Sexually transmitted diseases Flashcards
1
Q
What are some STIs caused by bacteria?
A
Syphilis - Treponema pallidum
Gonorrhoea - Neisseria gonorrhoeae
Non-gonococcal urethritis - Chlamydia trachomatis
Lymphogranuloma venereum (LGV) - Chlamydia trachomatis
Others (FYI)
- Non-gonococcal urethritis (Ureaplasma urealyticum, Mycoplasma genitalium)
- Chancroid - Haemophilus ducreyi
- Granuloma inguinale - Calymmatobacteria granulomatis
2
Q
What are some STIs caused by viruses?
A
Ano-genital herpes - herpes simplex virus (HSV) type 1 and 2
Others (FYI)
Ano-genital warts - human papillomavirus (HPV)
Viral Hepatitis - Hepatitis A, B, C virus
AIDS/HIV infection - human immunodeficiency virus (HIV) type 1 and 2
Molluscum contagiosum - molluscum contagiosum virus
3
Q
What are some STIs caused by fungi? FYI
A
Vaginal candidiasis - candida albicans
4
Q
What are some STIs caused by parasites? FYI
A
Scabies - Sarcoptes scabiei
Pediculosis pubis - Phthirus pubis (public lice)
5
Q
What is a key local legislation regarding STIs in SG?
A
- STIs* are legally notifiable (within 72h of diagnosis) for monitoring and evaluating national control programs
- Partner notification is mandatory in HIV/AIDs
*Gonorrhoea, non-gonococcal urethritis, syphilis, chlamydia, genital herpes, HIV/ AIDS, Viral Hepatitis
6
Q
How can STIs be transmitted?
A
Mainly by sexual contact
- Direct contact of broken skin with open sores, blood or genital discharge
- Receiving contaminated blood
- From an infected mother to her child during:
Pregnancy (eg syphilis, HIV) or
Childbirth (eg chlamydia, gonorrhea, HSV) or
Breastfeeding (eg HIV)
7
Q
Can STIs be contracted through kissing?
A
Dry kissing is generally safe. Some STIs can be transmitted through deep, wet kissing. Syphilis, gonorrhoea, chlamydia and herpes may be present in the mouth/throat of infected persons.
However, STIs are not commonly transmitted through kissing.
8
Q
Can a person be infected with more than one STI?
A
Yes, this is possible and not uncommon. This is why it is always important to be tested for other STIs if you have already been diagnosed with one.
9
Q
Can someone inherit an STI from his or her parents,
i.e. is it a genetic disease?
A
STIs are acquired infections; they are not inherited. However, mothers with STIs can pass on their infection to the baby during pregnancy, delivery or breastfeeding. Early treatment of an infected pregnant mother can prevent infection in her baby.
10
Q
What are the risk factors for STIs?
A
- Unprotected sexual intercourse
- Those with multiple sexual partners are more likely to
acquire and transmit STI - Those with sexual contact with people who have
multiple sexual partners - MSM (gay sex)
- Prostitution (CSW)
- Illicit drug use*
*as STI can be transmitted via blood and affected cognition due to drugs -> increased risky behavior
11
Q
How can an individual prevent STIs?
A
- Abstinence and reduction of number of sexual partners
- Barrier contraceptive methods, when used correctly
- Avoid drug abuse and sharing needles
- Pre-exposure vaccination i.e. HPV (Human papilloma virus), Hep B
- Post-exposure prophylaxis (HIV)
12
Q
Why is management and prevention of STIs important?
A
- To reduce related morbidity, progression to
complicated disease - To prevent HIV infection
- To prevent serious complications in women (main preventable cause of infertility and reduces cervical
cancer risk) - To protect the babies
13
Q
What is the causative organism of Gonorrhoea?
A
Neisseria gonorrhoeae (intracellular gram-negative diplococci)
14
Q
How can gonorrhoea be transmitted?
A
Sexual contact, mother-to-child during childbirth
15
Q
How is Gonorrhoea diagnosed?
A
Gram-stain of genital discharge, culture, PCR
16
Q
Are Gonorrhea infections limited to the genital area?
A
No. Can infect various sites Urethritis Cervicitis Proctitis Pharyngitis Conjunctivitis Disseminated
17
Q
What are some symptoms of a gonorrhoea infection?
A
Purulent urethral/vaginal discharge, dysuria,
urinary frequency
Patients can be asymptomatic as well
18
Q
What are some complications of an untreated Gonorrhoea infection?
