Vector-borne bacterial infections Flashcards

1
Q

bacilli

A

disease causing bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what kind of bacilli is rickettsia

A

gram-negative

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what makes rickettsia different from other gram negative rods

A
  1. peptidoglycan layer is minimal

2. LPS has weak endotoxin activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what can you not use for treatment in Rickesttsi? and why?

A

Beta-lactams because LPD has weak endotoxin activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

obligate intracellular

A

cannot produce outside of host cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

where does Rickettsia replicate

A

in cytoplasm of cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what stain is used to see Rickettsia

A

Giemsa

Gimenez

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the common name for Rickettsia rickettsii

A

Rocky Mountain Spotted Fever (RMSF)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is the pathogenic factor in Rickettsia rickettsii? how does it work

A

outer membrane protein A (Omp A)

- adherence to endothelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Rickettsia rickettsii replicates where? this results in what

A

cytoplasm and nucleus

-vasculitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

how does Rickettsia rickettsii bypass the immune system

A

intracellular growth protects the bacteria from immune clearance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is the most common Rickettsia causing human disease in USA

A

Rickettsia rickettsii

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

90% of infections occur during what time of year

A

April - September

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is the vector for Rickettsia Rickettsii? what family do they belong to

A

Ticks

Ixodeae family

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

name the 2 forms of ticks that cause Rickettsia Rickettsii

A
Dermacentor andersoni (wood tick)
Dermacentor variablilis (dog tick)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

where is Dermacentor andersoni found

A

rocky mountain states

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

where is dermacentor variablilis found

A

Southeast United states

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what states had the highest incidence rates for Rocky mountain spotted fever

A
Arkansas
Delaware
Missouri
North Carolina
Oklahoma 
Tennessee
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is the reservoir for rickettsia rickettsii

A

ticks via transovarian transmission

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what is the process of a tick biting a human

A
  • bit is painless and goes unnoticed

- after 6-10 hours ….????

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

how long does rocky mountain spotted fever incubate

A

2-14 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what are clinical symptoms for rocky mountain spotted fever

A
fever
chills
headaches
myalgias
abdominal pain 
vomiting
hepatitis
respiratory failure
encephalitis
renal failure 
hypotension
myocarditis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

when does the pathogenic rash appear for rocky mountain spotted fever

A

after 3-5 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

where does the pathogenic rash appear for rocky mountain spotted fever? do all victims get this rash

A

centripetal
palms and soles
no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what does centripetal rash mean

A

spreads from periphery to center

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what happens in 20% of untreated cases for RMSF

A

fatal, clinical suspicion is key

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what will the laboratory findings be for RMSF

A
Thrombocytopenia 
coagulopathy
anemia
normal WBC count
hyponatremia 
Transminitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Transaminitis what does that mean

A

Increased ALT/AST levels

could indicate liver damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

for RMSF when is diagnosis idealistic

A

before the onset of rash is clinical and epidemiological

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

RMSF, the organism in acute phase is detected how in the lab

A
  1. PCR
  2. Immunohistochemical methods in skin biopsy
  3. serology but confirmation needed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

according to the CDC, when is RMSF notified to them

A
fever plus any one of the following 
rash 
eschar
headache
myalgia
anemia 
thrombocytopenia
hepatic transaminase elevation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

how do you confirm RMSF in the lab

A
  1. fourfold change in IgG specific titer reactive with R. rickettsii by indirect immunofluoresense assay (IFA) b/w paired serum specimens ( one speciemen taken in 1st week, second 2-4 weeks later )
  2. detect R. rickettsii DNA in a clinical specimen via amplification of a specific target by PCR asay
  3. demonstrate rickettsial antigen in biopsy or autopsy speciment by IHC
  4. Isolation of R. Rickettsii from clinical specimen in cell culture
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

for laboratory confirmation of RSMF why is IgM not used

A

lacks specificity and are usually false +

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

common name for Rickesstia akari

A

Rickettsailpox

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what is the world distribution for Rickettsia Akari

