Sexually Transmitted Infections Flashcards Preview

Introductory Microbiology > Sexually Transmitted Infections > Flashcards

Flashcards in Sexually Transmitted Infections Deck (76)
Loading flashcards...
1
Q

What STIs are considered notifiable?

A
  • Chlamydia
  • Gonorrhoea
  • Syphilis
2
Q

What STIs are non-notifiable?

A
  • Herpes Simplex Virus (HSV)

- Human Papilloma Virus (HPV)

3
Q

What are three reasons understanding STIs is significant?

A

1) High burden of disease - represents 70% of all notifiable diseases in Canada, Chlamydia accounting for 50%, and there has been a steady rise in STIs since 1997
2) Sequelae - sterility, ectopic pregnancy, birth defects, miscarriage, cancer, chronic pain, psychiatric illness, 2-5 fold increased risk of HIV transmission
3) Determinants of health - poverty, STIs form a high cost to society, lack of access to resources

4
Q

In women, many STIs are…

A

Asymptomatic

5
Q

Individuals infected with both HIV and another STI…

A

Shed HIV at a much higher rate; therefore has a synergistic nature

6
Q

Individuals with some STIs are more at risk for HIV because…

A

More portals of entry due to lesions

7
Q

Why have chlamydia and gonorrhoea rates risen since the late ’90s?

A

1) Increased screening related to new non-invasive NAAT/PCR allow more people to be tested, and improved contact tracing
2) Better therapies prevent adaptive immunity from developing, causing recurrences
3) Not treating people to cure with antibiotics, so increasing MDR strains
4) Condom fatigue; cost to life is less due to improved treatment

8
Q

Why are chlamydia rates higher in women?

A

Rates are higher in women because they are more likely to see their HCP regularly due to things like B/C renewal or pap smears

9
Q

What is the epidemiology of chlamydia trachomatis?

A
  • most prevalent bacterial STI in Canada
  • rates have increased greatly
  • most people affected aged 15-29
  • rates increasing in the 25-29 age group
  • females more than 2/3 of reported cases
10
Q

What are potential sequelae of chlamydia?

A

Females: PID, infertility, ectopic pregnancy, chronic pelvic pain, Reiter’s syndrome

Males: Epididymo-orchitis, Reiter’s syndrome

Newborn: trachoma, pneumonia

11
Q

What is Reiter’s syndrome?

A

Reactive arthritis; swollen joints and decreased ROM that resolves over time

12
Q

What is epididymo-orchitis

A

Swelling of the epididymis and testes that can lead to infertility

13
Q

What is chlamydia trachomatis and how does it manifest?

A
  • gram negative, obligate intracellular bacteria
  • enters body through abrasions or lacerations and infects mucosal cells of the pharynx, urethra, cervix, uterus, fallopian tubes, anus or rectum
  • lesion at site of infection commonly ignored
  • lesions are small, painless and heal rapidly
  • headache, fever and muscle pain may occur 40 hours post-infection
  • signs and symptoms result from the destruction of infected cells and the resulting inflammatory response
  • incubation period of 2-3 weeks but as long as 6 weeks
  • often symptoms go unnoticed
14
Q

What symptoms of chlamydia do females experience?

A
  • most infected females are asymptomatic (70%)
    Symptoms (if present) include:
  • URETHRITIS causing dysuria
  • CERVICITIS causing painful intercourse, lower abdominal pain, purulent discharge, abnormal vaginal bleeding, increased risk for cervical cancer (HPV co-infection)
  • PROCTITIS (usually asymptomatic and can occur in absence of anal sex)
15
Q

What is pelvic inflammatory disease (PID)?

A
  • infection and inflammation of the upper genital tract
  • may cause fever, lower abdominal pain, abnormal discharge
  • adnexal and cervical motion tenderness upon palpation
  • caused by Chlamydia trachomatis and Neisseria gonorrhoeae
  • incubation period of
    months to years post-infection
  • 2/3 of cases unrecognized (silent PID)
  • younger age associated with higher risk (adolescents vs. young adults)
  • diagnosis based on symptoms, microbiology & diagnostic imaging
16
Q

What are possible sequelae of PID?

