Skildum: Micro of the Vagina and Penis Flashcards
which molecule has an inhibitory effet on other pro-inflammatory cytokines?
Il-1, IL-2, IL-10, TNF, IFNgamma
IL-10
what receptors recognize common molecular patterns in pathogens and mediate innate immune response such as ctyokine adn chemokine production? B7/CD28 MHCI MHCII T cell receptors Toll like receptors (TLR)
Toll Like Receptors
what is the normal state of the vagina: aerobic or anaerobic?
anaerobic
what are the characteristics of Lactobacilli?
gram positive rods/bacilli and facultative anaerobes
what does the vaginal microbial community depend on ?
ESTROGEN
what is the main product that prevents colonization by bacteria?
lactic acid production from lactobacilli, lowers pH
Which type of lactate can be taken up by host cells (immune cells) through monocarboxylate transporters (MCTs)? D or L
L-lactate. D-lactate is NOT transported into host cells. apparently the human version only makes one form of it.
what does lactobacillus possess that can interconvert L- and D- lactate?
Lactate racemase (LAR)
by what ENZYME do lactobacilli make hydrogen peroxide from pyruvate?
pyruvate oxidase (PO) or glucose oxidase
what type of lactobacilli is most abundant in healthy women? L. gasseri, L. iners, L. cripsatus, L.jensenii
L.iners, which does not produce hydrogen peroxide.
T or F: hydrogen peroxide does inhibit growth of vaginal pathogens.
FALSE. h202 DOES NOT inhibit growth e.g. Gardnerella vaginosis
_____ form a pore in the target cell’s membrane, resulting in depolarization and outflow of cytoplasmic contents.
bacteriocins
what three things can occur due to disruptions in the vaginal microbiome?
Bacterial vaginosis, PID, toxic shock syndrome
T or F: Bacterial vaginosis is not caused by a single pathogen.
True. it is due to a DISRUPTION of the normal vaginal microflora.
what is a gram variable facultative anaerobic bacilli that can cause BV
gardnerella vaginalis
Tiny, lack of cell wall, require cholesterol in growth media. NAME that organism that can cause BV!
Mycoplasma hominis
gram negative anaerobic motile curved rod that can cause BV. Name that organism!
Mobiluncus sp.
gram positive, anaerobic, elliptical cocci or rod shapped organism that can cause BV. NAME that organism!
Atopobium vaginae
how do you diagnose BV?
by symptoms: Amsel criteria. By microflora composition: Nugent score
What do you treat BV with?
Oral/intravaginal metronidazole. boric acid for symptom relief.
T or F: Metronidazole can by reduced to its active form in anaerobic and aerobic organisms.
FALSE. ONLY BE REDUCED IN ANAEROBIC ORGANISMS.
Gram negative diplococci, non-motile, not acid fast, oxidase positive that is associated with PID. Name that organism!
Neisseria gonorrhoeae
Gram negative obligate intracellular parasite associated with PID. Name that organism!
chylamydia trachomatis
what can often accompany Neisseria and Chlamydia that is gram negative coccobaciili that can cause PID?
H. influenza
what can often accompany Neisseria and Chlamydia that is gram positive chained cocci, facultative anaerobic and can cause PID?
Streptococcus pyogenes.
what is an emerging microorganism, associated with PID that is tiny, doesnt have a cell wall, requires cholesterol in growth media?
Mycoplasma genitalium
what is the mechanism for Ceftriaxone?
Cephalosporin derivatives that binds penicillin binding proteins and inhibits bacterial cell wall synthesis, resulting in osmotic imbalance and death of dividing cells. It is effective against bacteria that produce b-lactamase.
Doxycyline MOA?
binds to bacteria’s 30S ribosome and prevents tRNA binding, preventing protein synthesis
what else can you add to the treatment of PID with Ceftriaxone and docycyline?
metronidazole! action require a redox reaction only possible in anaerobes.
A female of reproductive age comes into your office with a fever, hypotension, a diffuse rash, and some organ dysfuction (renal, hepatic, muscle). What does she most likely have? what is it most likely associated with?
Toxic shock syndrome (TSS). 90% cases associated with Staph. aureus.
gram positive cocci, catalase + and coagulase +. name that organism!
staph aureus
T or F: Superantigens produced by bacteria bind both TCR and MHC II, creating an immunological synapse with a specific antigen. This causes activation of T cells regardless of the specificity to their TCR.
FALSE. —creating an immunological synapse without any specific antigen
T or F: PID’s cause is usually identified.
False. the organism is usually not identified, treatment is given based on symptoms.
what is the pathogenesis of TSS?
S. aureus colonization –SaPI1–> TSST-1 –> superantigen binding to the interaction between helper T cell (Th1 response–> IL-2 and IFNgamma) and macrophage –>IL-1 and TNF
What is TSST-1 encoded from?
SaPI1 pathogenicity island.
wowza, what is a pathogenicity island?
regions that contain NON-essential genes (so bacteria can live w/o them). they encode toxins or other proteins that enhance the virulence of the bacteira
By what mode of action are SaPI1 pathogenicity islands spread?
(A) transformation
B) transduction
C) conjugation
PHAGE transduction. therefore SaPI1 being integrating into CHROMOSOMAL DNA- therefore NOT good if it spreads throughout the Staph aureus community!
____ has a central role in the generation and propagation of the inflammatory response.
transcription factor Nuclear Factor kB (NFkB)
T or F: Patients with S. aureus sepsis (bacteria present in blood) rarely get Toxic Shock Syndrome
True.
T or F: Staph aureus’ superantigen can activated every T cell in the body at the same time
True. activated APC and T cell that are close to one another by ligated them or making them interact
T or F: Patients with Toxic shock syndrome almost always have positive S. aureus blood cultures.
FALSE. RARELY have + staph aureus blood cultures.
T or F: the penis microbiome in healthy males is different than that of the vaginal microbiome in healthy reproductive age women.
FALSE. they are BOTH DOMINATED BY LACTOBACILLUS
T or F: being circumcised decreases the protection from pathogens.
FALSE. Circumcision has a well documented effect on HIV transmission.
Circumcision also reduces incidence bacterial vaginosis in their partners.
One hypothesis is that circumcision alters the microbial community on or in the penis and increases protection from pathogens.
T or F: circumcision shifts the microbial community towards aerobic bacteria. what does this do to the immune response?
TRUE. this reduces inflammation and reduces the number of CD4+/CCR5+ macrophages in the urethra
A male comes in with some pain, swelling in his groin area, prevents with a fever and has dysuria. What does he most likely have?
Epididymitis
Chylamydia trachomatis and Neisseria gonorrheae is usually a cause of epididymitis in what age of men?
younger than 35 yrs
E. coli and Pseudomonas species are usually the cause of Epididymitis in men of what age?
men 35 yrs +
what is generally the cause of epididymitis in prepubertal boys?
E. coli
What would you treat a prepubertal epididymitis case with?
Quinalone e.g. levofloxacin
what would you treat middle age men associated epididymitis with?
doxycycline + ceftriaxone
T or F: giving an antibiotic for Toxic Shock Syndrome would help with the acute symptoms with a 17 y o female presenting to the E.R.
FALSE. TSS is caused by a TOXIN and therefore you should give fluid resuscitation, acetominopehn and vasopressors.
