Micro: Things I don't know Flashcards
1
Q
HPV
- genome
- capsid
- envelope
A
- small circular dsDNA
- icosahedral capsid: self assemble
- non-enveloped: contributes stability of virus on skin and fomites
2
Q
L1
A
protein capsid of HPV used for vaccine
3
Q
laryngeal papilloma
A
HPV 6 and 11
infants/young children
benign warts in respiratory tract
complication: respiratory distress leading to death
Tx: multiple surgeries
prevention: remove genital warts in pregnancy
4
Q
epidermodysplasia verruciformis
A
HPV infection in someone with inherited defect in cellular immunity
warts on face, trunk, limbs throughout life and non-metastatic tumors
5
Q
HPV genital warts
A
condyloma acuminata
condyloma plana
6
Q
SPI
A
subclinical papilloma infection
HPV infection that can lead to CA
7
Q
5% acetic acid
A
HPV
brush on infected area to detect SPI: turns warts white
reveals dysplasia: use to take colposcopy
8
Q
pap smear
A
HPV
detects koilocytotic squamous epithelial cells
9
Q
cofactors in the development of cervical cancer in women with HPV
A
smoking
co-infection with herpes simplex
10
Q
Dx of HPV
A
CANNOT be grown in cell culture
- clinical appearance
- abnormal Pap, colposcopy to look for dysplasia
- HPV DNA detection test
11
Q
Tx of HPV: methods for removal
A
remove warts (does NOT eradicate virus so can return)
- BCA, TCA
- cryotherapy
- LEEP
- podofilox
- imiquimod
- intralesional IFN injections
12
Q
BCA: bichloroacetic acid
TCA: trichloroacetic acid
A
brush on warts: denatures proteins
Tx: HPV
AE: irritated/burned surrounding skin
13
Q
cryotherapy
A
liquid nitrogen to physically disrupt wart (be careful not to freeze to deep: causes scarring)
Tx: HPV
14
Q
LEEP (loop electrosurgical excision procedure)
A
removes dysplastic cervical cells
Tx: HPV
15
Q
HSV
- genome
- capsid
- envelope
A
- large: dsDNA (has viral DNA pol)
- icosohedral
- yes
16
Q
Where does HSV reside in latency?
- HSV 1
- HSV 2
A
peripheral sensory neurons: maintained EXTRACHROMOSOMALLY
- trigeminal ganglia
- sacral ganglia
17
Q
HSV replication cycle
A
- viral attachement
- pH-independent plasma membrane fusion
- release of nucleocapsid that migrates to the nucleus
- genome is released
- IMMEDIATE EARLY transcription/translation: makes transcriptional regulators to modify host RNA pol
- production of EARLY PROTEINS: replicate viral genome: include viral THYMIDINE KINASE and viral DNA POL
7: LATE PROTEINS: capsomeres, envelope, STRUCTURAL proteins - virus assembly in NUCLEUS (NUCLEAR INCLUSIONS)
- virus buds from plasma membrane
18
Q
syncitia
A
HSV
infected cells fuse with adjacent non-infected cells to form giant cells with more than one nucleus
Mechanism: viral glycoproteins are also present on plasma membrane of infected cells late in infection
19
Q
Dx of HSV
A
Tzanck smear
20
Q
Tzanck smear
A
HSV
cells from ulcerous lesion reveal multinucleated giant cells with nuclear inclusion bodies
21
Q
LAT (latency-associated transcript)
A
HSV
only gene expressed in latency
prevents apoptosis of infected neuron
22
Q
What causes HSV to reactivate?
What effect does this have?
A
decline in cell mediated immunity
kills infected neuron and recurrent epithelial infection occurs
23
Q
HSV 1 diseases
A
- gingivostomatitis
- herpes labialis (FEVER BLISTER)
- herpetic whitlow (finger vesicle)
- KERATITIS
- conjunctivitis
- blepharitis
- ENCEPHALITIS
24
Q
HSV 2 diseases
A
- CERVICITIS
- VULVAR VESICLES
- vaginal vesicles
- urethritis
- PENILE VESICLES
- perianal vesicles
- MENINGITIS
- encephalitis
25
gingivostomatitis
PRIMARY HSV
vesicles on lips, tongue, facial skin around mouth
FEVER, HEADACHE
26
fever blister
RECURRENT HSV
vesicles in some of the same sites as primary after stress
FEVER, HEADACHE
27
How do you determine primary from recurrent HSV genital vesicles?