A
  • ectopic pregnancy, sterility, chronic pelvic pain

- 10% risk after first episode, rises to 40% risk after third episode of PID

17
Q

How is PID treated?

A
  • early diagnosis and treatment are essential to maintaining fertility
  • symptoms should resolve within 48-72 hrs post-treatment
  • hospitalization if: patient is pregnant, unable to tolerate oral therapy or unresponsive to oral therapy, severe pain, nausea/vomiting, or if client presents with adherence issues
  • complex inpatient dosage regimen with Cefoxitin and Doxycyline
  • oral therapy 24 hrs after clinical improvement is observed
  • 14 day course of oral therapy
  • outpatient treatment regimen with single-dose Ceftriaxone, Oxycyline and Metronidazole for 14 days
18
Q

What symptoms of chlamydia do males experience?

A
  • significant proportion of men are asymptomatic (50%)
    Symptoms (if present) include:
  • URETHRITIS causing dysuria and urethral discharge and itch
  • EPIDIDYMO-ORCHITIS causing testicular pain and sterility
  • PROCTITIS commonly associated with anal sex but may also be caused by lymphatic spread from urethra to rectum
19
Q

Male urethral discharge associated with chlamydia may be…

A

Mistaken for pre-ejaculate and ignored

20
Q

Who should be treated for chlamydia?

A
  • positive lab result for Chlamydia trachomatis
  • individuals who are sexually active and symptomatic
  • diagnosis of chlamydia in a sexual partner within 60 days, or last sexual partner
21
Q

How is chlamydia treated?

A
  • Azithromycin PO single dose, or
  • Doxycycline PO for 7 days
  • clients should abstain from sexual intercourse for 7 days post-treatment
  • clients should be re-tested 6 months later to ensure they are cured
22
Q

Why did rates of gonorrhoea drop in the mid ’90s before rising again?

A

Introduction of single dose antibiotic therapy

23
Q

What is Neisseria gonorrhoeae and how does it manifest?

A
  • gram negative facultative intracellular bacteria
  • adheres via fimbriae and capsules to epithelial cells in the mucous membranes of the pharynx, urethra, cervix, uterus, uterine tubes, anus or rectum
  • fimbriae allow N. gonorrhoeae to attach to sperm cells and enter female reproductive tract, meaning a higher risk of PID
  • phagocytized bacteria can survive and multiply in neutrophils, traveling to distal sites in the body such as joints, meninges, heart
  • incubation period of 2-7 days
24
Q

What is the epidemiology of gonorrhoea?

A
  • second most commonly reported bacterial STI in Canada
  • males account for almost 2/3 of nationally reported cases
  • associated male urethral discharge is difficult to ignore
25
Q

What are potential sequelae of gonorrhoea?

A

Females: PID, infertility, ectopic pregnancy, chronic pelvic pain, Reiter syndrome, cervical cancer, disseminated infection

Males: Epididymo-orchitis, Reiter syndrome, disseminated infection

Neonates: ophthalmia neonatorum, sepsis

26
Q

What symptoms of gonorrhoea do females experience?

A
  • most infected females are asymptomatic (75%)
    Symptoms (if present) include:
  • PHARYNGITIS
  • URETHRITIS causing dysuria
  • CERVICITIS causing abnormal vaginal bleeding, lower abdominal pain, painful intercourse
  • PROCTITIS (can occur in absence of anal sex)
  • DISSEMINATED INFECTION
27
Q

What symptoms of gonorrhoea do males experience?

A
  • most infected males are symptomatic
    Symptoms (if present) include:
  • PHARYNGITIS
  • URETHRITIS causing dysuria, urethral itch and highly evident urethral discharge
  • EPIDIDYMO-ORCHITIS causing testicular pain and sterility
  • PROCTITIS
  • DISSEMINATED INFECTION
28
Q

How is gonorrhoea treated?

A
  • anogenital and pharyngeal ≥ 9 years of age
  • treated with Ceftriaxone and Azithromycin
  • patient should abstain from sexual intercourse for 7 days post-treatment
  • clients should be re-tested 6 months later
29
Q

Who should be treated for gonorrhoea?