A
Males – epididymitis, prostatitis, urethral stricture,
disseminated* disease
Females – Pelvic inflammatory disease, ectopic
pregnancy, infertility, disseminated* disease
*Disseminated – skin lesions, tenosynovitis,
monoarticular arthritis.
19
Q
Are FQs used in the tx of Gonorrhoea?
Neisseria gonorrhoeae (intracellular gram-negative diplococci)
A
No. High local resistance to FQs
20
Q
What is the abx tx strategy when it comes to Gonorrhoea?
A
Dual Antibiotics Therapy
- Slows emergence of resistance and
- Improves treatment efficacy
- Also treats Chlamydia trachomatis, a usual co-infection with uncomplicated gonococcal infections
21
Q
What is the 1st line tx for Gonorrhoea?
A
IM ceftriaxone 250mg single dose + PO Azithromycin 1g single dose (concurrently)
Advantage of azithromycin
+ Single dose hence improve compliance
+ Substantially lower resistance compared to tetracycline
22
Q
What abx should we provide for a Gonorrhoea patient who is allergic to azithromycin?
A
IM ceftriaxone 250mg single dose + doxycycline 100mg bid x 7 days
*alternative + longer duration due to more resistance for doxy
23
Q
What abx should we provide for a Gonorrhoea patient who is allergic to penicillin and cephalosporins?
A
- IM spectinomycin 2g single dose + PO azithromycin 2g single dose OR
- IM gentamicin 240mg single dose + PO azithromycin 2g single dose
*spectinomycin and gentamicin not as effective as ceftriaxone –> larger azithro dose
24
Q
Is there a need to perform testing on the patient to confirm cure for Gonorrhoea?
A
Test of cure not required unless symptoms persist
25
What are the monitoring considerations for Gonorrhoea pts on abx tx?
Some GI side effects and allergies (monitor and come back to doctor if s/sx of allergies)
- low dose and IM --> shouldnt stay in body for too long --> nth much to monitor for
26
What is the causative organism for Chlamydia?
Chlamydia trachomatis
27
What are the clinical presentations for Chlamydia?
Presentation similar to gonorrhoea, perhaps milder*
(commonly co-infection tgt with gonorrhoea)
Purulent urethral/vaginal discharge, dysuria,
urinary frequency
*Patients can be asymptomatic as well, causing them to not get tx and develop complications
28
How is Chlamydia diagnosed?
Diagnosis using NAAT (PCR) or antigen detection
29
What are the complications of Chlamydia?
- Same as Gonorrhoea
Males – epididymitis, prostatitis, urethral stricture,
disseminated* disease
Females – Pelvic inflammatory disease, ectopic
pregnancy, infertility, disseminated* disease
*Disseminated – skin lesions, tenosynovitis,
monoarticular arthritis.
30
How can Chlamydia be transmitted?
Sexual contact, mother-to-child during childbirth
31
What is the 1st line tx for Chlamydia?
Azithromycin PO 1g single dose*
OR
Allergic to Azithromycin: Doxycycline 100mg PO BD x 7days
*Azithromycin as single dose is possible due to its prolonged serum and tissue half-life
32
What are some 2nd line tx for Chlamydia?
```
Erythromycin base 500mg PO QDS x 7days
OR
Erythromycin ethylsuccinate PO QDS x 7days
OR
Levofloxacin 500mg OD x 7days
OR
Ofloxacin 300mg PO BD x 7days
```
Erythromycin might be less efficacious than azithromycin or doxycycline.
Levofloxacin and ofloxacin are effective while other fluoroquinolone did not consistently eradicate chlamydial infection.
33
Is Test of cure necessary for Chlamydia?
Treatment is highly effective, test-of-cure is not required unless specific concerns (eg pregnancy, non-adherence) or symptoms persist*
*likely due to re-infection rather than tx failure
34
What is the organism that causes syphilis?
Treponema pallidum
35
How is syphilis transmitted?
Sexual transmission only when mucocutaneous syphilitic lesions are present.
Non-sexual:
- Transplacental from mother to child.
- Contaminated blood.
36
What are the 5 stages syphilis can present as?
1. Primary
2. Secondary
3. Latent
- early < 1 year from infection
- late > 1 year from infection
4. Tertiary
5. Neurosyphilis
37
Explain the primary stage of syphilis presentation in terms of timeline, site of infection and s/sx.
