describe non-inflammatory diarrhea?

A

Watery + HIGH volume
Due to ENTEROTOXIN acting on Ion channels
NO fever
NO fecal leukocytes

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53
Q

Describe Inflammatory or invasive diarrhea?

A
LOW volume 
Cytotoxin induced
Feces + for Methylene blue and lactoferrin (WBC)
FEVER
Dysentery 
BLOOD + Mucus in Feces 
TENESMUS= painful spasms of anal sphincter
>2wks= parasite
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54
Q

What agents usually cause diarrhea in AIDS patients?

A

Cryptosporidium
Mycobacterium avium
CMV

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55
Q

What tests are performed to identify the causative agent of diarrhea?

A

Culture
Rapid Ag Detection Tests (RADTs) for viruses/toxin
Microscopic exam for parasites

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56
Q

What is contraindicated in patients with Enterohemorrhagic E coli Dysentery?

A

Antibiotic treatment

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57
Q

What is the complication of EHEC induced diarrhea?

A

HUS

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58
Q

What is the complication of C jejuni induced diarrhea?

A

Guillian Barre

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59
Q

What organisms are associated with Reiter’s syndrome (polyarthritis + conjunctivitis + urethritis) as complications of diarrhea?

A

Shigella
Campylobacter
Yersinia
Salmonella

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60
Q

Lac +
Femrents Glucose with H2
Does NOT produce H2S
Motile?

A

E coli

  • *salmonella= H2S +
  • *Shigella= H2S - & NO gas (H2)
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61
Q

What strain of E coli causes Hemorrhagic colitis with Sudden onset of Severe abdominal cramps and Watery diarrhea that is Bloody within 24hrs?

A

Enterohemorrhagic E coli (EHEC)

**O157:H7

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62
Q

4 yo child with Bloody diarrhea for 1-8 days
NO Fever and absent leukocytes
Anemia and Thrombocytopenia. What is the most likely complication?

A

HUS–> acute kidney failure

**MCC of pediatric acute renal failure

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63
Q

What symptoms are complications are associated with E coli O157:H7?

A

HUS–> acute renal failure

  • *Seizures + Strokes
  • *Anemia + Thrombocytopenia
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64
Q

Child with Anemia, Thrombocytopenia, and uremia, possibly seizures?

A

HUS–> EHEC infection

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65
Q

Reservoir is cattle but does not cause infections in cattle, Major source of human infection is GROUND BEEF, unpasteurized milk, and juice, lettuce, or salami. Can also spread in child care centers?

A
EHEC
**Recent outbreaks associated with: 
Spinach
Unpasteurized juice
Alfalfa sprouts
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66
Q

What are the VFs for EHEC (O157:H7)?

A

Enterotoxin= Shiga-like Toxins
**Inhibits protein synthesis and results in cell death–> disseminates to Kidneys
Pathogenicity island= Type3 secretion system
LEE PAI= Causes diarrhea

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67
Q

What are the diagnostic tests for EHEC (O157:H7)?

A

Sorbitol MacConkey agar
**O157:H7 is Sorbitol negative but Normal Ecoli is Sorbitol +
RADT for Shiga Toxins in stool

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68
Q

What organism is the leading cause of bacterial diarrhea and TRAVELERS diarrhea?

A

ETEC (enterotoxigenic E coli)

**contain enterotoxins and fimbriae

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69
Q

What type of E coli cannot ferment Sorbitol?

A

EHEC O157:H7

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70
Q

Causes noninflammatory HIGH volume diarrhea similar to cholera. Contains 2 VFs: LT and ST?

A

ETEC

  • *LT= heat labile= Acts just like Cholera toxin
  • *ST= heat stable= increases cGMP-> cAMP
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71
Q

What G- rod organism has a AB toxin that binds ganglioside receptors and enzymatically activates adenylyl cyclase leading to Chloride efflux?

A

ETEC= LT TOXIN

**Cholera Like toxin

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72
Q

WHat is the function of ST toxin of ETEC?

A

Binds Guanylyl cyclase receptor= activates PKA
Increased cAMP = activation of CFTR
Diarrhea

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73
Q

What type of E coli resembles Cholera and Shigella?