A
  • positive lab result for N. gonorrhoeae
  • sexually active and symptomatic
  • diagnosis of gonorrhoea in a sexual partner within 60 days, or last sexual partner
  • also treated presumptively for chlamydia because those with gonorrhoea also often have chlamydia, but not vice-versa
30
Q

What antibiotics are gonococcal strains resistant to?

A
  • Penicillin
  • Tetracycline
  • Erythromycin
  • Aminoglycosides
  • Fluoroquinolones
31
Q

What challenges do we face with gonorrhoea?

A
  • worldwide spread of antibiotic resistant strains
  • no long-term specific immunity against N. gonorrhoeae
  • single individual can be infected multiple times
  • high variability in surface antigens across strains
  • vaccine development unlikely
  • perpetuates HIV because it greatly increases risk of transmission
32
Q

Clients should always be tested for cure in cases of…

A

Pharyngitis, persistence of symptoms, alternate treatment choice, cases linked to MDR strains
- cultures recommended whenever possible

33
Q

How does gonococcal antibiotic resistance perpetuate the HIV epidemic?

A
  • individuals co-infected with HIV and gonorrhea shed the virus at a much higher rate than those infected with HIV alone
  • prolonged periods of infection due to treatment failure (due to antibiotic resistance) increases the likelihood of HIV transmission in co-infected individuals
34
Q

Who should undergo chlamydia and gonorrhea screening?

A
  • all sexually active females under 25 years of age
  • all pregnant women; offers significant reduction in perinatal mortality
  • for sexually active males and other females, screen if the following risk factors present: sexual contact with chlamydia/gonorrhea-infected partner; new sexual partner or more than 2 partners in the past year; history of STI; IV drug users; inmates; sex workers; street youth
35
Q

How are cultures used to test for chlamydia and gonorrhoea?

A
  • endocervical or vaginal (female) & urethral (male and female) sampling
  • pharyngeal and rectal samples if applicable
  • expensive, difficult sample to obtain from male patients
  • cannot obtain from urine
36
Q

How are Nucleic Acid Amplification Tests (NAATs) used to test chlamydia and gonorrhoea?

A
  • can use urine: easier sample to collect from male patients
  • cheaper than cultures, very sensitive
  • impedes tracking of antibiotic resistant microorganisms
  • not approved for use in pharyngeal or rectal laboratory diagnosis
37
Q

Syphilis is much higher in…

A

Men than women, especially men that have sex with other men

38
Q

Rates of syphilis dropped in the ___ but began rising again in the ___.

A

60s, 2000s

39
Q

What age group is most affected by syphilis?

A

Males 25-39 years of age

40
Q

What is the causative pathogen of syphilis?

A

Treponema pallidum

41
Q

What is congenital syphilis?

A
  • infectious syphilis can be transmitted from mother to fetus during pregnancy or delivery
  • primary and secondary syphilis have a > 70% risk of transmission; early latent > 40% risk
  • can result in fetal death (40%), cerebral palsy, mental disability, organ malformation
  • all pregnant females in first trimester are screened
42
Q

What is the risk of infection rate from unprotected sex?

A

60% risk of infection from unprotected sexual contact with an infected partner, significant rate of co-infection with HIV

43
Q

Can those with HIV safely have sex with others with HIV?

A

No; there are different strains of HIV, can worsen prognosis if more than one strain is acquired

44
Q

What is primary syphilis?

A
  • infectious
  • characterized by small, hard and painless ulcers (chancres) occurring at site of infection; often ignored
  • regional lymphadenopathy
  • affects cervix, vulva, vaginal wall, penis, anus, mouth
  • manifests 21 days post-exposure and resolves within 3 - 6 weeks without treatment
45
Q

What is secondary syphilis?

A
  • infectious
  • systemic symptoms: rash, fever, malaise, headache, mucous membrane lesions, lymphadenopathy, meningitis
  • symptoms occur 1 to 2 months after resolution of the primary lesion and resolve within a few weeks
  • relapse can occur for up to 1 year, remain infectious for the entire duration
46
Q

The rash seen with syphilis…

A
  • does not itch or hurt and can last for months

- may be seen on the soles of the feet and palms of the hands; characteristic of syphilis

47
Q

What is early latent syphilis?

