microbiology Flashcards
some different types of bacteria causing STI’s
- GC
- chlamydia - lymphogranuloma venereum
- mycoplasma
- ureaplasma
- syphilis
- anaerobes
what is the typical age range of people being affected by GC?
- 15-49 years old
what type of bacteria is GC?
- gram negative diplococci
- and is sexually transmitted
how do you screen for GC?
- PCR
- requires chocolate agar to grow
- specific GC media
what bacteria is show on this microscopic image?
GC
what does GC cause?
- urithritis, cervicitis, disseminated disease, PID, pharyngitis, proctits
antibiotic treatment for GC depends on local resistance? true or false?
- true
- usually ceftriaxone, not ciprofloxacin unless sensitivity is known
- azithromycin
what kind of infection makes antibiotic tx for diseases like GC less successful?
- infections of the pharynx due to limited tissue penetration of antibiotics
chlaymdia trachomatis is what kind of bacteria?
- intracellular bacterium
which gender is chlamydia more common in?
- women, 15-24 years old
how is chlamydia transmitted?
- sexually transmitted
-> often 50% of infection resolves untreated after 12 months
what is a typical symptom presentation of chlamydia?
- increased vaginal discharge, post-coital bleeding, dysuria, dyspareunia, rectal pain
what are some complications of chlamydia?
- PID, salpingitis, endometritis, tubal infertility, ectopic pregancy, perihepatitis, reactive arthritis
what is typical testing for chlamydia?
- NAAT
what is the tx for chlamydia?
- doxycycline or azithromycin
-> also covered by ofloxacin
you do not need to use contact tracting for chlaymdia true or false?
- false
- you do
serovar L2 (and L1/L3) are specific strains that cause?
- lymphogranuloma venereum
how does lymphogranuloma venereum present?
- presents as outbreaks
what is the clinical presentation of lymphogranuloma venereum?
- painless ulcers and/or haemorrhagic proctitis, pharyngitis, lymphadenopathy (often unilateral)
what are some anaerobes that can cause bacterial vaginosis?
- gardnerella vaginalis
- prevotells sp.
- mobiluncus sp.
- atopobium sp..
what is the testing for bv?
- gram stain
what is the tx for bv?
- metrondiazole (oral or gel), clindamycin cream
and avoid vaginal douching
can you do gram stain testing on mycoplasma genitalium? and if no, why not?
- you can’t do gram straining on this anaerobe as it lacks cell walls
- NAAT testing instead…
is mycoplasma genitalium sexually transmitted? true or false?
- true
- usually asymptomatic carriage
how does mycoplasma genitalium present?
- PID, and urethritis
what is the tx for mycoplasma genitalium?
- doxycycline or moxifloxacin
-> increasing macrolide resistance
what is ureaplasma?
- sexually transmitted disease
- which can become part of normal genital flora
what does ureaplasma cause?
- urethritis, epididymitis, and prostatitis
how is ureaplasma found?
- PCR
what kind of sensitivity testing can be carried out for ureaplasma?
- liquid culture
what kind of bacteria is treponema pallidum?
- spirochaete, moved by rapid rotation
what does treponema pallidum cause?
- causes syphilis
how is treponema pallidum transmitted?
- sexually transmitted, via blood transfusion or during pregnancy
how is treponema pallidum tested for?
- PCR from lesion sample
and treponemal serology
test 1: treponemal IgG and IgM
test 2 if test 1 is positive: specific treponema pallidum assay and RPR (rapid plasma reagin)/VDRL
primary: how does treponema pallidum present?
- chancre (genital ulcer) resolves over 3-8 weeks
secondary: in 25% of untreated primary treponema pallidum:
- rash including palms and soles
- mucous pathes
- condylomata lata
- hepaitits, splenomegly, glomerulonephritis
at what point does latent treponema pallidum disease present?
- 3-12 weeks
what is a late (tertiary) disease presentation of treponema pallidum?
- neurosyphilis/cardivascular/gummatous
can treponema pallidum be acquired congenitally true or false?
- true
what is tx for treponema pallidum?
- benzathine penicillin
or pen relatives, or doxycycline, or azithromycin or erythromycin
what are the 2 types of herpes simplex?
- HSV-1
- HSV-2
they are DNA viruses
how is HSV1 transmitted?
- oral-to-oral contact
- ‘cold sores’
how is HSV-2 transmitted?
- sexually transmitted
- i.e. genital herpes w lesions
is HSV an asymptomatic or symptomatic virus?
- typically asympomatic
what are the complications for herpes simplex?
- increases risk of HIV transmission by 3x
- more severe disease in immunocompromised people
specific to HSV-1 what is a complication of this infection?
- keratitis, encephalitis
specific to HSV-2 what is a complication of this infection?
- meningoenecephalitis
what is neonatal herpes?
- affects 10/100,000 births globally
- primary herpes in mother late in pregnancy
herpes simplex tx?
- aciclovir and valaciclovir
- prevention is key
what kind of virus is HPV
- small, non-enveloped DNA virus
- highly transmissable
- transmitted sexually
what kind of cancers is HPV assoc with?
- cervical cancer
- assoc w further anogenital and head and neck cancer types
HPV 16 + 18 can cause what kind of cancer?
- cervical cancer
HPV 6 and 11 causes what disease?
- genital warts
is varicella zoster sextually transmitted infection?
- no
- highly contagious passed via droplets and aerosols
what kind of testing is required to differentiate between HSV and varicella zoster?
PCR testing
how does varicella zoster first present?
- chickenpox in children <10
- then zoster (more common in people over 50 and immunocompromised)
what is a complication of primary infection of varicella zoster?
- pneumonia
- encephaltiis
- pregnancy: fetal injury
what are some complications of recurrent VZ infection?
- lasting nerve damage
- visual impairment
what is tx for severe cases of VZ?
- aciclovir
- vaccination available - attenuated ‘live’ vaccine
what is yeast?
- gram positive fungi
- present on normal skin flora
what type of yeast most commonly shows up on a germ tube pos test?
- candida albicans (mostly) sometimes pseudohyphae on microscopy
what is a common clinical appearance of a yeast infection?
- vulvovaginal cadidiasis
what is the tx for yeast infection?
- topical and/or systemic antifungals
what is trichomonas vaginalis?
- unicellular protozoa
- sexually transmmitted
- more common in women
how does trichomonas vaginalis present?
- clinically
- discharge w vulval itching, dysuria, prostatitis, ?preterm delivery
testing for tricho?
- microscopy from vaginal swab
- NAAT also from urine
tx for tricho?
- metronidazole