A
Cholera= ETEC
Shigella= EIEC
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74
Q

E coli serotype that causes Dysentery-like diarrhea and fever. organism lacks fimbrial adhesions and does not produce LT or ST toxins, NON motile and LAC-?

A

EIEC

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75
Q
E coli strain with:
Fimbrial adhesions (CFA1&2)
LT & ST toxins
Watery diarrhea in infants/travelers= NO fever
High infectious dose?
A

ETEC

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76
Q
E coli strain with:
Nonfimbrial adhesins
penetrates and multiply in epithelial cells
NO Shiga Toxin
Dysentery like Diarrhea + FEVER?
A

EIEC

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77
Q

E coli strain with:
Intimin adhesin proteins
EAF binds to intestinal cells
Infantile diarrhea?

A

EPEC

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78
Q

E coli strain with:
NO characterized adhesins
ST like toxin and Hemolysin
Persistant diarrhea in Young children?

A

EAEC

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79
Q
E coli strain with:
Fimbrial adhesin
Phage coded Shiga toxin
Copious bloody diarrhea + intense inflammation
MCC of hemorrhagic colitis in US
LOW INFECTIOUS DOSE?
A

EHEC = causes HUS

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80
Q

What is the function of K antigen in UPEC?

A

Polysaccharide capsule protects against Phagocytosis by PMNs + Ab and complement deposition
K-1= antiphagocytic and antigenic disguise

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81
Q

What is the major E coli VF that causes neonatal Meningitis?

A

K-1 antigen = Homopolymer of sialic acid

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82
Q

Lac-
Ferments Glucose + H2 gas formation
H2S + ?

A

Salmonella

**only difference with E coli is Lac (+)

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83
Q

What are the sources of Salmonellosis infections?

A

Poultry
Eggs
Reptiles
Turtles

84
Q

Pt with N/V, abdominal cramps, and diarrhea 20-72hrs post infection. Bacteria enters M cells in the distal small intestine or proximal colon and is localized within Macs in the Lamina propria?

A

Salmonella (enteritidis or typhimurium)

85
Q

Enteric Febrile infection caused by dissemination of a bacterial parasite. Longterm infection carried in the Gallbladder because organism is phagocytosed but NOT killed in Macs. Eventually can cause Splenic rupture?

A

Salmonella typhi

86
Q

Patient with headache, HIGH fever, confusion, slow pulse, and skin rash. NO diarrhea. What are VFs for this organism?

A

S typhi VFs=
T3 secretion system
LPS
Vi ag (capsule)

87
Q

What is the treatments available for S typhi?

A

Antibiotics

Live attenuated Vaccine

88
Q

What is th cause of 70% of dysentery shigellosis in children in US?

A

Shigella sonnei

89
Q

Describe the Pathogenesis of shigellosis?

A

Shigella enters into Microfolds cells
Escapes from Phagocytic vesicles
Uses polar actins to burrow into neighboring cells

90
Q

Child with watery diarrhea, abdominal pain, then becomes bloody with Mucus/Pus. Along with Severe cramps and tenesmus. Fecal sample shows Sheets of leukocytes?

A

Shigellosis

91
Q
Lac - 
No H2 from Glucose 
NON motile 
H2S - 
Cytotoxin causes protein inhibition by cleaving 28rRNA?
A

Shigella

92
Q

What two Gi organisms produce HIGH amounts of cytotoxins and can Cause HUS?

A

EHEC

Shigella dysenteriae

93
Q

What bacterial diarrheal infection presents with LLQ pain?

A

Yersinia enterocolitica = Mimics Appendicitis

94
Q

Opportunistic heavily Capsulated pathogen that causes Aspiration pneumoniae in Alcoholics or Neutropenics?

A

Klebsiella

95
Q

Highly necrotic pneumoniae and “Current Jelly” sputum?

A

Klebsiella

96
Q

Opportunistic pathogen causing Pneumoniae with BRICK RED colonies?

