Micro Flashcards
1
Q
What is the MOA of sulbactam, tazobactam, clavulinic acid?
A
beta lactamase inhibitors
2
Q
What causes a mono-spot negative mono-like syndrome?
A
CMV
3
Q
What type of leprosy has a TH1 response?
A
Tuberculin
- IL-2, TNF-g, IL-12
- induration with lepromin skin test
- Limited disease
4
Q
What type of leprosy has a TH2 response?
A
Lepromatous
- IL-4, IL-5, IL-10
- No reaction to lepromin skin test
- Disseminated disease, weak immune system
5
Q
How does Hep B help Hep D infet?
A
Hep B is required to COAT the HDAg
“hey BuDdy, I’ll get to your COAT”
6
Q
What part of the spinal cord does neurosyphilis affect?
A
Dorsal columns, hence Tabes Dorsalis
7
Q
What are some symptoms of Tabes Dorsalis?
A
A-R pupils Paresthesia Lack of proprioception Ataxia \+ Romberg Bladder incontinence
8
Q
How does integration of HBV into the genome of hepatocytes stimulate HCC?
A
Viral product of HBV increases insulin-like growth factor > proliferation
HBV suppresses Rb
9
Q
What symptoms characterize the measles prodrome?
A
CCCK
Cough
Coryza
Conjunctivitis
Koplik spots
Rash begins in 1-2 days
10
Q
What forms of malaria have fevers at 48 hour intervals?
A
Vivax and Ovale
11
Q
What are the forms of malaria (vivax and ovale) in the:
- Liver (active)
- Blood
- Liver (latent)
A
- Liver (active): trophozoites
- Blood: merozoites
Liver (latent): hypnozoites
12
Q
What is the treatment for malaria (vivax and ovale)?
A
Chloroquine for acute + Primaquine for hypozoites
13
Q
HIV structural proteins encoded by:
gag
A
p24 + p7: nucleocapsid proteins
14
Q
HIV structural proteins encoded by:
pol
A
Reverse transcriptase
15
Q
HIV structural proteins encoded by:
env
A
gp120 + gp41: envelope glycoproteins
Bind CD4
Mediate viral absorption
16
Q
Temporal lobe aphasia, olfactory hallucination caused by reactivation of a virus on the trigeminal ganglion
A
Herpes encephalitis
17
Q
Caused by point mutations in viral genome
Genetic drift or shift?
A
Drift
18
Q
Caused by exchange of genome by segmented virus
Genetic drift or shift?
A
Shift
19
Q
What viruses can undergo genetic shift?
A
Influenza, orthomyxoviruses, rotavirsues
20
Q
What are the names and functions of the Diphtheria toxins?
A
B: binding (esp. heart and neuronal tissue)
A: active (EF2 > stops host cell protein synth)
Note: A stains with Aniline dye
21
Q
What is the most common cause of retinitis in AIDS patients?
A
CMV
CD4
22
Q
What is the treatment for CMV retinitis?
A
Gancyclovir
23
Q
Cause of hydrocephalus + intracranial calcifications + chorioretinitis in newborns
A
Congenital Toxoplasmosis
Avoid cat poop while pregnant.
24
Q
Congenital toxoplasmosis is acquired…
- Transplacental
- Intrapartum
- Breast milk
A
Transplacental (in utero)
25
What happens when you mix Metronidazole and alcohol?
Disulfuram-like reaction: flushing, headache, N/V, cramps
26
What is the MOA of cord factor in TB?
Inhibits neutrophils
Destroys mitochondria
Releases TNF
27
What does the presence of cord factor indicate in TB infection?
Virulence
28
How does this intracellular organism survive in macros?
Salmonella
Blocks phagolysosome fusion
29
How does this intracellular organism survive in macros?
Tuberculosis
Blocks phaglysosome fusion and acidification
30
How does this intracellular organism survive in macros?
Listeria
Escapes phagolysosomes into the cytosol
31
How does this intracellular organism survive in macros?
Shigella
Escapes phagolysosomes into the cytosol
32
Intracellular organisms require what kind of immune response to kill them?
Cell-mediated immunity. Complement or Abs will not do it.
33
Morphology of Hep E
Unenveloped ssRNA virus
34
Spread of Hep E
Fecal oral
35
What population is affected by Hep E?
Pregnant women
36
What virus causes pharyngoconjunctivitis?