A
  • infectious

- asymptomatic phase seen < 1 year post-secondary stage

48
Q

What is late latent syphilis?

A
  • non-infectious
  • asymptomatic phase seen > 1 year post-secondary stage
  • no long-term complications may develop
49
Q

What is tertiary syphilis?

A
  • occurs years (10-30 years) after initial infection
  • increased occurrence in HIV-positive clients
  • manifests as cardiovascular syphilis, neurosyphilis, gumma
  • associated with inflammation and severe hyperimmune responses
50
Q

What is gumma?

A

Ulcer-like wounds related to inflammation

51
Q

How is syphilis diagnosed?

A
  • primary and secondary: symptoms, serologic testing & samples from lesions (except oral or anal lesions)
  • latent and tertiary: CSF, chest x-ray, physical & neurological exams, serology; challenging to diagnose due to timeline between infection and appearance of symptoms
52
Q

Neurosyphilis is sometimes misdiagnosed as…

A

Dementia

53
Q

Not everyone with tertiary syphilis will show…

A

A positive blood test

54
Q

How is syphilis treated?

A
  • primary, secondary, early latent:
    benzathine penicillin G (IM, single dose), refrain from sexual intercourse until all lesions are healed and/or 7 days post therapy
  • longer course of therapy for late latent, and tertiary
55
Q

Why are rates of chlamydia, gonorrhoea and syphilis all rising?

A
  • internet facilitating high risk partnering
  • safe-sex burnout; new generation of teens and young adults did not witness AIDS devastation
  • highly active antiretroviral therapy (HAART) makes AIDs less scary
  • multi-drug resistance
56
Q

What is genital herpes?

A
  • non-reportable disease
  • most cases of genital herpes associated with HSV2 vs HSV1
  • asymptomatic shedding and rate of reoccurrence greater with HSV2
  • doubles risk of HIV infection
  • incubation period of about 6 days
  • an estimated 60% of infections go unreported; clients do not link symptoms to genital HSV infection and 60% are asymptomatic
  • more than 50% individuals contract the disease from a partner that is unaware that they are infected
  • asymptomatic “silent” shedding of the virus facilitates transmission
57
Q

What are the primary manifestations of genital herpes?

A
  • clear, straw-coloured fluid-filled blisters appear first and then develop into painful, burning ulcers as they rupture
  • manifest 5-7 days post-infection
  • when blisters rupture, millions of virion are shed
  • systemic symptoms (58-62%) of fever, myalgia
  • tender lymphadenopathy (80%)
  • meningitis (16-26%)
  • males 16.5 days, females 22.7 days to resolve
58
Q

What are the secondary manifestations of genital herpes?

A
  • virus persists in a latent phase (hibernates within the nerve ganglia)
  • reoccurrence induced by emotional or physical stress (fever, menstrual cycle, mechanical irritation, fatigue, coitus, immunosuppression)
  • becomes active and triggers recurrent lesions (10% of primary)
  • reduced likelihood of systemic symptoms (5 - 12%)
  • prodromal syndrome (43-53%) lasting 1 - 2 days
    (pain, tingling, burning, itching, and skin sensitivity at sites where new blisters will form)
  • mean duration of 9.3 – 10.6 days
59
Q

How is genital herpes treated?

A
  • no cure for HSV
  • abstinence during prodromal period until lesions have resolved to prevent transmission
  • condom use not perfect
  • daily suppressive antiviral therapy (clients with 6 episodes/year)
  • VALACYCLOVIR 500 mg, PO daily; decreases frequency/severity of symptoms and reduces viral shedding and thus transmission by 48%
  • suppressive valacyclovir therapy 2x daily for pregnant women; initiate at 36 weeks until delivery
60
Q

What is HPV?

A
  • human papillomavirus
  • estimated to be the most common STI in Canada
  • not reportable
  • 70% of sexually active adults will acquire a genital tract HPV infection during their lifetime, majority of these infections resolve within 18 months
  • over 100 HPV genotypes exist
  • low risk and high risk
  • some have no effects
61
Q

What are the low risk vs high risk HPV genotypes?

