Soft Tissue Infections II: Bacterial and Fungi - Kozel Flashcards
1
Q
Bacillus is aerobic or anaerobic?
A
aerobic and a facultative anaerobe
2
Q
The bacillus capsule has a poly-gamma-D-(blank) chain
A
glutamic
3
Q
the bacillus capsules aids in (blank)
A
antiphagocytic properties
4
Q
T/F: the bacillus capsule induces protective immunity
A
true
5
Q
The bacillus anthracis toxin is similar to the (blank) toxin of cholera
A
AB
6
Q
What are the three toxins of anthracis
A
Protective ag
Lethal factor
Edema factor
7
Q
What is the role of protective ag?
A
binds cellular receptors to aid in the uptake of LF or EF.
8
Q
What is the function of lethal factor?
A
it is a protease that induces cell death
9
Q
what is the function of edema factor?
A
works on adenylate cyclase and produces edeam
10
Q
What type of anthrax follows innoculation with spores?
A
cutaneous anthrax
11
Q
what type of anthrax begins as a painless papule that forms a black eschar formation?
A
cutaneous
12
Q
What type of anthrax follows ingestion of spores and may spread to systemic disease?
A
GI anthrax
13
Q
Describe the spread of inhalation anthrax?
A
lungs to lymph nodes to systemic
14
Q
Hypotension, pulmonary edema, massive bacteremia, and acute fatal toxic shock are symptoms of what type of anthrax?
A
inhalational anthrax
15
Q
T/F: inhalational anthrax has a short incubational period
A
false; may be prolonged
16
Q
T/F: inhalational anthrax is fatal if untreated
A
true
17
Q
What are the two sample sources for anthrax?
A
blood or material from the eschar
18
Q
The gram stain of anthrax blood is often (pos/neg)
A
positive
19
Q
What kind of stain do you need to do to see the anthrax capsule?
A
negative stain
20
Q
What is the role of the laboratory response network?
A
Federal national organization of labs across the country that can employ BSL-3 techniques if necessary to rule out bioterrorist agents; usually do PCR of the samples.
21
Q
antrhax is a disease of (carnivores/herbivores)
A
herbivores
22
Q
T/F: anthrax is communicable
A
FALSE
23
Q
What bug causes woolsorter’s disease?
A
anthrax
24
Q
What type of vaccine is the human vaccine for anthrax?
A
AVA: acellular vaccine adsorbed
25
What type of anthrax vaccine is given to animals?
live vaccine
26
T/F: there is a point of no return during anthrax exposure due to massive toxin production
true
27
What is the abx of choice to treat anthrax?
ciprofloxacin
28
What is the prophylaxis given to people exposed to anthrax?
AVA vaccine and ciprofloxacin or doxycycline for 40 days
29
What is the gram stain on clostridium?
gram pos
30
is clostridium aerobic or anaerobic?
anaerobic
31
T/F: clostridium can form spores
true
32
Where do you find clostridium?
ubiquitous in soil, water, and sewage
33
T/F: clostridium is part of the normal flora of the gI tract of man and some animals
true
34
T/F: clostridium doesn't produce toxins
false; makes many
35
What is the major lethal toxin of gas gangrene?
alpha toxin
36
clostridium alpha toxin has (blank)ase activity and can lyse many cells leading to massive hemolysis
lecithinase
37
(blank) toxin is released by clostridium when the cells undergo sporulation
enterotoxin
38
What is the function of clostridium enterotoxin?
altered membrane permeability leading to loss of fluid and ions
39
T/F: clostridium enterotoxin is a Superag
true
40
How do you get myonecrosis?
introduction of spores or vegetative cells by trauma or surgery
41
Clostridium food poisoning follows eating contaminated what?
meat
42
necrotizing enteritis is caused by the combo of what two foods?
clostridium contaminated pork and sweet potatoes
43
What causes death in necrotizing enteritis?
necrotizing destruction of jejunum
44
What toxin causes necrotizing enteritis?
beta toxin
45
When dealing with clostridium food poisoning, what two things must you distinguish?
colonization from infection
46
How do you test for clostridium in food poisoning?
enterotoxin immunoassay from stool
47
What is the mortality in soft tissue infections with clostridium?
40-100%
48
What are all of the tx for clostridium soft tissue infection?
Surgical debridement
High does PCN and clindamycin
Wound care
49
T/F: abx are not effective in clostridium food poisoning
true
50
what shape is borrelia?
spirochete
51
T/F: borrelia can be grown in culture
true
52
What is the incubation period of borrelia?