A

cosmopolitan

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

how is Rickettsia akari transmitted

A

mites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

what is the reservoir for Rickettsia akari

A

rodents ( common house mouse)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

how does R. akari present

A

biphasic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

what happens in the first phase for R. akari

A

1 week after bite: papule to ulcer to eschar at site of bite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

what happens after the first phase of Rickettsialpox

A

incubates for 7-24 days

systemic spread

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

what happens in 2nd phage of R. akari

A
high fever
severe headache
photophobia
papulovesicular rash, 
pox-like progression ( vesicles crust over)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

when does R. Akari 2nd phase heal

A

within 2-3 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

for clinical symptoms with R. akari and R. Rickittsii which one has a milder course

A

R. akari

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Anthrax

A

bacterial disease of sheep and cattle, typically affecting the skin and lungs.
- transmitted to humans, causing severe skin ulceration or a form of pneumonia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

what is the difference in skin rashes with Anthrax and Rickettsialpox

A

anthrax patients only have eschar

Rickettsialpox: papule –> ulcer –> eschar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

If Rickettsialpox is on the differential diagnosis list what other thing should be on the list

A

Anthrax

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

R. Prowazekii has what reservoir

A

humans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

how is R. prowazekii transmitted

A

during blood meal

  • louse defecates highly infective feces
  • introduced into by body by scratching/hand contamination/ injured skin or mucous membrane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

how long can lice feces remain infectious in R. prowazekii

A

100 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

how are louse transfered from human to human in R. prowazekii

A

sharing clothes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

what are 2 syndromes for R. prowazekii

A

acute, potentially severe vasculitis

- Brill-Zinsser disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

when does acute, potentially severe vasculitis occur in R. prowazekii? what other symptoms present

A

7-14 days after contact with infected lice

fever, centrifugal maculopapular rash, CNS symptoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

what is Brill-Zinsser disease

A

recrudescent from 10-50 years after primary infection

- milder form, rash, flu-like symptoms, seen in elderly patients WWII refugees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

how is R. prowazekii tested in the laboratory

A

serology (MIF) test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

when is R. Prowazekii prevelent in the world

A

during disaster, war, famine

rare in US

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

R. prowazekii is transmitted how in the US

A

usually rare in US

  • “flying squirrels”
  • squirrels have fleas, fleas bite humans
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

R. Parkeri common names

A

American Boutonneuse fever

-Tidewater spotted fever

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

where does R. Parkeri usually occur

A

souther United States

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

what is the vector for R. Parkeri

A

Amblyomma maculatum ( Gulf Coast Tick)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

clinical symptoms for R. Parkeri

A

fever, headache, myalgias

eschars and rash on PE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

what is the mortalilty rate for R. parkeri

A

low

62
Q

what lab tests would be used R. Parkeri

A

serology
PCR
culture from skin biopsy

63
Q

what is the treatment for R. Parkeri

A

Doxycycline

64
Q

R. Typhi have what reservoir

A

rodants

65
Q

what is the main vector for R. Typhi

A

Xenopsylla cheopis ( rat flea) also cat flea ( esp in USA)

66
Q

where is R. Typhi usually found

A

worldwide, more in warm, humid areas

67
Q

how are humans infected with R. Typhi

A

inoculation of infective flea feces in bite wounds

68
Q

what is the endemic (murine ) typhus

A

R. typhi

69
Q

what is the epidemic (louse-borne) typhus

A

R. prowazekii

70
Q

what are some clinical manifestations of R. Typhi

A

fever, headache, chills, myalgias
rash ( variable)
mild symtpoms

71
Q

what labs should be runned for R. typhi

A

serology by IFA

72
Q

what is the common name for Orientia tsutsugamushi

A

scrub typhus

73
Q

what is the reservoir for Orientia tsutsugamushi

A

larval mites ( chiggers), via transovarian

74
Q

what is the vector for Orientia tsusugamushi

A

mites, feed only once in a lifetime

75
Q

where is Orientia tsutsugmamushi found in the world

A

Asia Pacific rim

76
Q

clinical symptoms of Orentia Tsutsugamushi

A

severe headache, fever, myalgias
maculopapular rash, spreads CENTRIFUGALLY
CNS complications
heart failure

77
Q

what lab tests check for Orentia Tsutsugamushi

A

Serology (IFA)

78
Q

what is the drug of choice to treat Rickettsial and Orientia infections

A

Doxycylcine

79
Q

what are alternative drugs to treat Rickettsial and Orientia infections

A

Chloramphenical or Fluoroquinolone

80
Q

when should treatment be administered if you think you have Rickettsial or Orientia infections

