Chap8- General Principles Flashcards Preview

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Flashcards in Chap8- General Principles Deck (192):
1

What is a prion

abnormally folded host protein PrP

2

What diseases are caused by prions

kuru- spongiform encephalopathie
Creutzfeldt-Jakob disease
Bovine spongiform encephalopathy (mad cow)
variant CJD- from infected bovine

3

How do prions cause disease

undergo a conformational change that is resistant to proteases
the resitance PrP then convert normal PrPs

4

how can CJD be transmitted

iatrogenically, surgery, organ transplant, blood transfusion

5

What is a virus

obligate intracell organism that need host machinery
have genome in a capsid and sometimes encased in lipid membrane

6

Under a light microscope how can you identify a virsu

inclusion bodies

7

What are the common viruses with inclusion bodies

cytomegalovirus
herpes
smallpox and rabies

8

what is a latent infection

nonreplicating form of a virus

9

What are bacteria

prokaryotes, do not have membrane bound organelles
gram + have single outside layer
gram - have 2 thin lipid bilayers

10

what are pili on bacteria used for

attach to host cells or ECM

11

Describe staining of Staph aureus

gram + cocci in clusters- degenerating neutrophils

12

describe staining of Strep. pneumoniae

gram + elongated cocci in pairs and short chains

13

describe staining of clostridia species

gram + and -
although tru gram +

14

What are common gram - rod bacteria

E coli, klebsiella pneumoniae

15

What is the most common seem gram - diplococci

neisseria gonorrhea

16

What bacteria causes lyme disease meningoencephalitis

spirochete Borrelia burgdorferi

17

What bacterium contributes to dental plaque

strep mutans

18

what are facultative intracellular bacteria

can survive and replicate outside or inside host

19

what are obligate intracellular bacteria

need the host to survive

20

are chlamydia and Ricketssia, obligate or facultative

obligate because rely on ATP for energy source

21

What is the most frequent infection that leads to female sterility

chlamydia trachomatis
scarring fallopian tubes and blindness via conjunctivitis

22

How does Ricketssia cause damage

injures endothelial cells and causes hemorrhagic vasculitis and sometimes CNS

23

Rocky Mountain spotted fever and epidemic typhus are examples of what

Ricketssia family

24

What bacteria are the tiniest free living organisms known

mycoplasma organisms

25

What are fungi

eukaryotes with thick, chitin cell walls with ergosterol-containing membranes

26

What are the 2 shapes of fungi

rounded yeast cells or slender filamentous hyphae

27

describe the types of hyphae fungi charactersitics

septate(with cell walls) or aseptate

28

Describe fungi thermal dimorphism

hyphal forms at room temp then yeast at body temp

29

What are conidia

asexual spores from fungi

30

Describe the superficial fungi

dematophytes that are referred to as tinea

31

what are examples of fungal species that invade subcut

sporothrichosis
tropical mycoses

32

Describe the clinical features of oportunistic infections in immunocompromised patients

tissue necrosis, hemorrhage and vascular occlusion

33

What opportunistic infection is seen in AIDS patients

Pneumocystis jiroveci

34

What are protozoa

single celled mobile eukaryotes

35

What is the protozoa in RBC? in Macrophages?

RBC plasmodium
macrophages leishmania

36

What are the most common intestinal protozoans?
What are their 2 forms

entamoeba histolytica
giardia lamblia
motile trophozoites that attach to intestinal epithelial wall
immobile cysts that are R to stomach acids and infectious when ingested

37

What type of organism is trichomonas vaginalis

protozoa

38

How are the blood borne protozoans trasnmitted

insect vectors

39

How is toxoplasma gondii acquired

contact with oocyst shedding kittens or by eating cyst-ridden undercooked meat

40

What are helminthes

highly differentiated multicellular organisms with complex life cycles

41

What are the differences of ascaris, toxocara and echinococcus species of helminthes

ascaris lumbricoides is adult
toxocara canis is immature
echinococcus species are asexual larval forms