Adenovirus
- Pharyngitis
- Conjunctivitis
- Cervical LAD
Seen in close quarters
37
What are some nucleoside analogues?
Acyclovir
Valacyclovir
Gancyclovir
Famicyclovir
38
What enzyme do the nucleoside analogues require?
Viral kinase to activate
39
What are the nucleotide analgoues?
Cidofovir, Tenofovir
40
What enzyme do the nucleotide analogues requrie?
None!
41
What is the Rx for VZV, CMV, and EBV--nucleoside or nucleotide inhibitors?
Nucleotide (Cidofovir, Tenofovir) because they lack thymidine kinase to activate nucleoside inhibitors
42
What part of the brain is damaged in Tabes Dorsalis?
Midbrain (tectum)
43
What are the adverse effects of protease inhibitors?
Lipodystrophy
Hyperglycemia (increased insulin resistance)
Inhibition of p450
44
Antigen that is released during division or bacteriolysis of Gram negatives and causes sepsis
LPS
45
Angiten released from Gram negatives that causes shock by activating the inflammatory cascade
Lipid A
46
Antigen that is an outer membrane polysaccharide in the cell wall of Gram negatives
O antigen
47
What are some means of inactivating HAV?
```
Chlorination of water
Bleach
Formalin
UV
85 degrees C for 1 min
```
48
Bacterial cause of meningitis with this pattern of invasion:
pharynx > lymphatics > meninges
H flu
49
Bacterial cause of meningitis with this pattern of invasion:
middle ear > contiguous tissue > meninges
S pneumo
50
Bacterial cause of meningitis with this pattern of invasion:
traumatic wound leaking CSF > meninges
S aureus
51
Bacterial cause of meningitis with this pattern of invasion:
pharynx > blood > choroid plexus > meninges
Neisseria
52
Bacterial cause of meningitis with this pattern of invasion:
primary lung focus > blood > meninges
TB
53
HIV + seizures + ring enhancing lesions think..
Toxoplasmosis
54
Rx for Toxoplasmosis
Pyrimethamine and Sulfadiazine
55
Cause of HIV esophagitis with:
Gross--gray pseudomembranes
Histo--yeast cells, pseudohyphae
Candida
56
Cause of HIV esophagitis with:
Gross--punched out lesions, vesicles
Histo--eosinophilic intranuclear inclusions
HSV
57
Cause of HIV esophagitis with:
Gross--linear ulcerations
Histo--intranuclear and cytoplasmic inclusions
CMV
58
Aerobic, serpentine bacteria with medusa heads
Bacillus anthracis
59
Bacterial cause of wool-sorter's disease
Bacillus anthracis
60
Bacterial cause of mediastinal hemorrhage
Bacillus anthracis
61
Virulence factors of Bacillus anthracis
3 part anthrax toxin
| Antiphagocytic capsule
62
Drugs for MRSA
Vancomycin
Linezolid
Daptopmycin
63
What is a strain of E coli that does not ferment sorbitol or make glucuronidase?
EHEC O157:H7
64
What is the pathogenicity of E Coli O157:H7
Shiga like toxin inactivates 60S ribosomal subunit, ceasing protein synthesis > death
65
What food is EHEC associated with?
Undercooked beef
66
Barrier to antibiotic penetration and host defenses synthesized by Staph epidermidis
Biofilm
67
What organisms produce biofilm?
```
Staph epi
Strep viridans
Strep mutans + sanguis
Pseudomonas
H flu
```
68
5 catalase + organisms by which Chronic Granulomatous Disease NABSS you:
```
Noardia
Aspergillus
Burkholderia
Serratia
Staph aureus
```
69
MOA of Raltegravir
Integrase inhibitor
| Stops mRNA transcription by stopping HIV genome from integrating into the host
70
What cofactors does H flu require in growth medium?
```
Factor V (NAD): remember 5, nickel, NAD
Factor X (hematin): remember hemaTEN
```
71
Can grow on sheep's blood agar with Staph aureus
H Flu
Staph aureus makes Factor V and lyses the RBCs to release Factor X
72
Rash moving from face to trunk + post-auricular cervical LAD
Rubella (German measles)
| - Togavirus
73
Rash moving from face to trunk that darkens and coalesces
Rubeola (measles)
| - Paramyxovirus
74
Papulovesicular rash from the trunk moving out
```
Varicella Zoster (chicken pox)
- Herpesvirus
```
75
Rash moving from trunk out, transient with fever
Roseola
| - Herpesvirus
76
What are the side effects of Amphotericin?
