Urogenital and STI Flashcards
describe UTI
- most frequent healthcare-associated infection
- often results when fecal bacteria is self-inoculated into urethra
- more common in females
what is the most common type of UTI
cystitis (bladder infection)
what is the number one cause of UTI
E. coli
true or false - >80% of cases are causes by uropathogenic strains of e. coli (UPEC)
true
is UPEC part of the normal GI microbiota
yes
what are signs and symptoms of bacterial cystitis
- dysuria = burning or pain upon urination
- urgency to urinate
- pyuria = pus in urine, cloudy, foul odor
- hematuria = blood in the urine
what are some complications of a UTI
- sometimes the UTI progresses to pyelonephritis
- the infection inflames the kidneys
- repeated episodes lead to scarring; can
cause kidney failure
describe vulvovaginal candidiasis
- aka vaginal yeast infection
- causative agent:
- candida albicans
- commensal yeast
- part of microbiota on mucosal surfaces
in mouth, skin, and female genital tract
- candida albicans
describe candida albicans
- it is part of normal vaginal microbiota in about third of all women
- infections are endogenous - derived from host’s own normal microbiota
what kind of pathogen is candida albicans
opportunistic fungal pathogen
- antibiotics, pregnancy, or menstruation can disrupt the balance of the normal vaginal microbiota and allow overgrowth
how is candida albicans transmitted
by contact
- rarely via sex
what are signs/symptoms of a yeast infection
- constant, intense itching and burning of vagina or vulva
- thick, clumpy whitish vaginal discharge
- vaginal mucosa usually red, swollen
what is the diagnosis of a yeast infection
- wet preparation of gram’s stain of vaginal discharge and examine microscopically
- yeast stain gram positive
what is the treatment of a yeast infection
- prescription oral antifungal in a single dose
- over-the-counter intravaginal cream
how are STI’s spread and are they reported
- spread through
- sexual contact (vaginal/penile, anal or oral)
- sometimes also vertical transmission
- majority of cases go unreported
MKE is #7 for bacterial
STIs
- gonorrhea, chlamydia, and syphilis
what is the common age to get infected with a bacterial STI in the U.S.
15-24 years old
what are some stigmas against STI
- failure to disclose disease or risk status
- failure to seek treatment
- underestimation of risk
what is the prevention of STI
- no vaccine for most STI (HPV is exception)
- widespread testing and treating those are infected; and contact tracing
- using latex condoms
- having a monogamous relationship with a non infected person
- abstaining from sex
what are some characteristics of bacterial STI
- survive poorly in the environment
- humans are the only known reservoir
- may be associated with sores or unusual discharge
how are bacterial STI transmitted
- via intimate physical contact
- oral, anal, vaginal/penile contact
- vertical transmission from mother to baby
during birth
describe neisseria gonorrheae
- neisseria is the only genus of gram-negative cocci that regularly causes disease in humans
- arranged as diplococci
- informal name = gonoccocci
- virulence factors include fimbriae and endotoxin
true or false - men are more symptomatic than women for gonorrhea and women are often asymptomatic
true
what are signs/symptoms of gonorrhea in men
- gonococcal urethritis
- thick, purulent discharge from the penis
- pain and burning during urination
- noticeable, unpleasant symptoms -> seek treatment
- preventing serious sequelae, but not soon
enough to prevent transmission to other
sex partners
- preventing serious sequelae, but not soon
what are signs/symptoms of gonorrhea in women
- infects mucosa of uterine cervix and urethral mucosa but is often asymptomatic
- cervicitis = if symptomatic, discharge from the vagina or intermenstrual bleeding
- bacteria may spread upward to the fallopian tubes, causing salpingitis, a manifestation of pelvic inflammatory disease (PID)
- often undiagnosed and untreated until PID complications develop
describe pelvic inflammatory disease (PID)
- ascending infection of the uterus, fallopian tubes, ovaries, and adjacent peritoneal linings
- abdominal pain and tenderness
- complications of salpingitis:
- tubal scarring
- infertility and/or ectopic pregnancy and/or
chronic pelvic pain
describe gonococcal ophthalmia neonatorum
- aka neonatal conjuctivitis
- infection occurs during childbirth from infected mothers
- swelling and purulent discharge
- can progress rapidly to corneal damage -> blindness
true or false - gonococcal ophthalmia neonatorum is more severe than chalmydia
true
what kind of treatment is used for gonococcal ophthalmia neonatorum
- prophylactic treatment
- uses silver nitrate or erythromycin
application in eyes of all newborns within
one hour
- uses silver nitrate or erythromycin
which is correct description of what a lab technician would view under the microscope when analyzing a gram stain of vaginal discharge from a patient with gonorrhea?