Sx of both?
difficult; Hx
| recurrent: fewer lesions that heal more quickly; more frequent soon after primary infection (diminishes over time)
28
genital HSV Sx
1. vesicles (penis, external/internal vagina; can cause urethritis, cervicitis, vaginitis)
2. flu like
3 itching, buringin in infected area
4. muscle aches of legs, buttocks
29
prodrome symtoms
Sx that can tip HSV sufferer of an impending recurrent infection
30
Can you get HSV if partner doesn't have vesicles?
yes
| virus sheds in absence of recurrent vesicles ant after lesions are unapparent
31
HSV blepharitis, conjunctivitis
PRIMARY ocular HSV infection
CHILDREN
Sx: small vesicles/pustules around eye lid
32
HSV keratitis
SECONDARY ocular HSV infection
Sx: red painful eye, blurred vision, photophobia
if untreated: corneal scarring
33
HSV encephalitis
```
RARE (not more common in immune compromised)
adults: recurrent HSV1
neonates: primary HSV2
Sx: headache, fever, CONFUSION, SEIZURES
high MORTALITY
```
34
HSV meningitis
PRIMARY HSV2
Sx: headache, STIFF NECK, vomiting
usually resolves
35
Neonatal HSV
1st/2nd week postpartum
best outcome: infection limited to SKIN, MOUTH, EYES
severe: most DIE or have significant sequelae
1. ENCEPHALITIS: SEIZURE, IRRITABILITY, COMA
2. disseminated: organ failure (check liver enzymes)
36
When do neonates get infected with HSV?
What is the chance of transmission if mother is undergoing a primary vs. secondary infection?
What precautions should be taken to prevent transmission from mother to infant?
most: DELIVERY
5%: transplacental
primary: 30%
secondary: 2-3% (maternal Ab are protective)
C-section if herpatic lesions are present
37
```
Dx of HSV
1-4: general
5: keratitis
6: meningitis
7: encephalitis
8: neonatal
```
1. PCR of vesicles (most important)
2. culture (7-10 days): CYTOPATHIC EFFECT (CPE); old gold standard
3. serology (only indicates past infection unless Ig-type specific)
4. TZANCK smear
5. keratitis: slit lamp examination
6. meningitis (aimed at ruling out bacterial origin): CSF used for PCR/culture
7. encephalitis: PCR/SOUTHERN BLOT (normal EEG rules out HSV as cause)
8. neonatal: check liver enzymes for disseminated disease
38
HSV Tx
NO cure
1. ACYCLOVIR
2. vidarabine, trifluorodine
3. FOSCARNET
4. DOCOSANOL
39
foscarnet
MOA: pyrophosphate analog: blocks viral DNA pol
NO phosphorylation required
Tx: HSV when ACV fails
40
docosanol
OTC for cold sores
MOA: moodiness host cell membrane so virus envelope cannot fuse with PM
Tx: oral HSV
41
vidarabine, trifluorodine
eye drops
MOA: inhibit DNA pol
Tx: HSV keratitis
42
When do you give oral vs. IV acyclovir?
Tx: HSV
oral: genital outbreak/prevention
IV: encephalitis, neonatal
43
Treponema pallidum
1. disease
2. type of microbe
3. source of antigen for serological test
4. pathology
1. syphilis
2. motile spirochete: thin peptidoglycan with inner/outer membrane (outer has mostly lipoproteins and lipids rather than LPS)
3. rabbit testes
4. host cellular inflammatory response (also humoral response that is not able to eliminate infection); LATENCY
44
primary syphilis
PAINLESS hard CHANCRE at site of entry
| non-tender INGUINAL LYMPHADENOPATHY
45
secondary syphilis
1-2 months later
systemic: disseminated
Sx: fever, headache, non-tender DIFFUSE SWOLLEN NODES, mouth and genital lesions (SNAIL TRACK), RASH that eventually includes SOLES and PALMS and/or wart lesions (CONDYLOMATA LATA) on perineum/anal region
may have ALOPECIA, MILD MENINGITIS, liver involvement
46
tertiary syphilis
```
ENDARTERITIS
almost any organ system
1. CV: AORTIC VALVE REGRUGITATION
2. skin/bone: GUMMA
3. CNS: meningitis (asymptomatic or acute syphilitic), meningovascular (can infarct cerebral vessels), paresis (many spirochetes in cerebral cortex/meninges: personality changes, INSANITY, paranoia), TABES DORSALIS (demylization of posterior columns/dorsal roots): SHUFFLES when walking, lightening pains
patient is NOT infectious
few spirochetes detected in lesions
```
47
syphilis Dx
1. serology: RPR, VDRL, FTA--ABS
2. dark field microscopy of chancre
CANNOT: culture
48
Syphilis Tx
PENICILLIN: Pen G
pregnant women: desensitize her and give PENICILLIN)
ALT (resistance): macrolides, azithromycin
49
congenital syphilis
can have still birth or spontaneous abortion; may have symptoms at birth, may develop years later
1. disseminated infection
2. late congenital syphilis
50
early latent syphilis
1. Sx
2. serology
3. relapse?