Renal toxicity
| Severe hypokalemia, hypomagnesemia
77
How does meningococcus attach to epithelial surfaces like the nasopharynx?
Pilus
78
What are 3 non TB uses for Rifampin?
Meningitis (prophylaxis for contacts)
Leprosy
Staph endocarditis
79
What is the most common cause of aseptic meningitis?
Enteroviruses
80
Why are enteroviruses named such?
They replicate in the GI tract
Do not cause gastroenteritis! Instead:
- Polio
- Cocksackie
- Echo
81
What is the treatment for H Pylori?
Triple Therapy
2 antibiotics: metronidazole, tetracycline, amoxicillin, clarithromycin + 1 PPI (omeprazole +/- bismuth)
14 days
82
What antigen does the influenza vaccine target?
Hemagluttinin
83
What is the MOA of hemagluttinin of influenza virus?
Mediates viral entry into cells
84
What is the MOA of Oseltamivir against influenza virus?
Prevents neuraminidase cleavage of sialic acid, thereby preventing release of viral progeny
85
How do IFN-a and IFN-b combat influenza virus?
They are released by infected cells to induce antiviral synthesis in neighboring cells, thereby preventing spread by suppressing viral replication and assembly
86
What is the most common viral cause of aplastic crisis?
Parvovirus B19
- Non-enveloped ss DNA virus
- Infects erythrocyte precursors in bone marrow
87
Gram - bacillus, anaerobe, part of intestinal flora
Common cause of intra-abdominal infections and abscess formation, as well as appendicitis
Bacterioides fragilis
88
What is the rx for B fragilis?
Piperacillin-tazobactam
89
N/V and cramps within 6 hours after eating mayo at a picnic. Diagnosis?
Staph aureus
90
What toxin is responsible for Staph food poisoning?
Pre-formed heat stable enterotoxin
91
What are 3 diseases caused by Staph "exotoxin" release?
1) Toxic Shock
2) Scalded Skin
3) Gastrotenteritis
92
What is the most common cause of viral encephalitis in both immunocompetent and compromised?
HSV
93
What part of the brain does HSV encephalitis affect?
Temporal lobe, causing seizure, personality change, and psychosis along with more general fever, headache, and malaise
94
What are non-specific screening tests for syphilis?
RPR and VDLR
95
What is the definitive test for syphilis?
FTA-ABS
96
What syphilis test involves adding patient serum to cardioplipin, lecithin, and cholesterol, looking for flocculation?
RPR--will see flocculation if patient has serum Abs against destroyed cell products
97
Name the type of viral exchange:
when 2 viral strains infect 1 cell and the product involves surface proteins of one virus and the genome of the other
Phenotypic Mixing
- Note: if neither original organism was cytopathic, the new arrangement will not be either
98
Name the type of viral exchange:
uptake of DNA that changes genetics of host but not progeny virions
Transformation
99
Name the type of viral exchange:
genetic exchanges between 2 virus strains with non-fragmented ds DNA
Recombination
100
Name the type of viral exchange:
host cells co-infected with 2 strains that exchagne whole genome segements, altering capsule proteins of progency
Reassortment
101
Pharyngitis (gray exudate) + strawberry tongue + sandpaper rash starting in the axilla, groin, and neck that generalizes. Diagnosis?
Scarlet fever
102
What is the causal organism of Scarlet Fever?
GAS
103
Because Scarlet Fever is caused by GAS, what are possible sequelae?
Glomerulonephritis
| Acute Rheumatic Fever
104
URI followed by red, flushed cheeks in a child. Diagnosis?
Erythema infectiosum/Fifth Disease, caused by Parvo B19
105
What type of cell does Parvo B19 infect preferentially?
Erythroid precursors
106
Where does Parvo B19 replicate?
Bone marrow
107
Dimorphic fungus that lives intracellularly in macrophages
Histoplasma capsulatum
108
Metronidazole + alcohol causes...