3-30 days
53
80% of pts show what type of rash after getting borrelia?
erythema migrans
54
How long is it until initial lyme disease goes to early disseminated disease?
days to weeks after onset of the rash
55
the early disseminated stage of lyme disease is noted by multiple (blank) skin lesions
annular
56
What are the complications of early disseminated lyme disease?
fatigue, arthritis, myalgia, cardiac dysfunction, and neurologic symptoms
57
How long does it take to progress to a late infection of lyme disease?
months after initial presentation
58
Where in the world do we see more chronic skin involvement in late lyme disease?
europe
59
Post-lyme disease syndrome has symptoms similar to (blank)
chronic fatigue syndrome and fibromyalgia
60
T/F: most patients with chronic lyme disease actually don't remember having bulls eye skin lesions
TRUE
61
What is Acrodermatitis chronica atrophicans?
chronic blueish red skin lesions seen in late disseminated Lyme disease, seen commonly in Europe
62
what are the two ways to Dx lyme disease?
erythema migrans or one late manifestation (MSK, CNS, or cardio) plus lab confirmation
63
T/F: gram staining is the first step in lab Dx of lyme disease
FALSE; direct microscopy not useful
64
Can you culture lyme disease in agar?
nooooope
65
What is the preferred lab test to dx lyme disease?
Ab testing
66
Describe the tree of Ab testing for lyme disease?
1. low levels of Ab early in infection
2. ELISA followed by a western
3. IgM peaks after 6-8 weeks
4. IgG peaks 4-6 months and persists
67
What type of hard tick is the vector for lyme disease?
Ixodes
68
What life cycle stage of the hard shelled tick causes lyme disease?
nymph stage in greater than 90 percent of the cases
69
What is the reservoir host for the larval form of lyme disease?
white footed mouse
70
what is the reservoir host for the adult form of lyme disease?
white tailed deer
71
When in the year is the lyme disease most common?
may-september when the ticks are in nymph stage
72
What are the regional foci for lyme disase within the US?
Northease and mid-atlantic, upper midwest and pacific midwest
73
What is the drug of choice in early lyme disease?
doxycycline; amoxicillin, cefuroxime, or erythromycin are alternatives
74
Recurrent arthritis or central or peripheral nervous system disease in lyme disease is treated with what?
IV cetriaxone; alternatives include cefotaxime or doxy
75
Can you use abx to treat post-lyme disease syndrome?
nope, just Tx symptomatically
76
Rickettsia are intracellular parasites that only grow in the cytoplasm of (blank) cells
eurkaryotic
77
T/F: ricekttsia is maintained and transmitted by arthropods
true
78
T/F: humans are accidental hosts of rickettsia
true
79
Where in the cell does rickettsia replicate?
cytosol and nucleus
80
RMSF results in (blank) caused by endothelial cell damage and leakage of the blood vessels
vasculitis
81
What is the incubation period for RMSF?
7 days
82
If you hear of a centripetal rash that turns spotted, what do you think?
RMSF
83
T/F: death may occur within a week of symptom onset of RMSF
true
84
What are the complications of RMSF?
CNS, renal, or cardiac problems
85
Can you diagnose RMSF in the in house lab?
nope, need to send it out to a reference lab
86
What is the method used to Dx RMSF?
immunofluorescence staining
87
How is RMSF cultured?
in tissue or embryonated eggs
88
The Weil-Felix test is used to detect Abs that cross react with the (blank) ag, but is no longer recommended for RMSF for a lack of sensitivity and specificity
Proteus Ag
89
Indirect immunofluorescence of RMSF detects (blank) shed across rickettsial species
LPS
90
What is the principal reservoir and vector of RMSF?
ticks
91
When in the year do most RMSF infections happen?
April - September
92
What is the drug of choice for RMSF? Alternatives?
Doxy is choice, no alternatives
93
T/F: empiric doxycycline should be started if RMSF is suspsected
true; need early treatment for survival
94
which rickettsia is transmitted by mites/chiggers and has a resrvoir in wild rodents? where is this one found?
Orientia tsutsugamushi; found in Japan, eastern Asia, N. Australia; aka scrub typhus
95
what is epidemic typhus?
Rickettsia prowazekii
96
What is the geographic distribution of rickettsia prowazekii?
worldwide
97
What is the reservoir for epidemic typhus? the vector?
reservoir: human
vector: human body louse
98
What causes murine endemic typhus?
rickettsia typhi
99
What is the geographic distribution of endemic typhus?
worldwide
100
What type of rickettsia has a GRADUAL onset?
endemic typhus
101
What is unique about Y pestis staining?
BIPOLAR staining
102
Y pestis is gram what?
negative
103
T/F; Y pestis is an enterobacteriae
true
104
What type of plague follows flea bites?
bubonic plague
105
what is a bubo?
painful, swollen lymph node
106
what is the mortality of bubonic plague if untreated?
75%
107
from what symptom does "black death" get its name?
black plague gangrene
108
What type of plague is this?
Initially, headache, malaise and pulmonary signs
Highly infectious; rapidly fatal if untreated
pneumonic plague
109
T/F: Y pestis readily diagnosed by automated systems because of its danger as a biothreat
false; often misdiagnosed by machine
110
What are the natural hosts of plague?
rats, squirrels, rabbits
111
What form of plague is spread from person to person?
pneumonic
112
What is the firstline drug and the alternative treatment for plague?