4. infectious?
1-2 yr period after secondary infection
1. no
2. positive
3. may relapse to secondary syphilis
4. pregnant woman may pass infection in utero
51
late latent syphilis
1. Sx
2. serology
3. relapse?
4. infectious?
follows early latent syphilis: 1-2 years post infection and may last lifetime
1. no
2. positive
3. no
4. not infectious even to fetus
52
disseminated congenital syphilis
transmitted transplacentally after 1st trimester via blood
| Sx: SNUFFLES, SNAIL TRACK lesions, CONDYLOMA LATA, HEPATOSPLENOMEGALY, BULLOUS RASH
53
late congenital syphilis
develops over years: starts around age 2
Sx: bone abnormalities (frontal bossing, SABER SHINS), vision defects (GUN BARREL SIGHT), HUTCHINSON'S TRIAD (notched incisors, keratitis, deaf)
54
rapid plasma reagin (RPR) test
syphilis: SENSITIVE
antigen: cardiolipin
mix serum with cardiolipin: look for agglutination (pos. test)
decreases with Tx (can see antibiotic efficacy)
55
fluorescent treponemal antigen-absorbed (FTA-ABS) test
syphilis: SPECIFIC
antigen: pathogenic T. pallidum
1. Pt. serum is mixed with non-pathogenci treponemes to remove cross reacting Abs against normal spirochete flora
2. mix serum with T. pallidum fixed on slide
3. add fluorescent dye tagged with goat-antihuman Ig
4. positive: fluorescent staining spirochetes using fluorescence microscope in dark
stays elevated after Tx
56
general disease research laboratory (VDRL) test
syphilis
antigen: cardiolipin
cheap and sensitive serology test
57
Haemophilis ducreyi
PAINFUL SOFT CHANCRE
| ragged, raised
58
Chlamydia trachomatis (Ct)
1. microbe type
2. forms
3. virulence
1. obligate INTRACELLULAR G (-) parasite
2. two forms: EB, RB
3. intracellular, causes INFLAMMATION (HSP)
59
Neiserria gonorrhoeae (gonococcs, GC)
1. microbe type
2. pathology/virulence
1. NO capsule
| 2. LPS causes INFLAMMATION, PILI and outer membrane surface proteins (antigenic variation), IgA1ase
60
Ureaplasma urelyticum
mycoplasma: NO cell wall
| urethritis/cervicitis
61
Dx of Ct and GC
NAAT (nucleic acid amplification test) on urine or exudates
62
sequela for Ct and GC
PID
63
newborn infection of
1. Ct
2. GC
1. conjunctivitis, PNA
| 2. conjunctivitis (rare due to prophylaxis)
64
EB (elementary body)
C. trachomatis
| metabolically inert but infectious
65
RB (reticulate body)
C. trachomatis
| grows in membrane bound vacuole (inclusion body) in CYTOPLASM of MUCOSAL EPITHELIAL cells
66
pili
GC
attachement
antigenic variation: varying pilS insert into pilE
67
pilS
GC
vary
silent with no promoter
68
pilE
GC
| expression locus with promoter
69
GC, Ct lower genital tract infections
cervicitis, urethritis (GC can disseminate from this, Ct can't)
70
GC, Ct upper genital tract complications
1. SALPINGITIS, PID
2. epididymitis
3. perihepatitis (FITZ-HUGH-CURTIS: VIOLIN STRING adhesions of liver)
4. prostatitis (GC only?)
