Microbiology Flashcards
(259 cards)
1
Q
THis is a collection of pus (neutrophils) that has accumulated within a tissue because of an inflammatory process.
A
Abscess
2
Q
This is an infection of the hair follicle, which may progress to cutaneous tissue, leading to furuncles (boils).
A
Folliculitis
3
Q
These are large, painful, raised nodules that contain underlying collections of dead and necrotic cells in cutaneous tissues.
A
Furuncles (boils)
4
Q
These are an extension of furuncles into subQ tissues.
A
Carbuncles
5
Q
This is a spreading infection that is limited tot he epidermis and presents as a bullous, crusted, or pustular eruption of the skin.
A
Impetigo
6
Q
What characteristic color are the lesions in impetigo?
A
Honey-crusted lesions
7
Q
This is a spreading infection that involves the blocking of dermal lymphatics and presents as a well-defined, spreading erythematous inflammaton, and often accompanied by pain and fever.
A
Erysipelas
8
Q
In which age does a malar (butterfly) bright red rash occur on the face as an erysipelas?
A
Children
9
Q
This is a spreading infection where the focus of the infection is in the subQ fat.
A
Cellulitis
10
Q
This is the inflammatory response to infection of the soft tissue below the dermis, rapid spread along the fascial planes, disrupting the blood suppy.
A
Necrotizing fasciitis
11
Q
Ischemia of the muscle layer can cause this condition, where there is gas resulting from the fermentative metabolism of anaerobic organisms.
A
Gas Gangene
12
Q
This is a flat red local inflammation in response to an infiltrating leukocyte (esp their toxins in the dermis).
A
Macule
13
Q
This is a raised red inflammation with invasion of neighboring tissues.
A
Papule
14
Q
This is a small blister, from a microbe that invades the epithelium (HSV, VZV).
A
Vesicle
15
Q
This is the ruptured epithelium from a vesicle, where the microbe is discharged.
A
Ulder
16
Q
This is when the microbe grows into the epitheliu, which proliferates, and the microbe sheds with epithelial cells (wart).
A
Papilloma
17
Q
What is the most common cause of skin infections?
A
S. aureus
18
Q
What are the lab chracteristics of S. aureus?
A
G+ cocci
Catalase +
Coag +
B-hemolytic
19
Q
After S. aureus invasion to the skin, what forms within 2-4 days?
A
Boil
20
Q
After the boil in the S. aureus forms, it triggers an inflammatory response and the invasion of Neutrophils to cause what to form?
A
Abscess
21
Q
What happens to the abscess in S. aureus infections?
A
Expands and eventually drains.
22
Q
What is the DOC for bacteria that produce B-lactamase?
A
Methcillin
23
Q
What is the DOC for MSSA?
A
Nafcillin
susceptible
24
Q
What is the DOC for MRSA?
A
Vancomycin
25
Nasal carries of MRSA can be treated with nasal creams, like what drug?
Mupirocin
26
What does MRSA secrete, which has a lower affinity for B-lactams than normal PBPs, allowing it to continue cell wall synthesis when other PBPs are inhibited.?
PBP2a
27
What gene codes for PBP2a?
MecA
28
Vancomycin resistance comes from a ligase producing pentapeptides terminating in what sequence?
D-Ala D-lactate
29
Which Van genes can be transmitted (chromosomal or plasmid) and inducible?
VanA and VanB can be transmitted and is inducible.
VanD cannot be transmitted (chromosomal) and expressed constitutively
30
True or False: S. aureus have decreased susceptibility to vancomycin from Van genes.
False
Decreases susceptibility is associated with cell wall composition (↑ thickness) and not a Van gene.
31
Which Van comes from VRE from a plasmid and has high-level glycopeptide resistance?
VanA gene
32
Which toxin causes SSSS?
Exfoliatin or SSS toxin
33
Which ages is SSSS common?
Neonates
34
What is the manifestations of SSSS?
Large blisters with clear fluid and skin loss, mimics burns.
35
What is the mechanism of action of the TSST1 to cause TSS?