1. streptomycin
| 2. doxy
113
(blank) are molds that invade stratum corneum of skin or other keratinized tissues
dermatophytes
114
Trichophyton, Microsporum, and Epidermophyton are the major genera of (blank)
dermatophytes
115
What is athlete's foot?
tinea pedis
116
What organisms often cause athelte's foot?
T. rubrum, T. interdigitale, sometimes E. floccosum
117
what is jock itch?
tinea cruris
118
what is the most common jock itch infection?
T. rubrum
119
The differential diagnosis of Tinea corporis includes:
eczema and psoriasis
120
what are the most common causes of tinea corporis?
T. rubrum, M. canis, M. gypseum
121
The fuck is scalp ringworm?
Tinea capitis; causes scaling of scalp, itching, and hair loss
122
T/F: there is only one organism that causes scalp ringworm
FALSE, many species of trichophyton and microsporum
123
What is Onchomycosis?
infx of the nails
124
What speceis causes onhcomycosis?
many from trychophyton and microsporum
125
Anthropophilic, zoophilic, and geophilic species belong to the class of (blank)
dermatophytes
126
(Anthropophilic/Zoophilic) infx are chronic and relatively noninflammatory but are hard to cure while (Anthropophilic/Zoophilic) produce a profound host reaction and highly inflammatory lesions but are easily treatable
Anthropophilic: nbd
Zoophilic: holy shit that's bad
127
How do you diagnose dermatophytes?
Direct exam of scrapings or clipppings; set in KOH for microscopy
128
How long does it take and what type of medium is needed to culture dermatophytes?
mycologic culture, need 7-28 days
129
What are the two drugs of choice for dermatophytes?
azoles or terbinafine
130
When do you use oral agents for dermatophyte infx?
for more extensive infections of hair and nails; use itraconazole, fluconazole, terbinafine, griseofulvin
GIFT
131
Pityriasis is aka
tinea versicolor
132
What does tinea versicolor do?
makes you white if you are dark and makes you dark if you are white
133
If you take a look under the scope of a sample of tinea versicolor, what do you see?
budding yeast like cells
134
"Spaghetti and meatballs" KOH appearance is indicative of what?
tinea versicolor
135
T/F: tinea versicolor is found worldwide
true
136
Where is tinea versicolor the most prevalent?
tropical or subtropical, up to 60%; makes sense; you get it at the beach normally
137
T/F: tinea versicolor can be spread from person to person
treu
138
WHat are the two treatments for tinea versicolor?
topical azoles or selenium sulfide shampoo or oral azoles for systemic issues
139
what causes Lymphocutaneous sporotrichosis?
Sporothrix schenckii
140
Sporothrix schenckii has what appearance?
dimorphic fungus
141
How do you get Lymphocutaneous sporotrichosis?
traumatic innoculuation of soil or vegetable matter
142
What is the common name for Lymphocutaneous sporotrichosis?
rose gardener's disease
143
t/F: the site of innoculation of Lymphocutaneous sporotrichosis may ulcerate
ture
144
Where do secondary nodules appear in Lymphocutaneous sporotrichosis?
along the same lymphatic chain that drains the first nodule
145
T/F: Lymphocutaneous sporotrichosis is only found in eastern europe
false; world wide
146
If you see budding yeast at 35C and mold at 25C when culturing from the pus of a nodule, what do you have?
Lymphocutaneous sporotrichosis; DIMORPHIC fungus
147
what is the Tx for Lymphocutaneous sporotrichosis?
itraconazole
148
What disease is this>?
Localized, chronic, granulomatous process involving cutaneous and subcutaneous tissues
Multiple granulomas and abscesses containing masses of hyphae
Abscesses drain through skin; may extrude granules of hyphae
May destroy muscle and bone locally
Mycetoma, caused by Curvularia, Fusarium, Exophiala
149
What specific thing must you see under the scope to Dx mycetoma?
grains or granules in the exudate
150
Where is mycetoma most common?
tropical areas with LITTLE rainfall
151
What is the only definitive Tx for mycetoma?
amputation!!
152
What type of sample must you collect to Dx bacillus anthracis?
blood or material from eschar; do direct exam with scope and gram stain
153
What type of sample must you collect to Dx clostridium perfringens?
fluids from the site of lesions; direct exam with scope and gram stain; culture and look for rapid anaerobic growth on blood agar
154
What type of sample must you collect to Dx borrelia burgdorferi?
either erythema migrans ~5cm or at least one systemic symtptom PLUS lab Dx:
IgM in 6-8 weeks or
IgG 4-6 months
155
What type of sample must you collect to Dx RMSF?
send out to a reference lab!! Detects LPS
156
What type of sample must you collect to Dx Y pestis?
Blood, bubo aspirate, or sputum, use std. micro techniques by hand to see what it is.
