STDs Flashcards
What bugs can cause urethritis?
Neisseria gonorrhea
Chlamydia trachomatis
Mycoplasma genitalium
Of the three causes of urethritis, which one is a gram- diplococci? What else is a distinguishing factor?
N. Gonorrhea
Also oxidase+
How N. gonorrhea be distinguished from N. meningitides?
N. gonorrhea only oxidizes glucose
N. meningitides oxidizes BOTH glucose and maltose
When is gonorrhea most common?
With menstruation or with an IUD
What is a telltale sign of gonorrhea?
Septic arthritis in sexually active people
Gonorrhea produces a discharge. What does it look like?
Gonorrhea → purulent discharge
What are some possible consequences of untreated gonorrhea?
PID
Ectopic pregnancy
Sterility
Fitz-Hugh-Curtis syndrome
What is Fitz-Hugh-Curtis syndrome?
PID with an inflamed liver capsule
What virulence factors does gonorrhea have?
Pili
IgA protease
What does having pili do for gonorrhea?
Allows for attachment to mucosal cells (urethra or vagina)
What is the result of gonorrhea killing ciliated cells?
Inflammatory response → urethritis (men) or cervicitis (women)
Besides seeing a gram- diplococci on a gram stain and evidence of the ability to metabolize glucose, what else can be done to diagnose a N. gonorrheal infection?
N. gonorrhea selectively grows on Thayer-Martin media
How is gonorrhea treated?
Ceftriaxone → for N. gonorrhea
Doxycycline → for the probably concurrent Chlamydia
Is Chlamydia gram- or gram+?
Neither
What kind of bacteria is Chlamydia?
Obligate intracellular parasite
Where does Chlamydia replicate in a host cell?
Chlamydia replicates in inclusion bodies
What serovars of Chlamydia are spread via sex?
L1-L3 cause Lymphogranuloma Venereum (LGV)
Does Chlamydia cause a discharge?
Yes…significant amount of a clear discharge
Other than a clear discharge, how else does Chlamydia present?
Painless ulcers that heal…but then there is regional lymphadenopathy that can lead to draining sinuses and proctitis or renal stricture
What are some complications of untreated Chlamydia?
Females → Fitz-Hugh-Curtis syndrome
Males → Reiter’s syndrome
What is Reiter’s syndrome? Is there a specific HLA type patient more likely to develop Reiter’s syndrome?
Reactive arthritis…also conjunctivitis
HLA-B27 is most likely to develop Reiter’s syndrome
How is Chlamydia diagnosed?
PCR
Iodine stain+
Giemsa stain+
How is Chlamydia treated?
Azithromycin
Tetracyclines
Erythromycin (oral/eye drops…for neonates)
What is a non-cyst forming protozoan that can cause vaginitis?
Trichomonas vaginalis
How does trichomonas vaginalis present?
Itching
Copious yellowish discharge
What can potentially happen if a pregnant woman is infected by trichomonas?
Premature labor
What is seen on a wet mount of vaginal/urethral discharge that would be diagnostic of trichomonas?
Tear-drop shaped trophozoites with 5 flagella and 1 nucleus
What is the vaginal pH with a trichomonas infection?
Higher than 4.5 (4.5 is normal)
How is trichomonas treated? Who all gets it?
Metronidazole
Patient AND partner
What bacteria can cause Bacterial Vaginosis (BV)?
Gardnerella spp.
Mobiluncus spp.
How is gardnerella BV diagnosed?
Gram stain → clue cell
KOH amine test → presence of amines
How does vaginosis present?
Moderate amount of gray/white very SMELLY discharge
What causes copious secretion of a cottage cheese like discharge?
Candida albicans
When is candida albicans likely to occur?
After an antibiotic regimen or in immunocompromised patients
How is candida diagnosed?
Pseudohyphae and budding yeast on tissue scrapings
What is Treponema Pallidum?
Spirochete bacteria that causes syphilis
How does T. pallidum initially present?
The first sign of syphilis is a painless chancre at the inoculation site that remains up to 6 weeks
If left untreated, what can happen with a syphilis infection after the initial chancre heals?
Treponema pallidum disseminate and proliferate → 2° syphilis
What are the symptoms of 2° syphilis?
Condyloma lata
Maculopapular rash on palms and soles
Meningitis, hepatitis, arthritis, etc.
What is condyloma lata?
Wart-like painless lesions in moist areas
How long do symptoms of 2° syphilis remain?
Up to 6 weeks…cycles can repeat many times
If still untreated, what can happen if the treponema pallidum infection progresses to 3° syphilis?
Chronic inflammation of:
Bone and soft tissue (Gummas)
CV system (aortitis and AAA)
CNS (tabes dorsalis, general paralysis, Meningitis, Argyll Robertson)
What is tabes dorsalis?
Demyelination of the dorsal column (proprioception, vibration, and discriminatory touch)
What abnormalities can happen to an infant born to a mother with syphilis?
Stillbirth CN VIII deafness Saber shins Saddle nose Hutchinson's incisors
How is treponema pallidum diagnosed?
Dark-field microscopy (NOT gram stain)
Serological tests
Bunch of tests that can give false positives with SLE or mono
FTA-ABS (detects anti-treponemal antibodies)
How is syphilis treated?
Penicillin G
Is penicillin G oral or IV?
G is IV…GIVe penicillin G
What is a potential complication of treating treponema pallidum?
Jarish-Herxheimer reaction d/t release of endotoxin-like factors (fevers, chills, and myalgias)
Which HSV typically infects below the waistline?
HSV-2
HSV-1 potentially could after oral
What kind of genome does HSV have? Is it enveloped
HSV is a linear dsDNA, enveloped virus
How does herpes usually present?
Usually asymptomatic, but can cause vesicular lesions
Where does herpes remain latent?
In the lumbosacral ganglia…travels through sensory nerves
Can herpes cross placenta?
Yes…causes congenital defects, spontaneous abortion or neonatal encephalitis
How is herpes diagnosed?
PCR
Multinucleate giant cells on Tzanck smear of skin lesions
Eosinophilic Cowdry intranuclear inclusion bodies on skin biopsy
Fluorescent antibody test is available
How is herpes treated?
Acyclovir
What forms the normal vaginal flora of reproductive age women?
Candida
Lactobacillus
What forms the normal vaginal flora in young girls/old women?
Non-hemolytic strep
Staph
Corynbacterium
Lactobacillus
