STDs Flashcards
HPV that causes cervical cancer
HPV 16, 18, 31, 33
HPV that causes genital warts
HPV 6, 11
E1 and E2 in HPV
virulence factors
E1: recognizes origin of replication in viral genome
E2: helps E1 get onto viral genome
E6 and E7 in HPV
virulence factors in oncogenic strains
E6: binds and inactivates p53, target for ubiquination
E7: binds and inactivates Rb, target for ubiquination
What type of cells does HPV infect and why
only stem cells in cervix
because HPV needs host DNA synthase
only stem cells enter S-phase to replicate
Function of E6 and E7 in oncogenic strains
inhibit p53 and Rb
allow cell to enter S-phase without being stopped by those proteins
allows for host DNA-synthase to be expressed, viral genome to be copied
Classification of
Neisseria gonorrhoeae
Gram - diplococcus oxidase + only glucose oxidizer N. gonorrhoeae
Major virulence factor in N. gonorrhoeae
specialized pili
- attachment to host
- antigenic variation: immune system evasion
How to grow N. gonorrhoeae
Thayer-Martin media
Young person with septic arthritis in single joint most commonly has this
N. gonorrhoeae
has bacteremic phase when may enter joint space at negative pressure
Complications of N. gonorrhoeae
septic arthritis
PID -> tubal scarring
neonatal conjunctivitis
spread to peritoneum and liver capsule in women
N. gonorhoeae spread to liver capsule name
Fitz-Hugh-Curtis syndrome
HPV classification
dsDNA virus group I circular genome icosahedra nucleocapsid non-enveloped papovaridae Papillomavirus
What causes syphilis
Treponema pallidum
How to identify syphilis on stain
Gram -
sprirochete
1˚ syphilis presentation
chancre
small, painless, hard, red bump at site of infection
occurs 9 days - 3 mo after infection
chancre breaks down to form shallow crater w/ firm margins
no systemic Sx
2˚ syphilis presentation
systemic Sx: fever, headache, sore throat, lymphadenopathy
red/brown rash all over body including palms and soles
may lose hair
3 wk - 6 mo after chancre heals, resolves in 2 wk
3˚ syphilis presentation
aortic aneurysm: vaso vasorum destruction
neurosyphilis: cord, CN, or brain
gumma formation
When is gumma formed
gumma formed in 3˚syphilis
painful, swollen syphilic tumor
usually benign
Microscopy of syphilis options
dark-field microscopy
wet mount may detect spirochetes
Ab titers in syphilis
anti-cardiolipin Ab
anti-treponemal Ab
indirect immunofluresence available
Tx of syphilis
penicillin
tetracycline or erythromycin if allergic
Which STD commonly causes purulent discharge from penis
gonorrhea
Quick test for HSV
Tzanck smear
look for multinuclated giant cells
What immune response is most important in HSV
cell-mediated immunity
Thymidine kinase and its importance in HSV
only present in α-herpes viruses
- phosphorylated acyclovir
- 2x phosphorlations by other enzymes
- incorporated into DNA
- chain terminator
Classification of HSV
DNA virus icosahedral nucleocapsid Class I: dsDNA herpesviridae simplex virus HSV-1 and HSV-2
Trichinoma vaginalis
presentation
yellow, foamy vaginal discharge
Clue cells are seen where
in bacterial vagninosis
Tx of trichomonas vaginalis
metronidazole
Identification of trichomonas vaginalis
pear-shaped protozoan
w/ 4 flagella + 1 undullating membrane
Candida infections are almost always __________
opportunistic
post-Abx, diabetic, etc
Tx of candida
topical or systemic azoles
Identification of candida on microscopy
pseudohyphae