- gram positive cocci arranged in clusters
- gram positive bacilli
- gram negative diplococci
- gram negative cocci arranged in clusters
- gram negative bacilli
gram negative diplococci
what is the diagnosis of gonorrhea
- gram negative diplococci in gram stain of patient specimen
- interfering microbiota complicates interpretation of gram stain for women
- asymptomatic cases identified by PCR
what is the treatment of gonorrhea
- there were several strains in 2011 that were resistant to at least one antibiotic
- treat with combination antibiotic therapy
describe chlamydia trachomatis
- gram-negative bact
- tiny, pleomorphic cells
- non-motile
- obligate intracellular pathogen
- depend on host cell for ATP production
- grows inside vesicles within host cells
what is the developmental cycle of chlamydia trachomatis
- elementary bodies are the infectious form
- reticulate bodies are the replicating form
- both forms develop within the vesicle of a
host cell
- both forms develop within the vesicle of a
describe elementary body (EB) of chlamydial life cycle
- small
- non-replicating
- extracellular
- infectious
describe reticulate body (RB) of chlamydial life cycle
- larger
- replicating
- intracellular
- noninfectious
what does an elevated neutrophil count most likely indicate?
- a bacterial infection
- a viral infection
- an antibody repsonse
a bacterial infection (chlamydia)
case study - a 25 year old man comes to the clinic complaining of a penile discharge for three days. A gram stain of the urethral discharge was performed. Numerous neutrophils were seen, but there were no visible bacteria. The sexual history revealed that the patient had been having unprotected sexual relations with one female partner during the past 6 months. The girlfriend had no symptoms and felt well. What bacterial infection do they most likely have?
chlamydia
Like gonorrhea, the majority of infected females are asymptomatic and therefore persist untreated. This can sometimes lead to infertility. How do you think chlamydia may result in infertility?
- C. trachomatis destroys oocytes
- inflammation and consequent scarring block the fallopian tubes
- granulomas form around the bacteria in the vagina blocking sperm
- C. trachomatis secretes an enzyme that destroys sperm
inflammation and consequent scarring block the fallopian tubes
describe chlamydia in males
- about 75% show symptoms
- non-gonococcal urethritis (NGU)
- watery thin gray-white discharge from penis
- dysuria
describe chlamydia in female
- usually (about 85%) asymptomatic
- PID may develop -> salpingitis
- increases risk for infertility, ectopic pregnancy, and chronic pelvic pain
describe chlamydial disease in newborns
- baby becomes infected from mother as it passes through birth canal
- develop:
- chlamydial pneumonia
- chlamydial ophthalmia neonatorum
describe chlamydial ophthalmia neonatorum
- aka neonatal conjunctivitis
- discharge is usually more watery in nature and eyes are less inflamed than with gonococcal ophthalmia neonatorum
routine chlamydia screening is recommended for:
- sexually active women under age 25
- men and women at high risk (I.e., not in a monogamous relationship)
- pregnant women
what is the diagnosis and treatment of chlamydia
- urine or cervical swab is tested via PCR for chlamydial DNA
- because it is an obligate intracellular
parasite, chlamydia can’t be cultured on
agar - gram strain of urethral and cervical shows
discharge shows many PMNs but no
bacteria
- because it is an obligate intracellular
- treat with antibiotics
describe treponema pallidum
- gram negative (lacks LPS)
- don’t stain well with gram stain due to thin
cell wall
- don’t stain well with gram stain due to thin
- causes syphilis which can be a chronic disease
what is the shape of treponema pallidum
- spirochete
- posses endoflagella -> motility
true or false - treponema pallidum can cross the placenta and cause developmental defects (teratogen)
true
