Micro 3 Flashcards
1
Q
What are the envelope proteins of HIV
A
gp41 (transmembrane glycoprotein) and gp120 (docking glycoprotein) whic hare acquired through budding from host cell plasma membrane
2
Q
What is p24 in HIV?
A
Capside protein
3
Q
What is p17 in HIV?
A
Matrix protein
4
Q
HIV Genome?
A
diploid (2 molecules of RNA)
5
Q
3 genes of HIV and products
A
env (gp160=gp120 and gp41) gp120 attaches to CD4 cell and gp41 is for fusion and entry
gag (p24): capsid protein
pol is reverse transcriptase, aspartate protease, integrase
6
Q
Replication of HIV genome
A
reverse transcriptase makes dsDNA which integrates into the host genome
7
Q
What receptors does virus bind to?
A
On CD4+ cells: CD4 and CCR5 (early) or CXCR4 (late) co-receptor
On macrophages: CCR5 and CD4
8
Q
What people have immunity
A
CCR5 negative homozygotes. heterozygotes have a slwoer course
9
Q
What are the rule out and rule in tests of HIV?
A
Rule out is ELISA because of high sens, low spec.
Rule in is Western blot because of high spec., low sens.
10
Q
What are the thresholds for CD4 counts
A
Normal is 500-1500 cells/mm3.
AIDS is either <14%
11
Q
Where can you find false positives and false negatives in HIV?
A
Lots of false positives in babies because of anti-gp120 crossing the placenta.
False negatives in first 1-2 mo. of HIV infection
12
Q
Natural history of HIV mnemonic
A
4 F stages: Flu-like (acute), feeling fine (latent), falling count, final crisis
13
Q
Where does HIV replicate in latent phase
A
Lymph nodes
14
Q
What kind of cancer increases with HIV?
A
Non-Hodgkin lymphoma (large cell type) Often on oropharynx (waldeyer ring)
15
Q
HIV low-grade fevers, cough, hepatosplenomegaly, tongue ulcer
A
Histoplasma capsulatum (only pulmonary sxs in immunocompetent hosts)
16
Q
Derm and HIV
A
Candida, hairy leukoplakia, superficial vascular proliferation, superficial neoplastic proliferation of vasculature
17
Q
What causes vascular proliferation
A
Nonmalignant: Bartonella henselae (causes bacillary angiomatosis)
Malignant: HHV-8 (Kaposi’s sarcoma)
18
Q
HIV diarrhea
A
Cryptosporidium
19
Q
Neurologic and HIV
A
Abscesses, dementia, encephalopathy, meningitis, retinitis
20
Q
HIV abscess
A
Toxo
21
Q
HIV demenia
A
Directly associated with HIV
22
Q
HIV encephalopathy
A
JC virus reactivation (PML)
23
Q
HIV meningitis
A
Cryptococcus neoformans
24
Q
HIV retinitis
A
CMV
25
HIV associated cancers and pathogen
Non-Hodgkin lymphoma, Primary CNS lymphoma (both associated with EBV)
Squamous cell carcinoma of anus (HPV)
26
Difference between toxo and Lymphoma
Toxo has multiple ring-enhancing lesions
27
HIV respiratory issues
```
Interstitial pneumonia
invasive aspergillosis
PCP
Typical PNA
Tuberculosis like disease
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28
Biopsy of bartonella vs. kaposis
Bartonella has PMN inflammation, Kaposi's has lymphocytic inflammation
29
Normal prion protein name and conformation
alpha-helical prion protein (PrP^c) to pathological Beta-pleated form (PrP^sc) that is transmissible
30
Sporadic spongiform encephalopathy
Creutzfeldt-Jakob disease
31
Inherited prion disease
Gerstmann-Straussler-Scheinker
32
Acquired prion disease
Kuru
33
Day-care diarrhea
Yersinia enterocolitica
34
Salmonella and shigella lactose
Both NONfermenters
35
PNA in neonates (<4 wks)
Group B strep, E. coli
36
Most common PNA in children 4 wk-18 yr
RSV, Mycoplasma, C. trachomatis (infants-3yr), C. pneumoniae (school children), S. pneumo Runts May Cough Chunky Sputum
37
PNA Adults (18-40 yrs)
Mycoplasma, C. PNA, S. PNA
38
PNA Adults (40-65 yrs)
S. pna, H. flu, anaerobes, viruses, mycoplasma
39
PNA elderly
S. pneumo, flu, anerobes, h. flu, gram negative rods
40
Congenital Toxo
Classic triad: Chorioretinitis, hydrocephalus, and intracranial calcifications
41
Congenital Rubella
Classic triad: PDA (or pulm. artery hypoplasia), cataracts, and deafness +/- "blueberry muffin" rash
42
Congenital CMV
Hearing loss, seizures, petechial rash, "blueberry muffin" rash
43
Congenital HIV
Recurrent infections, chronic diarrhea
44
Congenital HSV-2
Encephalitis, herpetic lesions
45
Congenital Syphilis
Often stillbirth, hydrops fetalis; if child survives, facial abnormalities: notched teeth, saddle nose, short maxilla. Saber shins, CN VIII deafness
46
What is a saber shin
Anterior bowing of the tibia
47
What is hydrops fetalis?