A

Immediately , don’t wait for confirmatory serology

81
Q

for RMSF what are the rules for giving Doxycline

A

Normally: don’t > 8yrs b/c dental staining/enamal hypoplasia
RMSF: drug of choice regardless of age of patient

82
Q

how should a tick be removed from the skin

A

don’t twist or jerk the tick when pulling with twizzers

83
Q

what are the 5 don’ts for Rickettsial disease

A
  • don’t wait for petechial rash to develop
  • don’t exclude diagnosis because no history of tick bite
  • don’t exclude diagnosis solely for geographic or seasonal reasons
  • don’t withhold therapy if there is any suspicion
  • don’t be afraid to use Doxycyline at any age
84
Q

what type of bacteria are Ehrlichia and Anaplasma

A

obligate intracellulular

85
Q

Ehrlichia and anaplasma don’t have what in the cell memebrane? Therefore what treatment will not work for them

A

no peptidoglycan or LPS

beta-lactams dont work

86
Q

Ehrlichia and Anaplasma grow on what type of cell

A

Hematopoietic cells

87
Q

where do Ehrlichia and Anaplasma replicate

A

phagosomes of host cells

88
Q

what is morula

A

microcolony of Ehrlichiae within a vacuole

89
Q

Another name for Ehrlichia chaffeensis

A

human monocytic ehrlichiosis HME

90
Q

what is another name for anaplasma phagocyophilum

A

human granulocytic anaplasmosis HGA

91
Q

what is the reservoir for Ehrlichia chaffeensis

A

deer and dogs

92
Q

what is the vector for Ehrlichia chaffeensis

A

ticks

Amblyomma americanum

93
Q

where is Ehrlichia chaffeensis usually found

A

southeast

south central and midwest states

94
Q

what and when do clinical symptoms occur for Ehrlichia chaffeenis

A
1-3 weeks after bite: flue-like symptoms
late onset ( 1 week after) rash (spares hands and feet)
95
Q

what lab work is done for Ehrlichia chaffeensis

A

serology by IFA
PCR in blood
- peripheral blood (Giemsa) to see morulae in monocytes is insensitive

96
Q

what is the reservoir for Anaplasma phagocyphilum

A

Deer, sheep, rodents

97
Q

what vector does Anaplasma phagocyphilum use

A

hard-shelled ticks

Lxodes scapularis pacificus

98
Q

where does Anaplasma phagocyphilum predominantly occur

A

Northeast/north-central states and Norther California

99
Q

what are the clinical symptoms for Anaplasma Phagocyphilum

A
1-3 weeks after bite: flue-like symptoms
late onset ( 1 week after) rash (spares hands and feet)
100
Q

what labs are done for Anaplasma Phagocyphilum

A
  • serology by IFA (paired specimens to see increase IgG_
  • blood PCR
  • peripheral blood ( Giesma) to see morulae in granulocytes is insenstive
101
Q

what are laboratory findings for Anaplasma and Ehrlichia

A

leukopenia
lymphopenia
thrombocytopenia
elevated liver enzymes

102
Q

what is the drug choice for Ehrlichia and Anaplasma

A

DOXYCLYCINE REGARDLESS OF AGE

103
Q

what happens if the patient fails to respond to Doxycycline within 3 days

A

there is an infection with other organism

104
Q

Borrelia recurrentis

A

epidemic relapsing fever

105
Q

Borrelia spp

A

endemic relapsing fever

106
Q

Borrelia burgdorferi

A

lyme disease

107
Q

what type of bacteria is Borrelia

A

weakly staining, gram neg. spirochetes

108
Q

what makes Borrelia a different bacteria from the rest of them

A

motile (flagella)

difficult to cultivate

109
Q

what is the leading vector for Borrelia burgdorferi

A

borne disease in USA

110
Q

what 3 main areas are Borrelia burgdorferi found

A

Northeast, Minnesotta, and Wisconsin

111
Q

what are other vectors for borrelia burgdorferi

A

lxodes scapularis

pacificus

112
Q

what is the reservoir for borrelia burgdorferi

A

white-footed mouse (peromyscus leucopus) and white-tailed deer

113
Q

how is borrelia transmitted

A

in tick’s saliva during prolonged period

114
Q

what time of the year does Lyme disease occur

A

June and July

115
Q

what is the incubation period for Lyme disease

A

up to 1 month from tick bite

116
Q

what are the 3 stages of Lyme disease

A

early localized
early disseminated
late disease

117
Q

what happens in early localized

A

distinctive rash: erythema migrans (bull’s eye)