Superantigen (overstimulation of T cells and macrophages)
36
What "device" causes young girls to be susceptible to TSS?
Tampons
37
What are the Sx to TSS?
Fever, hypoTN, diffuse macular erythematous rash followed by desquamation of the skin (esp soles/palms)
38
What is the main virulence factor for S. pyogenes?
M protein
39
How does M protein provide resistance from S. pyogenes infections?
Inhibition of opsonization
40
After 1-2 days, there is an inflammatory response made from S. pyogenes infections, and it spreads using what protein?
Hyaluronidase
41
What are the superantigens called in S. pyogenes?
SPE's (A, B, and C)
42
This is the superficial infection of S. pyogenes.
Impetigo
43
What is the deeper infection of the dermis called in S. pyogenes, where there can be bacteriemia and death?
Erysipelas
44
What is the condition from S. pyogenes where there is immune complex deposition on the BM of the glomerulus 2-3 weeks after infection?
PSGN
45
What is teh condition from S. pyogenes infection that is a mixed infection of anaerobes and faculative anerobes, and there is widespread necrosis of the skin and possible death?
Necrotizing fasciitis
46
What are the 2 main suspects to Cellulitis?
S. pyogenes
| S. aureus
47
Which bacteria is G+, cocci, catalase -, B hemolytic, bactitracin sensitive, PYR+, and ASO+?
S. pyogenes
48
What is the source for S. pyogenes cellulitis?
Normal flora --> trauma causes inoculation
49
Which bacteria is G+, cocci, catalase +, coag +, and mannitol fermenting?
S. aureus
50
Which VF from S. aureus binds the Fc portion of host IgG?
Protein A
51
What cause of cellulitis is a G+ rod, catalase-, non-spore forming, and nonmotile?
Erysipelothrix rhusiopathiae
52
What is the host for Erysipelothrix rhusiopathiae infections?
Pigs
53
What is the cause of cellulitis that is G- rod, comma shaped, lactose non-fermenter, oxidase +, and motile?
Vibrio vulnificus
Vibrio algionlyticus
54
Where can u get vibrio?
Marine invironments
55
Which bug can cause gas gangrene from the soil and feces?
C. perfringens
56
What does the Lecithinase (alpha toxin) cleave on the host cell membranes, leading to cell lysis and death?
Phospholipids
57
What are the 2 risk factors for gas gangrene?
Ischemic vascular disease
| Peripheral arteriosclerosis
58
Which specialized agar differentiates C. perfrinegens from other bacteria?
+ Nagler rxn (egg yolk agar)
59
These are greasy plugs of keratin, sebum, and bacteria, capped by a layer of melanin.
Comedones (black heads)
60
What is the main cause of comedones, which an aerotolerant anaerobic G+ rod?
Proprionibacterium acnes
61
What hormones ↑ in the body to ↑ sebum and keratinization/desquamation in pilosebaceous ducts to cause acne/comedones?
Androgenic H's
62
These are acid fast rods that stain with Ziehl-Neelsen or auramine stain.
M. leprae
63
Which 2 cells does M. leprae grow in?
Skin histiocytes
| Schwann cells
64
True or False: like TB, M. leprae can be grown in vitro.
FALSE
65
Where can u find M. leprae in infected individuals?
Nasal secretions
66
How long is the incubation period for M. leprae?
Years
67
This is the form of leprosy where there is a vegrous CMI response, leading to phagocytic destruction of bacteria and exaggerated allergic response.
Tuberculoid leprosy
68
What is a common Sx of Tuberculoid leprosy?
Local anethesia from thickening of peripheal nerves
69
What is the CMI response to M. leprae to cause Lepromatous leprosy?
Weak CMI response
70
Which is worse, Lepromatous leprosy or Tuberculoid?
Lepromatous leprosy
71
What are the Sx to Lepromatous leprosy?
Loss of eyebrows
Thickening and enlargement of nostrils, ears, and cheeks
Lion-like face
Lose nasal septum
72
Which form of Leprosy (L or T) will have numerous organisms on staining?