42

is 10 hookworms a problem

rarely but 100 can cause anemia

43

What is the mode of disease caused by schistsomiasis

disease is from inflammatory response to eggs or larvae rather than to the adults

44

What are ectoparasites

insects: lice, bedbugs, fleas or arachnids: mites, ticks and spiders

45

What is typically found at the site of a ectoparasite bite

lymphocytes, macrophages, eosinphils

46

What bacteria can be seen in H&E stains

the inclusion body forming bacteria, Cadida and mucor fungi, most protozoans and all helminthes

47

Where are organisms best visualized

edge of a lesion not the center

48

Acid Fast staining is used to visualize what

mycobacteria and nocardiae

49

silver stains are used to visualize what

fungi, legionella and penumocystis

50

periodic acid shiff is used to visualize what

fungi and amebae

51

mucicarmine stain is used to visualize what

cryptococcie

52

giemsa stain is used to visualize what

campylobacteria and leishmaniae, malaria parasites

53

What marker is used Dx shortly after onset symptoms

IgM Ab

54

What rise in titer is considered Dx

4X

55

what is used for Dx of gonorrhea and chlamydia, TB and herpes encephalitis

PCR

56

in detecting herpes is a PCR of CSF more sensitive or a viral culture of CSF

the PCR

57

For chalmydia do you want normal culture or necleic acid tests as well

nucleic acid detects 10-30% more

58

What does ebola virus cause

epidemic ebola hemorrhagic feer

59

what does hantaan virus cause

hemorrhagic fever with renal syndrome

60

what does campylobacter jejuni cause

enteritis

61

what does HTLV-1 cause

T cell lymphoma or leukemia, HTLV- assoc myelopathy

62

What does S.aureus cause

Toxic shock syndrome

63

what does E coli cause

hemorrhagic colitis, hemolytic-uremic syndrome

64

What does Borrrelia burgdorferi cause

lyme disease

65

What does helicobacter pylori cause

gastric ulcers

66

what does Hep E cause

enterically transmitted hepatitis

67

what does Hep C cause

Hep C

68

When was vibrio cholerae detected

1992 as new choler straing

69

what causes cat scratch disease

bartonella henselae

70

what is kaposi sarcoma assoc with

AIDs patients HHV-8

71

When was west nile virus identified

1999

72

When was SARS identified and what is its manifestation

2003
coronavirus causing severe acute respiratory syndrome

73

What species have acquired antibiotic resistance

Mycobacterium tuberculosis, Neisseria gonorrhoeae, S.aureus, Enterococcus faecium

74

What are catergory A bioterism organisms

Anthrax- bacillus anthracis
Botulism- Clostridium botulinum toxin
Plague- yersinia pestis
smallpox- variolla major virus
tularemia
viral hemorrhagic fevers

75

What are catergory B bioterism organisms

Brucellosis, epsilon toxin-Clos perfringens
food safety(salmoneela, e coli)
glanders
meliodosis
staph enterotoxin B
Ricin toxin (castor beans)
typhus fever
viral encephalitis

76

What are category C bioterism organisms

emerging infectious disease threats such as Nipah and Hantavirus

77

What is common in the cat A bioterism organisms

need small dosages to cause large infection
aerosolize

78

What are signs of smallpox infection

7-17 days have high fever, HA and backache
then rash on mouth and pharynx, face and forearms that continues to spread

79

What components of skin are part of our immunity

dense keratinized outer layer with pH 5.5 and the FA inhibit microorganism growth

80

What organism can enter unbroken skin and how

Schistosoma larvae from freshwater snails via collagenase and elastases

81

What are the GI defenses against microorganisms

acidic gastric secretions
layer of viscous mucus
pancreatic enzymes and bile dtergents
mucosal defensins
flora
secreted IgA Ab