A

Serratia marcescens

97
Q

Nosocomial/ post antibiotic Diarrhea. Urease producing organism that increases pH of urine and causes UTIs leading To STONE formation. Culture shows SWARMS and Antigens are used is Rickettsiae (Weil-Felix Test)?

A

Proteus (vulgaris)

98
Q

Which bacterial species require LOW # of cells for infection?

A

C jejuni
EHEC
Shigella

99
Q
What results are seen on KIA for:
E coli?
Shigella?
Proteus?
Pseudomonas?
A
  1. E coli= Entirely Yellow (Lac+) + Bottom gap (H2+)
  2. Shigella= Red Top (Lac-) + Y bottom (Gluc +) + No gap (H2-)
  3. Proteus= Entirely Black (H2S +)
  4. Pseudomonas= All Red no gaps or black (No fermentation or gas)
100
Q

Pt with persistent week long diarrhea. MCC?

A

parasite = Giardia

101
Q

What is the reason Resident E coli do not cause diarrhea?

A

Lack VFs = PAIs

102
Q

Describe the Pathogenesis of EPEC infections?

A
  1. Pili binds enterocyte
  2. T3 system injects cell with Receptor
  3. Bacteria binds Receptor
  4. causes cytoskeletal changes
103
Q

What lysogenic phage encoded toxin cleaves 28S rRNA and what bacteria secrete it?

A

Shiga toxin

Shigella + EHEC

104
Q

What is the function of EHEC Locus Enterocyte Effacement (LEE)?

A
PAI 
T3 secretion system
Delivers E coli to host receptor
Pedestal formation 
RESPONSIBLE for Diarrhea
105
Q

Why is antibiotic therapy Contraindicated in EHEC infections?

A

Exacerbates HUS

106
Q

Causes High volume Travelers diarrhea by way of LT toxin?

A

ETEC

**CFA I & II for attachment

107
Q

Lac - and non motile (similar to shigella) Dysentery causing E coli that affects children <5yo?

A

EIEC

108
Q

What is the pathogenesis of the spread of Shiegella and EIEC infections?

A

Invasion of enterocyte
Form Actin tail
Push through the cell membrane into adjacent cell

109
Q

Causes watery infant diarrhea and loss of Brush boarder and microvilli. Pedestal formation via LEE?

A

EPEC

110
Q

Infection of small bowel, T3 secretion inject effector M cells that form membrane “Ruffles” and cause endocytosis of bacteria. Once through BM they infect and KILL MACS?

A

Salmonella enteritidis

111
Q

What is the function of the Vi capsule antigen on S typhi?

A

inhibits PMN phagocytosis

112
Q

What is the DOC for the treatment of a disseminated bacterial infection that kills via Splenic Rupture?

A

Salmonella Typhi = Ceftriaxone

113
Q

What is MCC of severe diarrhea in INFANTS and young children Worldwide?

A

Rotavirus (Reoviridae)

114
Q

Describe the genome of the Rotaviruses?

A

NON enveloped particles (double shelled)
SEGMENTED
DS RNA
Only 4 G-P combinations cause 90% of human infections

115
Q

What is the basis for development of vaccines for Rotaviruses?

A

ONLY 4 G-P combinations cause >90% of human infections

116
Q

Describe the replication process of Rotaviruses?

A
  1. Virus endocytosed
  2. Capsid proteins Proteolytically processed-> produce infectious subviral particles
    * *3. CORE released into Cytoplasm= synthesizes mRNA
  3. Assembly of virus in cytoplasm
  4. Release via cell lysis
117
Q

Major cause of foodbrone epidemic acute gastroenteritis in Older children and adults?

A

Noroviruses (Norwalk)

118
Q

Young (1-2yo) child with severe diarrhea. MCC?

A

Norwalk virus

119
Q

MCC of community based outbreaks of nonbacterial gastroenteritis in School aged children and adults?

A

Norwalk virus

120
Q

What are some of the sources of Norwalk outbreaks?

A

Food (shellfish, frosting, salads)

Cruise SHIPS

121
Q

How would a person with a Norwalk infection most likely present?

A
Nausea 
Vomiting 
Diarrhea
Fever
Dehydration
122
Q

What is the pathogenesis for the inflammatory diarrhea caused by Norwalk viruses?