Lepromatous leprosy
73
Which mycobacterium do u associate with fish tanks?
M. marinum
74
What usually happens to you to allow M. marinum into your skin?
Some sort of trauma
75
What is the initial lesion of M. marinum after 2-8 weeks?
Small papules --> enlarge and may ulcerate.
76
What are Mycobacterium genus that causes chronic, relatively painless cutaneous "buruli" ulcers?
M. ulcerans
77
Where can u find M. ulcerans?
Africa and Australia
78
Which form of fungi (yeast or mold) are unicellular, reproduce by budding, and can form pseudohyphae?
Yeast
79
So we can guess that molds are multicellular and have hyphae, but what are hyphae?
Elongated tubes of cells attached end to end
80
What are the form of hyphae that have membranes separating individual cells?
Septate hyphae
81
What are the 4 dimorphic fungi?
C. immitis
H. capsulatum
B. dermatidis
S. schenkii
82
Tinea pedis and vaginal candidiasis are of what type of mycoses infection?
Superficial
83
What is involved in subcutaneous mycoses?
Nails and deeper layers of the skin
84
What is it called when there are mycoses of the internal organs?
Systemic/Deep mycoses
85
Malassezia furfur- conditions
Pityriasis or Tinea versicolor
86
Malassezia furfur- lesion morphology
Hypo or Hyperpigmented macules that coalesce to form scaling plaques.
87
Malassezia furfur- Sx
Itchy lesions, resolve spontaneously
88
Malassezia furfur- findings on KOH prep
Spaghetti and meatballs
89
Malassezia furfur- Tx
Miconazole, selenium sulfide
90
This is is a common label for a group of 3 types of fungus that common causes skin disease in animals and humans.
Dermatophytes
91
What contacts the skin to cause dermatophytes?
Anthospores
92
What are the most common cause of dermatophyte infections, where the anthrospores are spread shed from human skin scales and hair?
Antropohphilic
93
What is the most common dermatophyte from animals?
Zoophilic
94
Where do the following Zoophilic dermatophytes come from?
Trichophyton verrucosum
T. mentagrophytes
Microsporum canis
Trichophyton verrucosum- cows
T. mentagrophytes- rodents
Microsporum canis- dogs and cats
95
What are the type of dermatophytes from soil, and includes species like Microsporum gypseum?
Geophilic
96
Which epidermal protein do the tinea spp like to infect?
Keratin (skin, hair, nails)
97
What is the typical lesion morphology in tinea infections?
Serpentine scaling patch with raised margin
98
Which tinea spp infects the hair and scalp, leading to hair loss?
Capitis
99
Which tinea spp infects the body?
Corporis
100
Which tinea spp infects the crotch?
Cruris
101
Which tinea spp infects the feet?
Manuum and Pedis
102
Which tinea spp infects the nails?
Unguium
| these names are freakin weird
103
What are the 3 genera responsible for dermatophytoses?
Microsporum
Epidermophyton
Trichophyton
104
What type of "light" do you use to see the microsporum spp?
UV-emitting Wood's light
105
Using a UV-emitting Wood's light, what color do the hairs flouresce if they are contaminated with microsporum spp?
Bright green
106
If you have a bright red rash in a skin fold because youre 500 pounds and you need an innocent EMT working in the ICU to help cleanse your cheesy smelly skin folds, what fungi is prolly growing there?
Candida
107
Which WBC are important for the prevention of superficial candida infections?
T-cells
108
Which WBC are important for the prevention for hematogenous spread of candida?
Neutrophils
109
If you get pricked by a rose bush and develop a small papule that subsequently spreads to the lymphatics, what fungi might be the cause?
Sporothrix schenckii
110
What agar is used to Dx Sporothrix schenckii?
Sabouraud dextrose agar
111
Which 3 viruses do not spread systemically?
Papillomas
Molluscum contagiosum
Orf
112
What is the type of lesion of HSV, VZV, CoxA, and CoxB?
Vesicular
113
A vesicular lesion shows a icosahedral, non-enveloped, dsDNA virus. What is the cause?
