L39- Urogenital Infections II Flashcards
UTIs are mostly caused by (exogenous/endogenous) microbes
endogenous- mostly from urinary tract microbiota
list some major concerns of STIs beyond the actual infection
- some STIs like HSV2, Syphilis an inc risk of HIV acquisition
- reproductive health consequences: i) PID –> infertility, ii) gonococcal opthalmia of fetus from mother
- drug resistance, main gonorrhea
Trichomonas vaginalis microbial features
(sexually transmitted, fomite transmission possible)
- protozoa (parasite) –> no cyst form
- 4 flagella –> may lose it for ability to cross barriers
- short undulating membrane for motility
Trichomonas vaginalis:
- (1) commonly affected group
- (2) infection site in men
- (3) infection site in women
1- young, sexually active women (for asymp. and symp. disease)
2- urethra
3- vagina
Trichomonas vaginalis:
- (1) clinical presentations
- inc risk of (2)
1:
- asymptomatic
- genital inflammation = vulvovaginal trichomoniasis: fishy odor, green-white discharge, itching
2- HIV transmission
Trichomoniasis Dx:
- (1) first check
- (2) gold standard test
- (3) non-culture tests
- (4) other DDx
1- vaginal pH, >4.5 is suggestive of disease (+ BV, not candidiasis)
2- Culture: modified Modified Diamond’s Media –> add 10% NaCl (look for **motile trophozoites) + 10% KOH whiff test (fishy odor)
3- NAAT (amplified test), DNA probe (non-amplified test), gram-stain smear
4- candidiasis: yeasts and pseudohyphae
Urethritis, UTI male presentation
burning sensation, dysuria
Urethritis, UTI female presentation
frequency, urgency, dysuria
fever, chills
Urethritis, STI male presentation
hematuria. hematospermia, penile discharge
dysorgasmia, itching, tenderness, penile swelling
lymphadenopathy
Urethritis, STI female presentation
vaginal discharge, itching
pelvic / abdominal pain, dyspareunia, stomach pain
Neisseria gonorrhea microbial features
- Gram- diplococci
- non-motile
- fastidious growth
- oxidase+
- multiple outer surface Ags
- sexual transmission, inc risk of HIV infection
reservoirs: only humans, rare fomite transmission
list results of all N. gonorrhea infections
1a) oropharyngeal infection –> pharyngitis –> 1% systemic spread (arthritis, endocarditis, meningitis)
1b) anal / genital infection –> local irritation w/ discharge OR asymptomatic (*women) —> 1% systemic spread
2) cervical infection (+/- Sxs) –> ascending infection –> uterine cavity, fallopian tube (PID, infertility, ectopic pregancy)
3) surface colonization during birth –> eye infection –> blindness or conjunctivitis
Gonorrhea male and female presentation
Men (95% symptomatic)
- mainly restricted to urethra
- purulent discharge: yellowish pus
- dysuria
Women -cervix infection -dysuria -vaginal discharge -abdominal pain (*inc risk of dissemination b/c more asymptomatic)
describe the risk of gonorrhea infections in women (hint- 2)
-more likely asymptomatic (Sxs in 95% males) –> inc risk of dissemination
(+ inc risk HIV transmission)
-vertical transmission during birth => eye infection (blindness or conjunctivitis)
list the attachment factors for N. gonorrhea
-pili: unusual, specialized mechanism of Ag variation by DNA rearrangement
- Opa (opacity protein)
- por protein (creates pore for nutrient extraction)
- Fe-binding proteins
- lipooligosaccharide (LOS)- induces TNFα
N. gonorrhea:
- attachment factors bind to (1), using (2) as the anchor
- replication occurs in (3) manner (include main resulting Sx)
1- columnar epithelial cells of distal urethra (males) or cervix (females)
2- pili + outer surface proteins
3- in situ –> large numbers in virulent cells –> shed in secretions (men + women)
N. gonorrhea:
- spread of infection occurs as (1)
- dissemination in to blood is common in (2) patients
- (3) is the result of chronic infection (men and women)
1: (Note- nonmotile, no flagella)
- males limited to urethra
- females –> as far as fallopian tube migration via urethral/uterine contractions
2- defective complement
3- scarring and stricture of fallopian tube or urethra
N. gonorrhea Dx:
- (1) first properties tested for
- (2) next non-culture lab tests
- (3) describe culture (describe agar)
1- pus sample –> smear -> intracellular Gram- diplococci
2- NAATs- PCR (amplified test) or DNA probe (non-amplified test)
3- Thayer-Martin: chocolate agar w/ vancomycin, colistin, nystatin) –> oxidase+ colonies
Chlamydia Trachomatis virulence factors
Atypical bacterium:
- Gram-
- EB infectious form, RB replicative form
- small obligate intracellular parasites
- entry via abrasions / lacerations
- may increase HIV transmission
list the clinical presentations of C. trachomatis by serotype
A,B,Ba,C –> trachoma
D-K –> conjunctivitis, infant pneumonia, urogenital disease
LGV-1,2,3 –> lymphogranuloma venerum
Chlamydia trachomatis clinical presentations
-usually no Sxs
Sxs: vaginal discharge, dysuria (burning- direct cell destruction, host inflammatory response)
- ~40% women –> PID = infertility, ectopic pregnancy, chronic pelvic pain
- uncommon male complications –> epididymitis, urethritis
Chlamydia pathogenesis mainly involves the presence of (1) on (2) cells
1- EB receptors (epithelial cells)
2- mucous membranes urethra, endocervix, endometrium, fallopian tubes, anorectum, respiratory tract, conjunctiva
Note- no long lasting immunity post-infection
Chlamydia Dx
NAATs- most sensitive method, urine sample (some for vaginal swab)
specimens: urine/urethra males, endocervix/female females, rectum, oropharynx
describe distribution of genital ulcers based on geographic locations
USA: i) HSV2 ii) syphilis (Treponema pallidum) iii) chancroid (hemophilus ducreyi) [iv) LGV / lymphogranuloma venereum- chlamydia trachomatis]
India, West Indies, Africa, S. America:
-Klebsiella granulomatis –> donovanosis / granuloma inguinale
describe genital ulcers based on characteristics:
- (1) number
- (2) tenderness
1:
HSV- clusters
Syphilis- 1-2
others: 1
2:
Tender: HSV, chancroid, 1/3 syphilis
Painless: LGV, Donovanosis
describe adenopathy of genital ulcers:
- (1) HSV
- (2) syphilis
- (3) chancroid
- (4) LGV
- (5) donovanosis
1- inguinal, very tender 2- rubbery, mildly tender 3- inguinal, fluctuant, very tender 4- fluctuant, 'groove sign' 5- firm, mimics LGV
HSV1/2 viral features
large enveloped dsDNA icosahedral
Note- highest spread during outbreaks, but there is spread between outbreaks
HSV1/2- 1st episode, primary -(1) lesions / Sxs (at presentation) -(+/-) HSV-1 Ab -(+/-) HSV-2 Ab
1- lesions present, severe, bilateral
2- neg.
3- neg.
HSV2- 1st episode, non-primary -(1) lesions / Sxs (at presentation) -(+/-) HSV-1 Ab -(+/-) HSV-2 Ab
1- lesions present, moderate
2- pos.
3- neg.
HSV2- 1st episode, recurrence -(1) lesions / Sxs (at presentation) -(+/-) HSV-1 Ab -(+/-) HSV-2 Ab
1- lesions present, mild
2- pos. or neg.
3- pos.
HSV2- symptomatic, recurrence -(1) lesions / Sxs (at presentation) -(+/-) HSV-1 Ab -(+/-) HSV-2 Ab
1- lesions present, mild, unilateral
2- pos. or neg.
3- pos.
HSV2- asymptomatic infection -(1) lesions / Sxs (at presentation) -(+/-) HSV-1 Ab -(+/-) HSV-2 Ab
1- no lesions present, no Sxs
2- pos. or neg.
3- pos.
describe the cells HSV invades and the types of infections
Lytic: most cells- Cowdry type A inclusion bodies, syncytia
Persistent: lymphocytes, macrophages
Latent: neurons
(1) HSV mechanism to evade immune system
(2) recurrence triggers and severity
1- blocks IFN effects, prevents Tc/CD8+ recognition of infected cells, escapes Ig neutralization by latent (neuron) infection
2- stress usually, but triggers poorly understood –> episodes dec in severity
HSV Dx:
- (1) sample
- (2) testing during outbreak
- (3) testing between outbreaks
1- ulcers
2- PCR, cell culture, serology tests (glycoprotein G)
3- Ab testing
Treponema pallidum microbial features
- thin, tightly coiled
- **spirochetes
- motile, endoflagellum
- slow replication
- obligate human pathogen
- unusual outer membrane (no LPS, no porins)
- inc likelihood of HIV transmission
describe presentation and time course of primary Syphilis
(treponema pallidum)
- 9-90 days post-infection
- hard, painless ulcer –> thin, greyish crust
- disappears 1wk after proper Tx
- disappears 4-12 wks w/o Tx
- 75% untreated infections do not progress
describe presentation and time course of secondary Syphilis
(treponema pallidum)
- 2-8 wks after ulcer (primary)
- flu-like syndrome
- 80% generalized maculopapular rash (copper color) + multiple Sxs indicative of systemic infection
- condylomata lata lesions (swarming with organism): wet mucous patches, contagious
describe presentation and time course of tertiary Syphilis
(treponema pallidum)
- 15-20 yrs post-infection
- diffuse chronic inflammation
- neurosyphilis => dementia, meningitis, hallucinations
- CVS: aortic aneurysm
- Gummatous: hypersensitive granulomatous reaction (destructive to viscera or mucocutaneous areas)