A

Infects Villus epithelium of small bowel
Replication = cell lysis
Loss of epithelial cells= Functional alterations
Glucose coupled Na transport is Impaired= diarrhea

123
Q

WHat is the bases for the watery diarrhea seen in a patient with a norwalk virus infection?

A

Impaired Glucose coupled Na absorption in the small intestine= Inflammatory diarrhea due to Loss of cells
**Adenylate cyclase and cAMP not affected

124
Q

What is the difference between the antibody production against Rotavirus vs. Noroviruses?

A
Rota= Abs obtained EARLY in life 
Noro= Gradual/increase steadily over persons life
125
Q

What are the ways to prevent/treat Rotavirus infections?

A

Hydration therapy (ORT)
RotaTeq-> Pentavalent bovine/human Live attenuated vaccine
Rotarix-> human monovalent life attenuated vaccine
**NOrwalk virus–> NO vaccines

126
Q

What are the genomic characteristics of Enteroviruses?

A

NON enveloped (STABLE)
+ RNA
Acid stable
Replicate @ 37 degrees

127
Q

Which type of enterovirus causes flaccid paralysis (wheel chair)?

A

Poliovirus

128
Q

Enterovirus that causes myocarditis and pericarditis?

A

Coxsackievirus

129
Q

What is significant about the replication of Enteroviruses?

A

Similar to Rhinovirus-> Protease cleaves mRNA with 5 cap

  • *Replicate in lymphoid of URT and GUT
  • *Asymptomatic infections
130
Q

Pt complains of fever, malaise, headache, nausea, abdominal pain then develops muscle weakness and CONFUSION. What should be tested?

A

CSF–> Bacterial or Viral Meningitis

**Enteroviruses cause Meningitis

131
Q

Pt with abrupt onset of fever and chest describes as substernal and spasmodic. What virus will most likely be cultured from this patient?

A

Coxsackie group B

132
Q

Pt with ulcerative lesion in mucosa of the mouth followed by vesicular lesions on the soles and palms. What virus is most likely responsible?

A

group A16 Coxsackie

  • *Hand Foot and Mouth disease
  • *Hemorrhagic conjunctivitis
133
Q

Which virus family is NON segemented ss + RNA that causes meningitis, pleuritis, and skin lesions on soles/palms?

A

Picornaviridaee viruses

  • Coxsackie
  • Enteroviruse
  • Echovirus
134
Q

What is the genome for virus family responsible for most of the severe diarrhea in INFANTS and children?

A

Rotavirus–> SEGMENTED ds RNA

135
Q

Non segmented ss + RNA virus responsible for most of the food-borne epidemics of acute gastroenteritis in YOUNG children and adults?

A

Norwalk virus

136
Q

What is special about the genome of Rotaviruses?

A

Segmented–> Reassortment= Antigenic diversity

**Similar to Influenza virus

137
Q

What are the similarities between Rotaviruses and Norwalk viruses?

A

Fecal-Oral transmission
Nonenveloped = Very stable
Very Infectious–> 10-100 particles
Hand washing is preventative

138
Q

Young child with nausea, fever, Watery diarrhea, no leukocytes in stool, and prominent Vomiting?

A

Norwalk infection

139
Q

What is the simple pathogenesis for the “Watery diarrhea” seen in Norwalk infections?”

A

Loss of Microvilli in small and large intestines due to cell death= loss of Glu/Na cotransporters

140
Q

Enterically-transmitted “infectious” hepatitis?

A

HAV

141
Q

Parentarally transmitted “serum” hepatitis?

A

HBV

142
Q

Dependent upon coinfection hepatitis virus?

A

HDV

143
Q

Which hepatitis virus is related to poliovirus and Coxsackie viruses?

A

HAV (Picornovirus)

144
Q

Acute hepatitis, Fecal oral transmission, and extremely prominent in USA?

A

HAV

145
Q

Hepatitis virus related to Norwalk virus, most prevalent in developing countries, FATAL in pregnant women?

A

HEV (ONLY ACUTE)

146
Q

Vaccinations have caused Rapid decline in infections rates of what hepatitis virus worldwide?

