Micro Flashcards
Normal vaginal flora
Lactobacillus spp. which produces lactic acid, hydrogen peroxide which suppress growth of other bacteria
strep viridian’s, group B beta haemolytic strep, candida sep
normal pH of vagina
acidic
non sexually transmitted genital tract infection
candida infection (thrush)
bacterial vaginosis - more common in sexually active people but not sexually transmitted
prostatitis - can also be associated with sexually transmitted infections
candida infection - is it normal to be have candida
predisposing factors
30% woman have candida and are fine
recent AB therapy, high oestrogen levels, poorly controlled DM, immunocompromised px
candida presentation
dx
rx
intensely itchy white vaginal discharge - discharge looks like cottage cheese
clinical diagnosis - high vaginal swabs for culture - was into the posterior of the cervix
topical clotrimazole pessary or cream, oral fluconazole
microscopy of candida albicans
fungus
yeast with hyphae (budding)
how does an infection of Candida look like in males
spotty rash of candida balanitis
settles with cream
common in males with poorly controlled DM
bacterial vaginosis organisms
symptoms
dx
why is it distressing
Gardnerella vaginalis/mobiluncus sp. /other organisms incl anaeorbes
thin watery fishy smelling discharge
clinical dx raised vagina pH >4.5
people will try wash the vagina out which will worsen the imbalance and the smell
lab testing for BV
treatment
HVS sent to lab and examined miscroscopically to look for clue cells - high subjective test. Hay - Son scoring system estimates proportions of clue cells to epithelial cells and lactobacillus
PO metro
prostatitis classification
acute bacterial
chronic bacterial
chronic/chronic pelvic pain syndrome
acute bacterial syx what can it be a cx of organisms dx rx
symptoms of UTI but may have lower abd pain/back/perineal/penile pain and tender prostate on examination
rare cx of UTI in men
E.Coli and other coliforms, check for STI in <35s gonorrhoea, chlamydia
clinical signs and MSSU for C&S. STI suspected then first pass urine
cipro for 28 days, if high C Diff risk then Trimethoprim for 28 days
bacterial STIs
viral
parasites
chlamydia trachoma’s
neirssera gonorrhoea
treponema pallidum (syphilis)
HPV (genital warts)
herpes simplex (herpes)
hep and HIV
trichomonas vaginalis
phthirus pubis
scabies
chlamydia what does it infect who how gram stain groupings rx
commonest bacterial STI in the UK
urethra, rectum, throat and eyes and endocervix in females
biggest poor in males who have sex with other males
obligate intracellular bacteria with biphasic life cycle - does not reproduce outside a host cell
does not stain with a gram stain as there is no peptidoglycan in the cell wall
serovars A-C = trachoma eye infection (not an STI)
servers D-K - genital infection - commonest STI
Servers L1-L3 - lymphogranuloma vnerum - can mimic IB S
azithomycin 1g PO for uncx chlamydia
gonorrhoea more common that chlamydia? infects what? gram stain? what about the organism
less common
urethra, rectum, throat and eyes and endocervix in females
gram neg diplococcus - looks like two kidney beans facing each other, easily phagocytksed by polymorphs so often appear intracellularly on a gram film
fastidious organism that does not survive well in less than ideal conditions so outside the body
discharge from a gonorrhoea infection
purulant discharge - dripping tap
dx of chlamydia and gonorrhoea
combined nucleic acid amplification tests or PCR-test for both organisms in one test
who are the tests for both done on
male - first pass urine sample
females - HVS or vulvo vaginal swab
rectal and swabs
eye swabs for babies and adults - babies for when the mothers have gonorrhoea as eyes can be full of pus
what other tests can be for for gonorrhoea
microscopy of urethral/endocervical swabs
culture on selective agar plates - done on endocervical, rectal and throat swabs but not on vaginal swabs
advantages of PCR/NAATs over culture
disadvantages
less invasive
more sensative
will be positive even if organisms die
takes hours not days
cannot test AB sensitivities without culture
will detect dead organisms - have to wait 5 weeks to do a test of cure tests
AB resistance in N. gonorrhoea
what are they resistant to
recommended treatment
what is recommended for all px
resistant to pencillins, tetracyclines, quinolone and oral cephalosporins
IM ceftriaxone and oral azithromycin
test of cure
syphilis caused by what
gram stain
tests
treponema pallidum
does not stain with gram stain
cannot be grown in artificial culture media so dx PCR or blood test to detect antibodies
stages of syphilis
1 - organism multiplies at inoculation site and gets into the blog stream - chancre can heal without treatment
2 - large numbers of bacteria circulating in the blood with manifestations at different sites (snail track ulcers, rash, flu like)
Latent stage - no symptoms but low level multiplication of spirochete in intima of small blood vessels. can be early and late latent stages
late stage - cardiovascular or neurovascular cx years later
syphilis dx
dark ground microscopy to look for spirochetes in exudate from 1 and 2 lesions
swab of 1 and 2 lesions for PCR
serology - test for antibodies non specific and specific
non specific tests
VDRL
RPP
indicate tissue inflammation may be falsely positive how active the disease is useful for monitoring response to therapy usually become negative after treatment
specific serological tests
IgM and IgG ELISA used as the screening test for syphilis then the following tests can be done if +ve
TPPA
TPHA
specific for syphilis but remain positive for life
not useful for monitoring response in therapy
syphilis treatment
injectable long acting preparations of penicillin provided px not penicillin allergic
genital warts cause organism tests types
commonest viral STI
HPV
non enveloped icocohedral virus containing double stranded DNA
cannot be grown in culture media or maintained in lab animals so difficult to study
>100 types 6 and 11 - genital warts
16 and 18 cervical cancer
genital warts spread dx recur vaccine
spread by close genital skin contact
clinical dx
cryotherapy, podophyllotoxin cream/lotion
often re occur
11-13 yo girls that immunise against 6,11,16 and 18
genital herpes cause
organism
transmission
spread
HSV 1 and 2
enveloped virus containing double stranded DNA
transmitted by close contact with someone shedding the virus
spread by either genital/genital or oropharyngeal/genital contact
genital herpes pathogenesis
primary infection
virus replication
primary infection may be asymp
replicates in dermis and epidermis
gets into sensory nerve ending to sensory and autonomic nerves
inflammation at nerve endings - painful multiple small vesicles which are easily deroofed
virus migrates to sacral root ganglion and hides there
can be reactivated causing recurrent genital herpes attack
intermittent virus shedding can occur in the absence of symptoms
GH dx and rx
what does it look like
swab in viral transport medium
acyclovir and pain relief
shallow ulcers - very painful
trichomonas vaginalis micro transmission causes what dx rx
single cell protozoal parasite - divided by binary fission - human host only
transmitted by sexual contact
vaginal discharge and irritation in females (urethritis in males)
high vaginal swab for microscopy
oral metro
pubic lice - phthirus pubis
how is it acquired
how long do they live for
treatment
close genital skin contact
males live for 22 days and females for 17
malathion lotion