Fluid accumulation in at least two fetal compartments like the pleural space, pericardium, peritoneum, subQ tissues
48
Fifth disease name and cause
Erythema infectiosum (Parvo B19) Slapped cheeks
49
Roseola cause
HHV-6
50
Roseola rash presentation
Macular rash over body after several days of high fever, can have febrile seizures, usually in infants
51
Measles rash
Paramyxovirus; begins at head and mvoes down; rash preceded by cough, coryza, conjunctivitis and blue-white Koplik spots on buccal mucosa
52
Rubella rash
Rash at head and moves down; leads to fine truncal rash; postauricular lymphadenopathy
53
Scarlet fever rash
Erythematous, sandpaper-like rash with fever and sore throat
54
Parvo B19 congenital
Can cause hydrops fetalis
55
Genital Chlamydia serotype
D-K
56
Lymphogranuloma venereum cause
C. trachomatis L1-L3
57
Strawberry cervix
Trichomoniasis
58
Lymphogranuloma venereum presentation
Infection of lymphatics; painless genital ulcers, painful lymphadenopathy (i.e. buboes)
59
Chancroid presentation
Painful genital ulcer, inguinal adenopathy
60
Fitz-Hugh-Curtis syndrome
Infection of liver capsule and "violin string" adhesions. Classically associated with gonorrhea, but actually more often due to Chlamydia
61
Unimmunized children neurologic disease
Meningitis due to HiB. It colonizes nasopharynx.
62
order of prevalence of encapsulated organism infection
S. pneumo >>> HiB > meningococcus
63
MOA trimethoprim
Inhibits dihydrofolate reductase
64
MOA of sulfamethoxazole (sulfonamides)
Inhibits PABA to DHF
65
What targets DNA topoisomerases
Fluoroquinolones and quinolones
66
MOA of nalidixic acid
Quinolone inhibits DNA topoisomerase
67
What are Streptogramins
Quinupristin and Dalfopristin: They inhibit 30S ribosome, used in treating vancomycin resistant s. aureus and vancomycin resistant enterococcus.
68
What are penicillin binding proteins
Transpeptidases
69
Penicillin bactericidal or bacteriostatic
Bactericidal (for gram-positive cocci and rods, gram-negative cocci, and spirochetes.
70
Penicillin G, V use
Gram positivies like pneumococcus, s. pyogenes, actinomyces, and meningococcus, and syphilis
71
Penicillin side effects
allergy, hemolytic anemia
72
Aminopenicillins susceptible bacteria
H. flu, e. coli, listeria, proteus, salmonella, shigella, enterococci.
73
Aminopenicillin mnemonic
ampicillin/amoxicillin HELPSS kill enterococci (H.flu, E. coli, Listeria, Proteus, Salm., Shig., enterococci
74
What are the penicillinase resistant penicillins
Oxacillin, nafcillin, dicloxacillin. They are narrow spectrum.
75
What makes penicillinase resistant penicillins resistant to penicillinase?
Bulky R group prevents access to beta-lactam ring
76
Side effects of oxacillin, etc. ?
Interstitial nephritis, hypersensitivity reactions
77
Antipseudomonals description
Extended spectrum: Pseudomonas and gram-negative rods, susceptible to penicillinase
78
What organisms are not typically covered by cephalosporins?
LAME: Listeria, Atypicals (Chlamydia, Mycoplasma), MRSA, and Enterococci.