71
Other sites of: GC, Ct
1. rectal
2. conjunctivitis
3. Reiters' syndrome
GC only: PHARYNGITIS, DISSEMINATED
72
disseminated GC
SEPSIS with RASH, FEVER, SEPTIC ARTHRITIS
| also can have: endocarditis, meningitis
73
Reiters' syndrome
Ct mostly, occasionally GC
| reactive, non-septic arthritis (immune response related) following bacterial enterocolitis
74
Sx of urethritis in men
1. GC
2. Ct
3. both
need lab Dx to differentiate
1. purulent penile discharge
2. less purulent, milky discharge
3. DYSURIA, itching at distal urethra
75
Sx of cervicitis
GC, Ct
| dysuria, white discharge from endocervix
76
PID
1. organisms
2. organs effected
3. Sx
4. Tx
5. complications
1. GC, Ct, mycoplasma, Non-STD anaerobes
2. endometritis, salpingitis, tubo-ovarian abscess, pelvic peritonitis
3. Sx: lower abdominal pain (dull to severe), adnexal tenderness, cervical motion tenderness, fever, may have cervicitis or vaginal bleeding
4. Tx: DOXYCYLINE and CEFOXITIN
5. ectopic pregnancy, chronic pelvic pain
77
Ct: infant pneumonia
afebrile, STACCATO cough with TACHYPNEA
CXR: hyperinflation with bilateral infiltrates
eosinophilia, elevated IgM
conjunctivitis at same time suggests Ct
78
Dx of Ct
1. GOLD STANDARD: NAAT
2. gram stain: no cocci, PMNs (only accurate in males, not females)
3. culture in tissue rarely done
4. rapid antigen test
79
Dx of GC
1. gram stain: G- in PMNs (only accurate in males, not females)
2. GOLD STANDARD: THAYER-MARTIN medium for complicated infections: grows GC (antibiotics to get rid of other organisms); also gram stain, OXIDASE POS.
3. NAAT
4. rapid antigen test
80
Tx of GC
must treat for GC and Ct
IM CEFTRIAXONE and AZT (for Ct)
CANNOT give fluoroquinolone
81
Tx of Ct
AZITHROMYCIN
| ALT: doxycycline (CI in infant, children, pregnancy; 10 day regimen decreases compliance); erythromycin
82
How can you prevent GC in eyes of newborn?
silver/nitrate topical antibiotics
| does NOT work for Ct
83
lymphogranuloma venereum (LGV)
Ct: L1-3
Sx: SWOLLEN LYMPH NODES with suppuration, ULCER at site of entry
RARE in US
84
trachoma
non-STD Ct infection
can cause blindness
Asia, Middle East, Africa
85
Dx of vaginitis and vaginosis
microscopic
| rapid examination of discharge
86
candidiasis: candida albicans and C. glabrata
1. microbe type
2. discharge type
3. disease
MOST COMMON
1. fungus
2. scant, white, clumped
3. vaginitis
87
gardnerella vaginalis
1. microbe type
2. discharge type
3. disease
1. bacteria
2. GRAY, adherent (coats vagina); FISHY odor
3. bacterial vaginitis (BV)
88
mobiluncus spp.
1. microbe type
2. disease
1. bacteria
| 2. bacterial vaginitis (BV)
89
What is the key factor allowing overgrowth of Candida and bacterial vaginosis (BV)?
disturbance of normal flora that maintain low pH and produce H2O
ex: antibiotics, DM, sex, douching, initial use of IUD, menses, pregnancy, tight fitting undergarments
90
Trichomoniasis vaginalis
1. microbe type
2. discharge type
3. disease
1. single cell protozoan: FRANK PATHOGEN
2. profuse FROTHY YELLOW, FISHY odor
3. urethritis, vaginitis
91
Which microbe that causes vaginalis is sexually transmitted not part of the normal flora?
Trichomoniasis vaginalis
| reason it is a FRANK pathogen
92
bacterial vaginosis (BV)
NO single causative agent: caused by combination of anaerobes
93
Sx of vaginosis
```
VAGINAL DISCHARGE (malodorous for BV)
dysuria, itching (in Trichomonal or candidiasis; not mentioned for BV)
```
94
cystitis Sx
dysuria, suprapubic pain, leukocytes in urine, significant bacteria in urine
95
pyelonephritis Sx
cystitis Sx
PLUS: FEVER, FLANK PAIn
CASTS in urine
96
Dx of bacterial vaginosis (BV)
1. odor
2. discharge
3. pH
4. micro
5. Sx
6. inflammation
1. whiff test: FOUL odor after KOH addition (FISHY)
2. dirty white or GRAY (homogeneously coats vaginal wall)
3. above 4.5
4. CLUE cells
5. NO dysuria or vaginal discomfort
6. no
97
Dx of candidiasis vaginosis
1. pungent but not foul
2. COTTAGE CHEESE (white and clumped)
3. 4.5 or below (normal)
4. KOH: BRANCHING HYPHAE
5. extreme ITCHING, dysuria
6. leukocytes
98
Dx of Trichomonas vaginosis
1. whiff test: may be malodorous
2. FROTHY YELLOW(GREEN)
3. above 4.5
4. TWITCHING TRICHOMONADS (size of PMNs); PMNs
5. itching, dysuria
6. leukocytes
STRAWBERRY CERVIX
99
Tx of Trichomonal vaginitis
oral metronidazole
| Tx partner too
100
Tx of BV
oral metronidazole for 7 days
101
Tx of vaginal candidiasis
topical and oral azoles