how does treponema pallidum evade the immune response
because it lacks outer membrane proteins and LPS
what are the stages of syphilis
- inoculation
- primary syphilis
- secondary syphilis
- latent syphilis
- tertiary syphilis
describe the inoculation stage of syphilis
- organism spreads by lymph and blood
- no symptoms: average incubation period is 3 weeks
describe primary syphilis stage
- chancre = may be at site of inoculation
- on penis, labia, or vagina
how many weeks is syphilis asymptomatic
about up to 24 weeks
describe secondary syphilis stage
- rash = may be accompanied by hepatitis, meningitis, or glomerulonephritis
describe latent syphilis stage
- no symptoms = treponema pallidum present in latent state
- latent period may last 3 to 30 years
- could move on to tertiary syphilis or revert back to secondary syphilis
describe tertiary syphilis
- gumma of skin = these lesions may also occur in deep organs, along with CNS degeneration and ascending aortic aneurysm
pathogenesis of primary syphilis
- spirochete binds to the epithelium, multiplies, and forms a single, painless, red ulcerated sore (chancre)
- genital ulcers increase risk for acquiring
and transmitting HIV
- genital ulcers increase risk for acquiring
- fluid from the chancre is highly infectious
- chancre spontaneously heals as the spirochete moves into the blood
true or false - the earlier syphilis is diagnosed, the easier it is to treat with antibiotics
true
pathogenesis of secondary syphilis
- spirochete is multiplying in the bloodstream (“bacteremia”)
- flu-like symptoms and non-itchy macular rash
- rash may be so faint as to not be noticed
- very infectious at this stage
pathogenesis of latent syphilis
- enters latent phase that lasts 3-30 years
- less likely to be infectious to others the longer the latent period lasts
- can resolve, revert to secondary syphilis or progress to tertiary syphilis
pathogenesis tertiary syphilis
- may occur 10-20 years after initial infection
- diffuse chronic inflammation and destruction of any organ
- symptoms are due to host response to pathogen
- generally not contagious
what are the three major components of tertiary syphilis
- granulomatous change = gummas that damage organs
- cardiovascular syphilis = aortic aneurysm or coronary stenosis
- neurosyphilis = tabes dorsalis which is nerve degeneration in the dorsal columns of the spinal cord and subsequent ataxia; meningitis (a manifestation of neurosyphilis) can occur in earlier stages
gumma is a form of
granuloma
describe congenital syphilis
- T. pallidum is a fetal teratogen
- TORCHeS panel of prenatal tests
- most common infections associated with
congenital anomalies - Toxoplasmosis, “Other” infections (HIV,
syphilis, VZV), Rubella, CMV, Herpes
simplex virus
- most common infections associated with
- TORCHeS panel of prenatal tests
what are some signs/symptoms of congenital syphilis
- spontaneous abortion, stillbirth, and neonatal death common
- nearly all survivors develop serious signs/symptoms
- such as blindness, deafness, and bone
malformations
- such as blindness, deafness, and bone
what is the diagnosis of congenital syphilis
- culture on agar media is not possible
- direct fluorescent antibody staining or darkfield microscopy useful is mucosal ulcers are observed in primary stage
- serological tests:
- nontreponemal tests (VDRL test and RPR
test) - measure antibodies that develop
against lipids released from damaged host
cells during the early stages of disease;
used for initial diagnostics screening - treponemal tests - detect antibodies
specifically directs against T. pallidum as a
confirmatory test
- nontreponemal tests (VDRL test and RPR
a bisexual male seeks medical attention when a single ulcer appears on the shaft of his penis. He is diagnosed with syphilis. His current female sexual partner has no ulcer or other symptoms. She denied that she was the source; however, her syphilis serological test is positive. How can you explain this?