A

HAV

147
Q

What is a Dane particle?

A

Enveloped HAV particle

148
Q

What is the Only dsDNA hepatitis virus?

A

HepaDNAvirus–> HBV

149
Q

A patiente infected with HBV will have what in their blood after 1mo?

A

DANE particles
Trillions of 20nm particles and Filaments
HBsAg and phospholipids
NO GENOME

150
Q

What four proteins does the HBV genome encode?

A

Reverse Trasncriptase
HBsAg
HBcAg–> HBeAg

151
Q

What virus markers are seen in an acute HBV infections?

A

HBV DNA
HBsAg
HBc Ab (IgM)

152
Q

Describe the replication process of HBV?

A
Fusion + attachement 
Virus enters nucleus 
**FInished short to make FULL dsDNA
**transcribe DNA-> mRNA 
Make capsid proteins in cytoplasm 
***Reverse Transcriptase== mRNA -> DNA 
Cell buds of ER (no lysis)
153
Q

WHat hepatitis virus is endemic is China and Africa + sexually transmitted?

A

HBV

154
Q

What serological findings are seen in a Resolved HBV infection?

A

Loss of HBV DNA

HBsAg GONE–> HBs Antibodies formed

155
Q

When can a patient be HBsAg negative but HBeAg positive?

A

NEVER

156
Q

What serology is seen in a chronic HBV infection?

A

HBsAg
HBV DNA
EIther HBe Ag (infective) or HBe Antibody (carrier)

157
Q

Hepatitis virus with circular ssRNA genome that requires another virus for infection?

A

HDV –> requires HBV

158
Q

When does HDV cause Severe acute disease vs. HIgh risk of Severe Chronic disease?

A

Co-Infection with HBV= Severe ACUTE

Superinfection == Severe Chronic

159
Q

A patient with chronic HBV infection suddenly has onset of jaundice, fatigue, and malaise?

A

Superinfection with HDV

160
Q

ssRNA+ genome that encodes for 3000+ AA polytprotien that requires NS3 protease for cleavage?

A

HCV

161
Q

What hepatitis infection is associated with DRUG USE, transfusions, and sex?

A

HCV

162
Q

What hepatitis virus is prevalent in 45-55 yo and has a 70% chance of becoming chronic?

A

HCV

**Bouts of acute disease due to several different strains

163
Q

Why can a person have several bouts of HCV infection?

A

Antigenic variation facilitates immune escape

164
Q

Hepatitis virus infecting Sexual partneres, International travelers, AMERICAN INDIANS?

A

HAV

165
Q

Hepatitis affecting Day Care workers, IVDA?

A

HAV

166
Q

Hepatitis affecting IVDA, healthworkers, hemophiliacs?

A

HBV

167
Q

Hepatitis affecting Healthcare, HIV patients, Dialysis, Alcoholics?

A

HCV

168
Q

Which hepatitis viruses are NOT cytolytic?

A

HBV
HCV
**Immune mediated destruction

169
Q

Enterically transmitted Hepatitis viruses with abrupt onset of sharp fever?

A

HAV

HEV

170
Q

parenterally transmitted hepatitis viruses with insidious onset of fever?

A

HBV

HCV

171
Q

Why is HBV chronicity depend on the age of infection? 90% if 5 yo

A

Immune tolerance phase= high HBV DNA, HBeAg +

**Longer is Children because of Lack of strong Innate and CTL immune response to fight of virus)

172
Q

What defines the immune clearance phase of HBV infections? Residual phase?

A

seroconversion from detectable HBeAg-> HBe Antibodies

Residual phase= Loss of HBsAg + DNA

173
Q

What is time line for chronic HCV to become cirrhosis, HCC?

A

Chronic severe== 10years
Cirrhosis== 20 years
HCC== 30 years

174
Q

How is each type of hepatitis virus screened?

A
HAV= ELISA for HAV IgM
HBV= sAg, eAg, eAb, DNA
HCV= cAg, RNA (genotype by serology/RT PCR)
175
Q

What is a definitive form of screening or treatment for HAV?