79
Cephalosporins description
Less susceptible to penicillinases. Bactericidal
80
Name 1st gen. cephalosporins and targets
Cefazolin, cephalexin: PEcK; Proteus, E.coli, Klebsiella.
81
2nd gen cephs. and targets
Cefoxitin, cefaclor, cefuroxime: HEN PEcKS: H.flu, enterobacter aerogenes, Neisseria, Proteus, E. coli, Kleb, Serratia
82
3rd gen cephs. and targets
Ceftriaxone, cefotaxime, ceftazidime: serious gram-negative infections resistant to other beta-lactams:
83
Ceftriaxone for what infections specifically
Meningitis and gonorrhea
84
Ceftazidime indication
Pseudomonas
85
4th gen cephs. and targets
Cefepime: active against pseudomonas and gram-positives
86
5th gen cephs. and targets
Ceftaroline; broad gram-positive and gram-negative, including MRSA, no Pseudomonal coverage
87
Cephalosporin side effects
Vit. K deficiency, low cross-reactivity with penicillins, increases nephrotoxicity of aminoglycosides.
88
Monobactams MOA
Aztreonam: resistant to beta-lactamases, binds penicillin-binding protein 3. Synergistic with aminoglycosides. No cross-allerginicity with penicillins.
89
Aztreonam clinical use
Gram-negative rods only: no activity against gram-positives or anaerobes. Penicillin-allergy patients and renal insufficiency who can't tolerate aminoglycosides
90
Aztreonam side effects
Usually nontoxic; occasional GI upset
91
Carbapenems examples
Imipenem, meropenem, ertapenem, doripenem
92
Imipenem MOA
Borad-spectrum, beta-lactamase resistant carbapenem. Always give with cilastatin (inhibitor of renal dehydropeptidase I) to decrease inactivation of drug in renal tubules. "with imipenem, the kill is lastin with cilastatin'
93
Ertapenem activity
Limited pseudomonal coverage
94
Carbapenems clinical use
Wide spectrum: Gram-positive cocci, gram-negative rods, and anerobes.
95
Carbapenem side effects
GI distress, skin rash, seizures at high plasma levels
96
Meropenem benefits
Decreased risk of seizures and stable to dehydropeptidase I
97
Vancomycin MOA
Inhibits cell wall peptidoglycan formation by binding D-ala D-ala portion of cell wall precursors. Bactericidal.
98
Vancomycin clinical use
Gram positives only: MRSA, enterococcus, C. diff
99
Vancomycin side effects
NOT trouble free: nephrotoxicity, ototoxicity, thrombophlebitis: red man syndrome (give benadryl to prevent)
100
Vancomycin resistant MOA
Turn D-ala D-ala to D-ala D-lac
101
Ribosomal antibiotic mnemonic
Buy AT 30, CCEL at 50. Aminoglycosides, Tetracyclines, Clindamycin, Chloramphenicol, Erythromycin (Macrolides), Linezolid
102
Are protein synthesis inhibitors bactericidal or bacteriostatic
All are bacteriostaic except for aminoglycosides that are bactericidal. linezolid is variable.
103
Linezolid MOA
Blocks ribosome formation
104
Aminoglycosides MOA
Binds to 30S, prevents initiation complex formation
105
Chloramphenicol MOA
Binds 50S, blocks peptidyl transferase
106
Macrolides and Clindamycin MOA
Bind 50S, blocks translocation
107
Tetracyclines MOA
Binds 30S, blocks A-site tRNA binding
108
Aminoglycosides examples
Gentamicin, neomycin, amikacin, tobramycin, streptomycin
109
Aminoglycosides MOA
block formation of initiation complex and cause misreading of mRNA, also blocks translocation. Require O2 for uptake; cannot be used against anaerobes
110
Aminoglycosides clinical use
Severe gram-negative rod infections. Synergistic with beta-lactams.
111
Neomycin use
For bowel surgery
112
Aminoglycosides toxicity
Nephrotoxicity (with cephalosporins), Neuromuscular blockade, Ototoxicity (especially with loop diuretics), Teratogen
113
Aminoglycosides resistant MOA
Bacterial transferase enzymes inactivate the drug by acetylation, phosphorylation, or adenylation
114
What is the integrase inhibitor for HIV
Raltegravir
