GU infections Flashcards
Which is the best specimen to send to the Microbiology Lab to screen for sexually transmitted infections in a 20 year old asymptomatic female who attends her GP Practice?
A vulvovaginal swab for chlamydia/gonococcal PCR
Metronidazole is the treatment of choice for which two infections?
Bacterial vaginosis and Trichomons vaginalis
Metronidazole is useful for treating anaerobic infections (BV) and protozoal infections (TV)
Serotypes L1,L2 &L3 are associated with Lymphogranuloma Venereum infection in MSM
True
Clue cells are suggestive of which infection
Bacterial vaginosis
The increase in antimicrobial resistance has resulted in a test of cure being advised for all patients with gonorrhoea.
True
Describe the features Neisseria gonorrhoeae
Gram negative diplococci (two kidney beans facing each other)
Describe the gram stain of Chalmydia?
Does NOT stain with Gram stain (no peptidoglycan in the cell wall)
Behaves like a gram negative stain.
What shape is chlamydia?
coccobacilli
Describe the lifecycle of chlamydia trachomatis
Obligate intracellaular bacteria with biphasic lifecycle.
- ‘Elementary body’ firs hase, infects host nucleus.
- ‘Reticulate cell’ multiplies inside host cell & results in cell lysis
chlamydia trachomatis CANNOT reproduce outside host cell
True
Why does Neisseria gonorrhoeae often APPEAR to be intracellular on a gram film?
Because it is easily phagocytosed by polymorphs - this is related to its purulent presentation
Why feature of Neisseria gonorrhoeae means it is likely to die in transit?
Fastidious organism; dies easily. does not survive well in less than ideal growth conditions (i.e. outside the body.)
Describe the pathogenesis of Neisseria gonorrhoeae
Attaches to host epithelial cells and is endocytosed into the cell to replicate and then released into the subepithelial space.
Typical urethral infections result in prominent inflammation & release of toxic factors that attract neutrophilic leukocytes.
Describe the pathogenesis of herpes simplex virus in GU infections
Primary infection (may be asymptomatic - intermittent virus shedding can occur in the absence of symptoms)
- > Virus migrates to sacral root ganglion and “hides” from the immune system there (probably remains for life)
- > Virus can reactivate from there causing recurrent genital herpes attacks (trigger factors for this not understood)
Virus replicates in dermis & epidermis. Gets into nerve endings of sensory and autonomic nerves. Inflammation at nerve endings → exquisitely painful multiple small vesicles, which are easily deroofed
Viral shedding is higher, symptoms are more severe and recurrence is more likely in which type of herpes simplex virus?
HSV2