A

Havarix vaccine–> inactivated

    • vaccinate
  • *>40yo –> Gamma globulin
176
Q

What is a definitive form of screening or treatment for HBV?

A

Screen Blood supplies
Vaccines (Yeast or plasma derived HBsAg)
Alpha 2 interferon, lamivudine, adefovir

177
Q

What is a definitive form of screening or treatment for HCV?

A

Screen blood for HCV RNA

PEG interferon and Ribavarin

178
Q

What is a AE of Ribavarin?

A

Teratogenic

Anemia

179
Q

Which hepatitis viruses are associated with HCC?

A

60% due to HBV

22% due to HCV

180
Q

What Hepatitis vaccine ONLY has 1 serotype and human reservoir?

A

HAV – bases for vaccine

181
Q

Which Hepatitis virus has a revers transcriptase?

A

HBV

182
Q

Which hepatitis viruses are enveloped vs. Non enveloped?

A
Enveloped== B, C, D
Non== A, E
183
Q

What is the route of transmission of HBV?

A

Parenteral–> Blood, semen, vaginal secretions

184
Q

Describe the HBV replication cycle?

A
Entry 
Complete DNA synthesis= FULL ds DNA
Nucleus--> transcribe mRNA
Capsid proteins 
RNA--> DNA
2nd strand synthesis halted early 
Package-> ER--> Release
185
Q

What is different about the symptoms associated with HAV vs HBV?

A

HAV–> symptoms @ 4 wks

HBV–> symptoms @ 8wks

186
Q

What HBV marker is associated with carriers and acutely infected?

A

HBsAg

187
Q

What HBV marker is associated with a person who has HAD the disease or been vaccinated?

A

HBs antibody (IgG)

188
Q

HBV marker that ID those at increased risk of transmission?

A

HBeAg (active marker)

189
Q

HBV marker that ID carriers at LOW risk for transmission?

A

HBe antibody

190
Q

HBV marker that ID person with Past infection?

A

HBc Antibodies (IgG)

191
Q

HBV marker that ID acute or recent infection?

A

Anti-HBc IgM

192
Q

What kind of HBV markers are present in a vacinee?

A

Anti-HBs

193
Q

What kind of HBV markers are present in resolved acute infection?

A

Anti-HBs

Anti-HBc IgM

194
Q

What kind of HBV markers are present in a low risk carrier?

A

HBs Ag
HBV DNA
Anti- HBe

195
Q

What kind of markers are present in a HIGH risk carrier?

A

HBs Ag
HBV DNA
HBe Ag

196
Q

Why do HCV infected individuals have multiple bouts?

A

Reinfection with anther strain

Emergence of quasi-species

197
Q

Which Hepatitis viruses are NOT cytolytic thus cause damage via immune response?

A

HBV

HCV

198
Q

What hepatitis virus has maternal-fetal, sexual, and IVDA transmission routes and is prevalent in SE asia?

A

HBV

199
Q

IVDA associated Hepatitis virus?

A

HCV

200
Q

Sexually active female with Elevated ALT + AST. What is the most likely hep virus?

A

HBV = Sexually transmitted

201
Q

Recent traveler with Increases ALT/AST. Which hep virus?

A

HAV

202
Q

What is the only cause of a AST> 5000?

A

Acetaminophen toxicity

203
Q

What is the clinical picture for Acute hepatitis?

A
Fever 
Fatigue
Abdominal pain 
Enlarged tender liver
High ALT/AST (1000-5000) 
High billirubin (both)
204
Q

Person with HCV infection and ALT/AST > 200 means?

A

Something else is causing Acute liver damage.

HCV never ACUTE

205
Q

Which Hepatitis virus will not have an IgM response?

A

HCV–> NOT ACUTE

**IgM: Anti HEV/HAV/HBcore

206
Q

What does viral DNA or RNA in serum indicate?

A

Active infection but NOT chronic or acute

207
Q

Acute hepatitis patient presents with altered mental status (encephalopathy due to Cerebral edema). What is the Dx & Tx?

A

Fulminant Hepatic failure
Urgent Liver Transplant ONLY
**90% mortality