Disufuram-like effect
Metronidazole is an acetaldehyde dehydrogenase inhibitor
109
"Mold in the cold, yeast in the heat"
Name the dimorphic fungus:
Branching hyphae
Cigar-shaped yeast
Sporothrix
110
"Mold in the cold, yeast in the heat"
Name the dimorphic fungus:
Thick walled spherules with endospores
Coccidioides
111
"Mold in the cold, yeast in the heat"
Name the dimorphic fungus:
Branching hyphae
Yeast within macros
Histoplasma
112
"Mold in the cold, yeast in the heat"
Name the dimorphic fungus:
Branching hyphae with doubly refractile wall
Single, broad based bud
Blastomyces
113
"Mold in the cold, yeast in the heat"
Name the dimorphic fungus:
Blastoconidia
Paracoccidioides
114
Which hepatitis on biopsy looks like:
- Cytoplasm full of spheres and tubules
- Finely granular eosinophilic appearance ("ground glass")
Hep B
115
Which hepatitis on biopsy looks like:
- Lymphoid aggregates in portal tracts
- Focal areas of microvesicular stenosis
Hep C
116
Why doesn't infection confer immunity to Neisseria Gonorrhea?
Antigenic variation in membrane proteins
117
E. Coli Virulence Factors:
Name the disease caused by....
LPS
Septic shock + bactemia
Through macrophage activation of IL-1, IL-6, TNF-a
"will that Like Produce Shock?"
118
E. Coli Virulence Factors:
Name the disease caused by....
K1 Capsular Polysaccharide
Neonatal meningitis
Through preventing phagocytosis and complement mediated lysis
"K for kids"
119
E. Coli Virulence Factors:
Name the disease caused by....
Verotoxin (Shiga-like toxin)
Bloody diarrhea (Gastroenteritis)
Through inactivating 60S, stopping protein synthesis
120
E. Coli Virulence Factors:
Name the disease caused by....
Heat-stable/labile enterotoxins
Watery diarrhea (Gastroenteritis)
Through fluid and electrolyte secretion
"Lose water in the heat"
121
E. Coli Virulence Factors:
Name the disease caused by....
P fimbriae/pili
UTI
Through adhesion to urothelium
"P for pee"
122
Desquamative illness + hypotension + multisystem dysfunction caused by Staph aureus
Toxic Shock Syndrome
123
What is the immune cascade that causes Toxic Shock Syndrome
```
Superantigens interact with MHC on APC and variable region on T cell >
Widespread T cell activation >
IL-2 release >
Macros > IL-1 + TNF >
Immune cascade continues
```
124
Gram + anaerobic spore forming bacillus that releases toxin by autolysis
Clostridium botulinum
125
Used as rx for focal dystonia, achalasia, spams
Botulinum toxin
126
Gram + bacillus found in soil that causes gas gangrene and gastroenteritis
Clostridium perfringens
127
What is the MOA of Staph aureus' Protein A?
Binds Fc of IgG, preventing complement activation
| Found on cell wall
128
Non motile, non lactose fermenting, oxidase - gram - rod that does not produce H2S on triple sugar iron agar
Shigella
129
Invades M cells
Shigella
130
Escapes phagolysosome and spreads via actin polymerase
Shigella
131
Only fungus with polysacharide capsule
Cryptococcus
This makes it stain red with mucicarmine, clear with unstained zone on India ink
132
What is the transmission of Campylobacter and common vectors?
Fecal oral, from
Domestic animals: cattle, sheep, chickens, dogs
Contaminated food: poultry, milk
133
On what agar is Cryptococcus cultured?
Sabouraud's
134
What stains are good for Cryptococcus on CSF? Or tissue?
CSF: India ink and latex agglutination
Tissue: Methenamine silver (GMS), Mucicarmine
135
Viral cause of:
- Hemorrhagic cystitis in children
- Tonsilitis
- Conjunctivitis
Adenovirus
136
What is the vector for Schistosomiasis?
Freshwater snail (not found in US)
137
What type of schistosomiasis does S. hematobium cause?
Urinary
- Hematuria, dysuria
- Hydropherosis, pyelonephrosis, SCC bladder
138
What type of schistosomiasis does S. mansoni cause?
Intestinal: diarrhea, ab. pain, iron def. anemia
&
Hepatic: HSM, periportal "pipestem" fibrosis, portal HTN
139
What type of schistosomiasis does S. japonicum cause?
Intestinal: diarrhea, ab. pain, iron def. anemia
&
Hepatic: HSM, periportal "pipestem" fibrosis, portal HTN
140
What is the MOA of Zidovudine aka AZT?
NRTI
Binds reverse transcriptase and is integrated into genome
Doesn't have 3' - OH, so can't make 3-5' phosphodiester bond
141
What are two antibiotics that are paired with another drug to prevent renal secretion?