Papillomavirus
114
Which HPV types cause plantar warts?
1 and 4
115
Which HPV types cause genital warts?
6, 11
116
Which HPV types cause warts on the knees and fingers?
2, 3, 10
117
Papillomavirus- transmission
Direct contact
118
Papillomavirus- layer of skin infected
Basal layer
119
Papillomavirus- cancer associations
Cervical
Vulva
Penis
Rectum
120
Molluscum contagiosum- genus
poxvirus
121
Molluscum contagiosum- lesion morphology
Fleshy, umbilicated
122
Molluscum contagiosum- transmission
Contact
123
Orf- host
Sheep
124
Orf- lesion morphology
Papulovesicular, generally on hands, may ulcerate
125
What type of host envelope do the herpesviridae acquire?
Nuclear membrane envelope
126
What type of cells are seen on Tzanck smear for herpes?
Multinucleated Giant cells
127
What "bodies" are seen in herpes?
Eosinophilic Cowdry intranuclear inclusion bodies
128
HSV1- diseases
Gingivostomatitis, keratoconjunctivitis, herpes, ENCEPHALITIS
129
HSV1- transmission
Kiss kiss
130
HSV1- location for focal necrotic lesions
Temporal lobe
131
HSV1- site of latency
Trigeminal gangkion
132
HSV1- triggers
stress
133
HSV2- diseases
genital herpes, neonatal herpes
134
HSV2- transmission
sexual contact
135
HSV2- Sx
local vesicular lesions
136
HSV2- group at complication risk
Pregnant ladies
137
HSV2- site of latency
Sacral ganglia
138
HSV2- trigger
Stress
139
VZV- diseases
varicella (chickenpox) and zoster (shingles)
140
VZV- transmission
Respiratory secretions
141
VZV- morphology of vesicles in respiratory tract
Dew on a rose petal
142
VZV- primary presentation
Rash with vescicles (varicella), resolves in 2 weeks
143
VZV- secondary presentation
Shingles, painful vesicular rash over 1 dermatome
144
VZV- 3 complications
Interstitial PNA
CNS involvement
Blindness
145
VZV- site of latency
DRG
146
VZV- triggers
Stress, IC state, ↑ age, local injury
147
Which viral family does coxsackie virus A16 belong to?
Picornaviruses
148
Coxsackie A16- viral characteristics
ss + linear RNA, nonenveloped, iscosahedral
149
Coxsackie A16- 2 diseases
Herpangina (mouth blisters, fever)
| Hand, Foot, Mouth disease
150
Coxsackie A16- transmission
Fecal oral or direct contact or aersolization
151
Parvovirus B19- genome morphology
ssDNA
152
Parvovirus B19- 2 diseases
```
Erythema Infectiosum (5th disease)
Aplastic anemia crisis
```
153
Parvovirus B19- 5th disease Sx
Cheek rash (slapped cheeks) --> move down to trunk
154
Parvovirus B19- transmission
Respiratory aerosols
155
Parvovirus B19- vertical transmission conditions
Fetal anemia
| Hydrops fetalis
156
HHV6- disease
Roselia
157
HHV6- Sx
Fever followed by a lacy body rash within 2 days
possible szrs
158
HHV6- transmission
Saliva
159
HHV7- disease
Roselia (though not as frequently)
160
HHV8- disease
Kaposi sarcoma
161
HHV8- pts at risk
AIDS
162
HHV8- lesion morphology
Nodular and dark (purplish)
163
HHV8- transmission
Secks
164
Poxvirus- morphology
Complex (not enveloped)
165
Poxvirus- site of replication
Cytoplasm (not in nucleus, despite being a DNA virus)
166
Since poxvirus replicates in the cytoplasm, what enzyme must it contain to replicate within the cytoplasm?
DNA-dependent RNA polymerase
167
Poxvirus- transmission
Person-person with skin lesions and via respiratory tract
168
Poxvirus- disease
Smallpox
169
Poxvirus- lesion morphology
Vasiculopapular rash with later scarring, especially on the face
170
Poxvirus- vaccine type
Live attenuated
171
What was it about the following things that made it possible for smallpox to be eradicated?