82

why are shigella and giardia cysts so relentless on the GI track

resistant to gastric acid

83

What make the IgA Ab in GI

MALT mucous associated lymphoid tissues covered by M cells that transport the Ag

84

What weakens our GI system

low gastric acidity by Ab that alter normal flora
Resistant nonenveloped viruses

85

how do staphylococcal strains cause GI disease without bacterial multiplication

powerful enterotoxins on the food

86

What is the mech of V cholerae and E coli in the GI

release exotoxins that cause gut to secrete large volumes of fluid

87

what is the mech of shigella, salmonella and campylobacter in the gut

invade and damage intestinal mucosa and lamina propria causing ulceration, inflammation and hermorrhage

88

What is the mech of salmonella typhi in GI

enters through peyer patches and mesenteric lymph into blood stream resulting in systemic infection

89

What tapeworm clinically apppears to cause pernicious anemia

Diphyllobothrium datum from depleting host of B12

90

How do respiratory pathogens escape innate mech

attach to epithelial cells in lower respiratory tract and pharynx
or impair ciliary activity

91

qHow do influenza viruses attack respiratory system

have hemagglutinin proteins that project from surface protein and then neuroaminidase which cleave it and allow rvirus to enter host cell

92

what pathogens inhibit ciliary mech of airways

haemophilus influenza and Bordetella pertussis

93

what lung infections are chemotherapy patients most at risk for

Aspergillus species

94

Why are women more prone to urinary infections

shorter urethra

95

what happens if UTI retrograde to the bladder

can go further anc cause chronic polynephritis

96

what is the initial microbial spread

tissue planes of least resistance and sites drained by lymph

97

What pathogens can leukocytes carry

herpes, HIV, mycobacteria and leishmania and toxoplasma

98

What pathogens are carried on RBC

viruses- colorado tick fever virus
parasites- plasmodium and babesia

99

what are the manifestations os serious pathogenic insult

fever, low BP, sepsis

100

poliovirus enters via intestine but spread where

kills motor neurons

101

shistosoma mansoni parasites penetrate skin but damage ehere

localize in blood and mesentery damaging liver and intestine

102

Where does varicella zoster virus hide latently until activated

in the DRG then on activation travels on nerves to cause shingles

103

when can there be transmission of treponemas in utero

late second trimester and causes severe fetal osetochondritis and periostitis

104

What infections can occur through maternal milk

CMV, HBV, Human T cell leukemia virus 1

105

What pathogens are usually spread via respiration

viruses and bacteria

106

what pathogens are spread fecal-orally

viruses helminths

107

What are some water-borne viruses

Hep A and E
poliovirus
rotavirus

108

what pathogens are spread mainly through saliva

EBV, CMV, mumps

109

what pathogens are spread by sexual transmission

viruses: HPV, HSV, HBV, HIV,
bacteria: T. pallidum, N. gonorrhoeae, C.trachomatis
fungi: Candida
protozoa: Trichomonas
Arthropods: Phthirus pubis (crabs)

110

animal to human transmission is called what

zoonotic infections

111

What does chlamydia cause in a male? female? both?

urethritis, epididymitis, proctisis
female: urethral syndrome, cervicitis, salpingitis
both: lymphogranuloma venerum

112

What infections causes ectopic pregnancies in women

Neisseria gonorrhoeae

113

Are viruses or bacterial infections more harmful to a fetus

viruses

114

What are nosocomial infections

infections acquired at the hospital

115

what is the most common cause of hospital acquired infections

hands of healthcare workers

116

What is the main innate immune cell

NK

117

what pathogens are known to stay latent until immune system is down

EBV and TB

118

what are the mech in which microorganisms cause disease

contact or enter host and directly cause cell death
release toxins and kill cells or enzymes that slowly degrade
induce host immune responses causing additional damage

119

What is the definition of tropism

predilection fo viruses to infect certain cells

120

what are the factors for tropism

-expression of host cell R for the virus
-presence of cell transcription factors that recognize viral enhancer and promoter sequences
-anatomic barriers
- local temp, pH and host defenses