A
  • 13 high risk (oncogenic) including 16 and 18; causes genital cancers (cervix, vulva, vagina, anus, penis) and oro-pharyngeal cancer
  • low risk (non-oncogenic) including 6 and 11; causes genital warts on cervix, vulva, vagina, anus, penis
62
Q

What are genital warts?

A

Painful lesions that typically present 3-4 months post-exposure

63
Q

How are genital warts treated?

A
  • treatment topical if number and size is small
  • if larger and more numerous, consider surgical excision, cryotherapy, laser, etc.
  • topical treatment with podofilox or imiquimod
  • TCA (trichloroacetic acid) or podophyllin if warts not responding to treatment
64
Q

Do we test for HPV?

A

No; we use pap smears to test for the outcome of high risk HPV, no routine testing for HPV itself

65
Q

How is HPV related to cervical cancer? How do screen?

A
  • HPV is a predisposing factor in the development of cervical cancer
  • types 16 and 18 are responsible for 70% of all cervical cancers
  • we use screening programs to detect cervical abnormalities, pre-cancerous lesions and cervical cancer due to HPV infection in women
  • begin screening at 21 yrs (if sexually active); if cytology is normal, then every 3 years; if abnormal, screen annually
66
Q

What are co-factors to cervical cancer?

A
  • smoking, long term use of oral contraceptives (> 5 years), higher number of pregnancies, other STIs, poor nutrition, multiple sex partners, sex at a young age, immunosuppression, genetic factors
67
Q

What is Gardasil? How does it work?

A
  • vaccine against HPV genotypes 16, 18, 6, 11
  • consists of VLPs assembled from recombinant HPV proteins
  • antibodies protect and prevent infection caused by viral strains covered in the vaccine
  • administered to females aged 9 - 45 and males 9 - 26
  • 3 doses over a 6 month period
  • covered for both females and males in grade 7
  • NOT effective in females with abnormal cytology or current HPV infection
  • duration of protection is unknown
  • protective antibodies persist for at least five years
68
Q

What are lower UTIs vs. upper UTIs?

A
  • lower urinary tract infections: urethritis, cystitis, prostatitis
  • upper urinary tract infections: acute pyelonephritis
69
Q

Who is most at risk for UTIs?

A
  • females
  • hospitalized and elderly patients
  • pregnant women
  • those with catheters
  • obstruction or neurogenic bladder
  • sexual activity
70
Q

When should urine for a UTI screen be collected during voiding?

A
  • midstream void
71
Q

What are the symptoms of a lower UTI?

A
  • fever
  • dysuria, frequency, urgency
  • incontinence
  • abdominal pain, flank tenderness
  • if severe: sepsis, altered LOC, confusion
72
Q

Why are pregnant women more at risk for UTIs and what are the complications?

A
  • due to decreased peristalsis in ureters and ureteral tone
  • increased risk of pyelonephritis (20-30%)
  • increases risk of premature delivery
  • increases neonatal mortality
73
Q

What will a urinalysis show if someone has a UTI?

A
  • leukocyte esterase (enzyme produced by neutrophils – indicative of active infection)
  • WBCs
  • bacteria (1000 bacteria/mL) – 90% pyelonephritogenic E. coli
  • nitrites (bacteria that cause UTIs make an enzyme that changes urinary nitrates to nitrites
  • increased protein levels
74
Q

A culture is used to…

A
  • identify the organism
75
Q

What is pyelonephritis? How is it treated?

A
  • ascending infection
  • UTI complication
  • severe abdominal, flank and back pain
  • fever (> 39°C) that persists for more than 2 days
  • chills, nausea, vomiting, fatigue
  • pyuria
  • sepsis & kidney damage
  • outpatient, if PO antibiotics are tolerated
  • hospitalization warranted in cases of sepsis and immunocompromised clients
76
Q

How are chronic UTIs prevented?

A
  • in females, after toileting, wipe area front to back to prevent contamination
  • frequent voiding
  • consuming 2 – 4 L of fluids per day
  • post-coital voiding
  • refrain from vaginal douching