Subclinical features
Carriers
Host
Vaccine
No subclinical features
No carriers
Humans were the only host
Effective vaccine was available.
172
What was the most recent scare in the US related to smallpox due to?
Monkeypox
173
What was the carrier for monkeypox to infect 80 people in the US?
Prairie dogs
174
Measles- virus morphology
dsDNA, linear
175
Measles- transmission
Respiratory droplets
176
What was the name of the Arabian physician that first recognized measles over 1000 years ago?
Rhazes
177
Measles- first Sx
Runny nose, fever, cough, conjunctivits
178
Measles- lesion morphology
Koplik spots- white spots on buccal mucosa
179
Measles- spread of rash
Starts on the face and then spreads down the trunk to the limbs
180
Rubella- class of virus
Togavirus
181
Rubella- viral characterisitics
+ ssRNA, linear, icosahedral, envelope with E1, E2 surface glycoproteins
182
Rubella- transmission
Transplacental or Airborne
183
After entering the respiratory tract, where does rubella enter?
Lymph nodes and spleen
184
After multiplying in the lymph nodes, where does the virus then invade?
```
Respiratory tract
Skin
Placenta
Joints
Kidneys
```
185
What are the Sx of rubella invasion of the respiratory tract?
Sore throat, coryza, cough
186
What are the Sx of rubella invasion of the skin?
rash from forehead --> down
187
What are the Sx of rubella invasion of the placenta?
Congential rubella (PDA, cataracts, deafness, microcephaly)
188
What are the Sx of rubella invasion of the joints?
RA
189
R. rickettsi- disease
RMSF
190
R. rickettsi- vector
Wood tick (dermacentor andersoni)
191
R. rickettsi- spread of rash
palms/soles --> trunk
192
R. rickettsi- complications
edema + hemorrhage --> hypovolemia
193
R. rickettsi- area of infection in the US
North Carolina and Oaklahoma
194
Borrelia burgdoferi- disease
Lyme disease
195
Borrelia burgdoferi- vector
Ixodes tick
196
Borrelia burgdoferi- stages
1. erythema migrans
2. neuropathy
3. arthritis
197
Borrelia burgdoferi- rash morphology
Bulls eye that expands
198
Bacillus anthracis- disease
Anthrax
199
Bacillus anthracis- population at risk
herbivores
200
Bacillus anthracis- bacterium morphology
G+ rod (boxcar shaped)
201
Bacillus anthracis- capsule morphology
D-glutamic acid
| protein capsule. the only bacteria to have a protein capsule. super important
202
Bacillus anthracis- toxins
PA
EF- ↑ cAMP
LF- protease
203
Bacillus anthracis- skin manifestations
Painless ulcer with black eschar and edema called a malignant pustule
204
Bacillus anthracis- pulmonary findings
If inhaled --> hemorrhagic mediastinitis (widened) --> septic shock and death
205
Bacillus anthracis- GI findings
Ingestion of contaminated meats --> N/V, bloody diarrhea, death
206
Bacillus anthracis- Tx
PCN
207
Yersinia pestis- disease
Plague
208
Yersinia pestis- vector
fleas
209
Yersinia pestis- host
Rodents
210
Yersinia pestis- VF
Capsule
211
Yersinia pestis- morphology
non-motile, non-lactose fermenting, SAFETY PIN, growth at 4 degrees
212
Yersinia pestis- plague Sx
High fever, buboes
No human-human
213
Yersinia pestis- penumonic plague transmission
Human-human
214
Pasteurella multocida- host
Cats and Dogs
215
Pasteurella multocida- transmission
Cat/Dog bite
216
Pasteurella multocida- Sx
Cellulitis
217
Pasteurella multocida- lab characterisitics
G- rod, bipolar (safety pin) staining, capsule, musty odor
218
Pasteurella multocida- agar
Chocolate or blood at 37 degrees
219
Ancylostoma braziliense- appearance
Hookworm
220
Ancylostoma braziliense- host
Dog and cat intestines
221
Ancylostoma braziliense- people at risk
Kids who play with dog and cat poop
222
Ancylostoma braziliense- distribution
Beaches throughout the US
223
Ancylostoma braziliense- Sx
Severe erythematous and vesicular reactions
224
Ancylostoma braziliense- syndrome at risk
Loffler syndrome- transient pulmonary infiltrate with peripheral eosinophilia
225
Ancylostoma braziliense- Dx method
Skin biopsy shows larvae, Hx of playing with dog poop
226
Ancylostoma braziliense- Tx
Albendazole
227
Who deemed the name the "fiery serpent" to Dracunculus medinesis (aka the little dragon of Medina) with the Israelites at the Red Sea?