121

What does HIV use to enter host

its glycoprotein gp120 binds CD4 T cells via CXCR4 and CCR5

122

How does EBV get into cells

its envelop eglycoprotein gp350 cinds complement R 2 (CR2/CD21) on B cells

123

Why do rhinoviruses infect upper respiratory tract only

replicate optimally at lower temp in URtract

124

What are the direct cytopathic effects of viruses

some viruses kill cells by preventing synthesis of host macromolecules(DNA RNA) by enzymes and toxic proteins or inducing apoptosis

125

What is the primary cell defense for viruses

CTLs

126

Bacterial damage to host depends on what

ability to adhere and enter/invade or deliver toxins

127

what is the role of plasmids and bacteriophages in infections

can pass virulent elements into other cells
like codes for Ab-resistance

128

what are the two main types of Ab-R bacteria

vancomycin R enterococci and methicillin-R staphylococci

129

What is quorum sensing

how many bacteria can coordinate and regulate gene expression in large populations

130

How does S. aureus specifically coordinate virulence factors

secrete autoinducer peptides stimulating toxin production

131

What are biofilms

a viscouse layer of extracell polysaccharides that adhere to host and make bacteria inaccessible to immune effector mechanisms increasing their Resistance

132

What type of infections are biofilms characteristic of

bacterial endocarditis, artificial joint infections, respiratory infections in CF patients

133

What are Adhesins

bacterial surface molecules that bind host or ECM

134

What bacteria utilizes protein F and teichoic acid to bind to fibronectin

Step pyogenes( gram +)

135

What is on the strains of E colie that cause UTIs

specific P pills which binds to val(1a4) on uroepithelial cells

136

What is the main mech in which N. gonorrhoeae evades immune system

type of pili expression

137

How do bacteria enter host cells

using host immune response like coating bacteria with C3b

138

Once coated by C3b what does mycobacterium TB do

binds CR3 on macrophages and is endocytosed then blocks fusion of phagosome wtih lysosome

139

How does listeria monocytogenes spread

manipulate cell cytoskeleton
forms pore forming protein to evade macrophage degradation

140

What are endotoxins? exotoxins?

endotoxins are components of bacterial cell
exotoxins are secreted by bacteria

141

What is used Dx serotologically to differentiate bacteria

detection O antigen found on gram -

142

What is the response to LPS

induces cytokines and chemokines of the immune system to enhance T lymph activation
but high levels thought to have role in septic shock b/c induce TNF IL1 IL12

143

What R does LPS bind to

TLR4

144

what are types of exotoxins

enzymes, toxins that alter intracell signaling, neurotoxins, SuperAg

145

What bacteria produce A-B toxins

bacillus anthracis. V.cholerae and some strains E.coli

146

What bacteria produce neurtoxins

clostriudum botulinum and clostridium tetanii

147

How do superAg cause massive T cell activation

bind conservative portions of T cell R

148

What bacteria produce Super Ag associ with TSS

S aureus and S pyogenes

149

how can s pyogenes lead to glomerulonephritis

Ab bind Ag and form IC that deposit in the renal glomeruli

150

What is the association with pathogens and cancer

usually involve chronic inflammation

151

how do microbes evade the immune system

growth in niches that are inaccessible to host immune system
antigenic variation
R to innate immune defenses
impairment of effective T cell repsonses

152

What pathogens replicate in sites that are inaccessible to host immune

C. difficile
S typhi in gall bladder

153

how does malaria sporozoites evade immune

enter liver cells so quickly before immune response is effective

154

What are the main mech which microbes express Ag to evade immune system

low dfidelity of viral RNA polymerases and reassortment of viral genomes create viral antigenic variation