- she is not infected with the same pathogen as her male partner
- females typically do not show symptoms compared to males
- the pathogen is latent
the pathogen is latent
describe trichomonas vaginalis
- urogential protozoan
- only exists as a trophozoite, no cyst form
- high motility
- found in urethras and vaginas of women and urethras and prostate glands of men
- reservoir: humans
is trichomonas vaginalis an STI
yes
what are the signs/symptoms of trichomoniasis in men
- most infections are asymptomatic
- urethritis
- occasionally thin, milky penile discharge; burning upon urination
what are the signs/symptoms of trichomoniasis in females
- foul-smelling
- green-to-yellow frothy vaginal discharge; itchy and burning
what is the diagnosis and treatment of trichomoniasis
- commonly diagnosed with wet mount of genital secretions showing motile trophozoites
- molecular methods (PCR) are more sensitive and specific and therefore preferred
- curable with antimicrobials
what is the pathogen for genital herpes
- HSV-2 = causes most cases
- HSV-1 = causes remainder of cases
what is the pathogenesis of genital herpes
- kills epithelial cells at the infection site
- create small, fluid-filled blisters (vesicles)
- rupture produces itchy, painful ulcerations
describe latency of genital herpes
- establish latency in ganglia of sensory neurons and can later reactivate
- can have recurrent episodes of genital herpes
- once infected, individual forever at risk of transmitting
most people infected with HSV are asymptomatic or symptomatic and are their symptoms mild or severe
asymptomatic or have very mild symptoms that go unnnoticed
- but transmission can still occur even if host is asymptomatic or has mild lesions
what is the difference between primary vs recurrent genital herpes
- primary outbreak = longer duration, increased viral shedding and sometimes additional symptoms such as fever and body aches
- recurrent episodes = common, but symptoms are typically shorter in duration and less severe than the first outbreak
what are some signs/symptoms of genital herpes
- painful vesicular lesions with an erythematous base on the genitalia
- sometimes dysuria present
- genital herpes quadruples the risk of HIV infection
what is HSV diagnosis
- the history and clinical presentation is often sufficient to diagnose the HSV infection
- definitive confirmation by testing lesion fluid for the presence of HSV DNA by PCR
describe neonatal herpes
- typically transmits at birth but HSV-2 (and HSV-1) are teratogens and can cross the placenta
- disseminated infection of neonate is often deadly or leads to severe neurological issues
- C-section if mother is symptomatic at delivery
what happens in the rare cases of neonatal herpes when the infections occur before birth when the virus cross the placenta
- spontaneous abortion or severe disabilities if the fetus survives
- TORCHeS panel of prenatal tests
what is the treatment for HSV
- there is no cure for herpes
- antiviral meds can prevent or shorten outbreaks during the period of time the person takes the meds
- daily suppressive therapy for herpes can reduce the likelihood of transmission to partners
what is the most common STI
HPV
most genital HPV infection are
transient, asymptomatic, and have no clinical consequences
how is HPV transmitted? how long does it last? what does it cause?
- transmitted by sexual contact or by direct skin contact
- over 90% infections clear within two years
- causes genital warts and cancer
describe HPV
- naked virus
- DNA genome
different types of HPV viruses have different clinical consequences, what are some
- cutaneous papillomas (eg skin warts)
- genital papillomas (eg genital warts); low malignancy risk
- cancer; high malignancy risk
high risk genital HPV types include
- low-grade cervical abnormalities
- cancer precursors
- anogenital cancers
low risk genital HPV types include
- low-grade cervical abnormalities
- genital warts
- laryngeal papillomas
true or false - most women with high-risk HPV infection have normal Pap test results and never develop cellular changes or cervical cancer
true
describe genital warts
- warts are benign growths of the squamous epithelium
- large (“cauliflower-like”) growths called condyloma acuminata may form
true or false - HPV is present in >90% of all cervical cancers
true
what types of HPV account for 70% of cervical cancer
16 and 18 (“high risk types”)
a pap smear is a screening test for what type of cancer
cervical
what does a pap smear screen for
- pap smear screens for abnormal changes in cervical cells
- PCR analysis of cervical swabs to detect HPV DNA
- if both tests negative, repeat in 3 years
the most common cancer in males are on the anus, penis, or oropharynx
oropharynx
the most common cancer in females are on the anus, oropharynx, cervix, vagina, or vulva
cervix
what is the prevention of HPV
- abstinence, monogamy
- condoms not fully protective
- subunit vaccine
- protect against 9 types of HPV
- includes HPV 16 and 18
- also includes types that cause 90% of all
genital warts
HPV 16 and 18 cause 70% of what kind of cancer and 80% of what other kind of cancer
- 70% of cervical cancer
- 80% of anal cancer