Imipenem/Cilastatin
Penecillin/Probenecid
142
What is the Rx for HCV and CMV?
Ribavarin
143
What are the causes of Impetigo?
Staph aureus & GAS (pyogenes, viridans, pneumo)
144
What viruses use host DNA + RNA polymerases to replicate in the nucleus?
Papovaviruses (Papilloma, polyoma)
145
HBV Protein Sequences
Nucleocapsid core protein that assembles virion
HBcAg
146
HBV Protein Sequences
Core + precore, assembles + secretes, indicates infectivity
HBeAg
147
HBV Protein Sequences
Non-infectious envelope glycoprotein
Spheres + tubules in structure
Huge quantity secreted
HBsAg
148
HBV Protein Sequences
Uses reverse transcriptase to replicate genome
DNA polymerase
149
HBV Protein Sequences
Transcription transactivator necessary for replication
De-regulation of hepatocyte replication
Causes HCC
HBx
150
Hepatitis transmission:
HAV
Fecal oral
151
Hepatitis transmission:
HBV
Sex >
Drugs, blood transfusion
152
Hepatitis transmission:
HCV
Drugs (IV)
153
Hepatitis transmission:
fecal oral
HAV
154
Hepatitis transmission:
Sex
HBV
155
Hepatitis transmission:
Drugs
HCV > HBV
156
Bloody Diarrhea is caused by...
SECSEY
```
Salmonella
Ecoli (invasive)
Campylobacter
Shigella
Entamoeba
Yersinia
```
157
Watery Diarrhea is caused by...
Vibrio
Ecoli (toxogenic)
B cereus
Staph aureus
Giardia
Cryptosporidium
Cylcospora
Microsporidia
158
Name the pathogen:
Paroxysmal cough
Toxin that converts ATP > cAMP, disturbing cell signalling and preventing neutrophil chemotaxis
Increased lymphos in circ, but not clearing infection
Bordatella Pertussis
159
Non-lactose fermenting oxidase (-) organism with capsule that prevents opsonization
Common cause of what in Sickle Disease?
Osteomyelitis
| Salmonella
160
Main cause of acute airway obstruction in infants
RSV causing viral bronciolitis
Rx: Ribavarin
161
What is a toxin that cleaves IgA at the hinge region, thereby increasing mucosal adhesion and penetration?
IgA protease
162
What organisms have IgA protease?
N gonorrhea
N meningitidis
Strep pneumo
H flu
163
What organism is the cause of malignant otitis externa?
Pseudomonas: non-lactose fermenting Gram - ox + rod
| - Ear pain and granulation tissue in ear canal
164
What is the mechanism of drug resistance in E coli?
Acquired plasmid R via conjugation
165
What receptors mediate HIV entry?
CD4
| CCR5 chemokine co-receptor
166
What accounts for the variability of HCV (quasi species)?
No 3-5 exonuclease, so no proofreading
| Leads to genetic variability
167
Strep pyogenes virulence factors:
Stops phagocytosis + complement
Protein M (Major!)
168
Strep pyogenes virulence factors:
lyses RBCs (beta hemolysis) + PMNs
Streptolysin O
169
Strep pyogenes virulence factors:
depolymerizes DNA in pus, dissolves PMNs, allows spread
DNAse
170
Strep pyogenes virulence factors:
Plasminogen > plamin > decreased fibrin, allows spread
Streptokinase
171
Strep pyogenes virulence factors:
Capsular antigen, antiphagocytic
Hyaluronate
172
Selective medium, chocolate agar + vanco, polymixin, nystatin, and TMP, grows...
Neisseria Meningitidis
| Thayer Martin medium
173
Strep pneumo, N meningitidis, and H flu all have vaccines directed against...
Capsular polysaccharides
174
Influenza vaccine is a killed vax against....
HA: hemagluttinin
175
What bacteria causes chronic infection in CF patients because of its biofilm in the LRT?
Pseudomonas
- Has tolerance to antibiotics
- Decreased phagocytosis
176
Mycobacterium that prefers cool temps
| Stocking glove distribution of loss of sensation
Mycobacterium leprae
177
What type of cancer does EBV cause?
Nasopharyngeal carcinoma
178
Inhibits cell wall synthesis by inhibiting B-glucan carbohydrates
Caspofungin