155

What is different between serotypes of S pneumoniae

different capsular polysaccharides expressed

156

What viruses have high mutation rates

HIV and influenza

157

What viruses can undergoe genetic reassortment

influenza and rotavirus

158

what bacteria undergo genetic rearrangement

Borrelia burgdorgeri
N gonorrhoeae
Trypanosoma sp (african sleeping sickness)
Plasmodium sp. (malaria)

159

what viruses/bacteria have large diversity of serotypes

Rhinoviruses
strep pneumoniae (meningitis)

160

what are our initial defense mech on invading microbes

defensins, cathelicidins, thrombocidins

161

How does E coli cause meningitis in newborns

sialic acid which won't bind C3b so evades alternative C' pathway

162

how does salmonella reduce TLR activation

modifies LPS

163

What bacteria secrete proteases that degrade Ab

Neisseria, haemophilus and streptococcus

164

what pathogens multiply in phagocytes

bacteria: mycobacteria, listeria and legionella
fungi: cryptococcus, neoformans
protozoa: leishmania, trypanosomes, toxoplasmas

165

what viruses produce prteins that block C'

herpes and poxviruses

166

What pathway is largely inhibited by viruses

IFN JAK/STAT

167

How do microbes affect the MHC molecules

can alter them to change peptide presentation or even inhibit the NK or T cells

168

Herpes virus affects which MHC molecules

both

169

EBV effects what immune cell

B cells

170

TIV effects what immune cells

T cells, macrophages and dendritic

171

What are patients with Ab deficiency like X linked agammaglobulinemia prone to

S pneumoniae, H influenzae and S aureus
and viral rotavirus and enteroviruses

172

Patients with t cell defects are prone to what

intracell pathogens like viruses and some parasites

173

patients with C' defects are susceptible to what

S penumoniae. H influenzae and N meningitidis

174

deficiencies in Neutrophils leads to what

increased s aureus infections and gram - bacteria

175

What are patients who receive bone marrow transplant at higher risk for

aspergillus and pseudomonas species infections

176

Patients with CF are prone to what infections

P aeruginosa
S aureus
Burkholdaria cepacia

177

What are patients with sickle cell anemia prone to

encapsulated bacteria like S pneumoniae

178

Burn victims are prone to what infection

P aeruginosa

179

What is the difference of M. TB in normal patient vs AIDS

usually causes well formed granulomas with few mycobacteria present
in AIDS causes multiple profulsey macrophages which fail to coalesce into granulomas

180

What are the 5 major patterns of tissue reaction to infection

Suppurative-Purulent infection
mononuclear/granulomatous
Cytopathic/cytoproliferative
Tissue necrosis
Chronic inflammation/scarring

181

What is suppurative infection characterized by

increased vasc permeability and leukocytic infiltration, predominately neutrophils
release of pus

182

What are the common pyogenic bacteria

gram + cocci
gram - rods

183

What is pus formed from

neutrophils and liquefactive necrosis

184

what is the difference of pneumococci and staphylococci in lungs

pneumo causes lobar pneumonia sparing the walls
staphylococci destroyes the walls and form abscesses that heal with scar formation

185

acute mononuclear inflammation is usually in response to what

viruses

186

what cell predominates in syphilis infection?
HBV?

syphilis is plasma cells
HBV is lymphocytes

187

Granulomatous inflammation is distinctive of what type of infection? give examples

infectious agents that resist eradication and stimulate strong T cell mediated immunity
M.tb, Histoplasma capsulatum, schistosome eggs

188

What type of necrosis typically happens in granulomatous inflammation

caseous

189

What is the characterization of cytopathic-cytoproliferative reactions and what class of pathogens cause it

cell necrosis or proliferation usually with few inflammatory cells
viruses

190

what are polykaryons and what viruses cause this

fusion of cells
measles and herpes virus

191

C. perfringes causes what type of necrosis

gangrenous due to release of toxic material

192

what causes "pipe stem" fibrosis of the liver or bladder wll

schistosomal eggs