Moses
228
Dacunculus medinesis- appearance
Tissue-invading nematode from the Cyclops genus
229
Dacunculus medinesis- life cycle
larve ingested in drinking water --> penetrate GI wall --> maturation and mating in retroperitoneum --> subQ tissues --> ulcer --> larvae released once water contacts them.
230
Dacunculus medinesis- risky behavior to get infected
Drinking from "step wells"
231
Dacunculus medinesis- geographical distribution
Asia and Africa
232
Dacunculus medinesis- time until ulcer appearance
1 year
233
Dacunculus medinesis- Sx
Pain and erythema at the ulcer site
234
Dacunculus medinesis- Dx method
Flood the ulcer with water and wait until the worms crawl out
235
Dacunculus medinesis- Ancient method of Tx
Slowly wrapping the worm on a twig
236
Dacunculus medinesis- New Tx method
Surgical removal
237
Black widow (L. mactans)- distribution
Wood piles and brush in the South
238
Black widow (L. mactans)- pathogenesis
Sharp pain at bite --> local swelling, reness, and burning --> systemic signs like boardlike abd, chest pain, N/V --> Sx subside within 48 hours
239
Black widow (L. mactans)- toxin MOA
↑ presynaptic release of Ach
240
Black widow (L. mactans)- Tx
Antivenin to kids/weak people
241
Brown Recluse (Loxosceles)- pathogenesis
painless --> hours there is itching, swelling, and soreness and bleb at the site --> 3 days there is ulceration and radiating necrosis --> possible systemic problems.
242
How long does it normally take to have Sx if you've never been bit by scabies?
weeks-months
243
How long does it take to have Sx if you've been previously exposed?
1-4 days
244
What type of HS rxn causes the sensitization to scabies?
Type IV
245
Scabies- appearance
Oval, saclike body with claws
246
Scabies- Epidemiology
Found everywhere
247
Scabies- pathogenesis
Enter skin --> burrows under epidermis --> female lays eggs in skin burrows (esp folds) --> intense itching
248
Scabies- Dx method
Skin scrapings
249
Scabies- Tx
1% gamma benzene hexachloride (lindane)
5% permetrin cream (Enlimite) (this is better)
250
Lice (P. humanus capitis)- appearance
Elongated, wingless, flattened insets with 3 legs and a pretty mouth.
251
Lice (P. humanus capitis)- Epidemiology
KIDS
252
Lice (P. humanus capitis)- Sx
Intense itching, possible pruritic red papules around the ears, face, neck, or shoulders.
253
Lice (P. humanus capitis)- Dx
See the lice or eggs (nits)
254
Lice (P. humanus capitis)- Tx
Gamma benzene hexachloride (lindane)
255
Bedbugs (cimex letularis)- appearance
Reddish brown insect, 4-5mm, short wing pads but they cant fly
256
Bedbugs (cimex letularis)- epidemiology
all over, they feed at night
257
Bedbugs (cimex letularis)- Sx
Small red marks to hemorrhagic bullae, they bite in a linear fashion
258
Bedbugs (cimex letularis)- Dx
Pattern and location of bites, detecting blood spots on bedding or dead insects themselves.
259
Bedbugs (cimex letularis)- Tx
Topical palliatives for pruritis, antihistamines if severe dermatitis.