118
Q

what happens in early disseminated

A

multiple EM, facial nerve palsy, meningitis

119
Q

what happens in late disease

A

arthritis (knees) carditis

120
Q

what are symptoms of Lyme disease

A

fatigue, joint pain, cognitive problems

121
Q

for early stage Lyme disease how is diganosis made and why

A

clinically b/c Ig are not detectable within the 1st 4weeks of infection

122
Q

what laboratory items would you use for Lyme disease

A

EIA or FIA

confirmatory Western Blot

123
Q

what is used to treat Lyme disease

A

Amoxicillin or cefuroxime for children equal to 8 years

124
Q

what is used to treat the CNS, carditis or recurrent arthritis in lyme disease

A

Ceftriaxone

125
Q

what does STARI stand for

A

Southern Tick-associated rash illness

126
Q

what are clinical symptoms for STARI

A

rash typical of erythema migrans and mild flu-like symptoms in NON-LYME ENDEMIC AREAS

127
Q

STARI is associated with a bite by what

A

Lone Start tick ( A. americanum)

128
Q

Preliminary studies show the cause of STARI is postulated to be a

A

spirochete: B. lonestari

129
Q

where does STARI occur

A
Missouri
Maryland
Georgia
South Carolina
North Carolina
130
Q

what may serve as a reservoir for STARI

A

white-tailed deer

131
Q

name 4 reasons why STARI is different from lyme

A

onset of lesion was shorter

  • less likely to have multiple skin lesions, smaller sized lesions
  • rapid recovery
  • not linked to arthritis, neurologic disease, or chronic symptoms
132
Q

what medicine is used to treat STARI

A

Doxycycline

Amoxicillin

133
Q

under what circumstance does B. recurrentis occur

A

natural disasters

unsanitary conditions

134
Q

what is reservoir for Borrelia spp.

A

rodents, small mammals

135
Q

how do ticks transmit Borrelia spp.

A

feed nocturnally and contaminate the wound with saliva and feces that are infectious

136
Q

what are clinical syndromes for relapsing fever

A

fever, chills, headaches, hepatosplenomegaly

137
Q

what is the timeline for relapsing fever clinical symtpoms

A

incubation 1 week
afebrile period of 1 week
return symptoms
relapse

138
Q

what is the mortality rate for relapsing fever

A

high 40%

139
Q

how does one lab diagnose relapsing fever

A

Giemsa on peripheral blood during febrile episode

140
Q

what is the treatment of relapsing fever

A

Doxycycline

Penicillin and Erythromycin for pregnant and children under 8 years of age

141
Q

what is Babesia

A

protozoa

142
Q

Babesia shares the same vector and reservior as what other disease

A

B. burgdorferi

143
Q

what is the vector and reservoir for Babesia

A

v: lxodes ticks
r: white footed mouse

144
Q

what is the most common species for Babesia

A

babesia microti

145
Q

Babesia is what kind of parasite and what does it mimic

A

INTRA-ERYTHROCYTIC PARASITE

MALARIA

146
Q

what is the life cycle of Babesia

A

blood meal, introduces sporozoites into human host

  • sporozoites enter erythrocytes, asexual replication
  • replication causes the disease
147
Q

what are clinical manifestation for Bebsia

A
hemolytic anemia
influenza like symptoms ( fever, chills, body aches)
Splenomegaly
hepatomegaly
jaundice
148
Q

what are risk factors for Babesia

A

advanced age, immunocompromised person

149
Q

how is Babesia lab diagnosed

A
  • detected by microscope examination of blood smear (maltese cross)
  • double check, b/c hard to distinguish from plasmodium
  • PCR detects low levels of parasites
150
Q

why is serology not helpful for Babesia

A

cannot distinguish between acute versus old infection

151
Q

what is the treatment for babesiosis

A

combination therapy
mild disease: Atovaquone PLUS azithromycin
severe disease: Clindamycin PLUS quinine