1. Timeline: Incubation period 10-90d (mean 21d). Heals spontaneously in 1-8wks.
2. Site of infection: External genitalia, perianal region, mouth, throat
3. S/sx: Single, painless, indurated lesion (chancre) --> erodes --> ulcerate --> heals; regional lymphadenopathy
38
Explain the secondary stage of syphilis presentation in terms of timeline, site of infection and s/sx.
1. Timeline: Develops 2-8wks after initial infection in untreated or inadequately treated indiv. Disappears in 4-10 wks if untreated.
2. Site of infection: Multisystem involvement due to hematogenous and lymphatic spread
3. S/sx: Rash (non-pruritis on palm and soles), mucocutaneous lesions, flulike symptoms, lymphadenopathy
39
Explain the Latent stages of syphilis presentation in terms of timeline, site of infection and s/sx.
1. Timeline: Develops 4-10 wks after secondary stage in untreated or inadequately treated individual
2. Site of infection: Possible Multisystem involvement
3. S/sx: Asymptomatic but serology positive
40
Explain the tertiary stage of syphilis presentation in terms of timeline, site of infection and s/sx.
1. Timeline: Develops in approx 30% of untreated or
inadequately treated individuals 10-30 yrs after initial
infection
2. Site of infection: Possible multisystem heart, eyes, bones, joint
3. S/sx: Gummatous lesions, impaired movement, Heart- aortic insufficiency
41
Explain the neurosyphilis stage of syphilis presentation in terms of timeline, site of infection and s/sx.
1. Timeline: Any stage of syphilis
2. Site of infection: CNS
3. S/sx: Eg: Cognitive dysfunction, motor or sensory deficits, ophthalmic or auditory symptoms, signs and symptoms of meningitis, stroke etc
42
What is the syphilis stage the patient is suffering from?
Single, painless, indurated lesion (chancre) in External genitalia and mouth
Primary stage
43
What is the syphilis stage the patient is suffering from?
Rash (non-pruritis on palm and soles), mucocutaneous lesions with flulike symptoms
Secondary stage
44
What is the syphilis stage the patient is suffering from?
Asymptomatic pt that recently has a positive serology test for syphilis, last had sexual intercourse 4 months ago (16 weeks), no prior hospitalization hx
Latent (early < 1 year)
45
What is the syphilis stage the patient is suffering from?
45 year old Patient PMH showed syphilis infection 23 years ago. Patient shared that he was unable to afford the medications. Presented at the clinic today with gummatous lesions on his neck and mouth, nurse noted impaired movement for patient.
Tertiary stage
46
How is syphilis diagnosed?
1. Darkfield microscopic exam of serous material from suspected lesion
2. Serology - Nontreponemal test + Treponemal test
47
Discuss the place in therapy for Darkfield microscopic exam in Syphilis.
+ Confirmatory
| + Good for early stage since treponemal serology may not be reactive early in disease
48
Discuss the place in therapy for Non-treponemal tests in Syphilis.
i. e. Uses nontreponemal antigen (cardiolipin) to detect treponemal antibodies
- Venereal Disease Research Laboratory (VDRL) slide test
- Rapid plasma reagin (RPR) card test
- Reports most dilute serum concentration with a positive reaction (eg result 1:16 positive means at 1:32 no reaction seen)
(+) Used as a tool to monitor response to treatment*
- Test titres usually declines after treatment and can become non-reactive with time
(-) Less specific, needs to be confirmed with a treponemal test
*larger ratio = larger organism burden
49
Are the VDRL and RPR Non-treponemal tests interchangeable?
VDRL/RPR are not interchangeable; need to use the same test for monitoring
50
Discuss the place in therapy for treponemal tests in Syphilis.
i.e. Uses treponemal antigen to detect treponemal
antibody
- Eg T. pallidum Haemaggluntination test (TPHA), T. pallidum passive particle agglutination assay (TPPA)
(+) Treponemal tests are more sensitive and specific than nontreponemal tests, used as confirmatory tests.
(-) May remain reactive for life, hence not for monitoring response to treatment
51
How can we monitor therapeutic response in Syphilis?
1. Primary / secondary: Quantitative VDRL or RPR at 6 and 12 months
- Treatment success = decrease of VDRL or RPR titre by at least fourfold (eg 1:16 to 1:4)
2. Latent syphilis: 6, 12 and 24 months
3. Neurosyphilis: CSF examination every 6 month until CSF normal
4. Side effects, ADRs of drugs
52
What is something to note when initiating Syphilis tx?
The Jarisch-Herxheimer reaction is an acute febrile reaction frequently accompanied by headache, myalgia, and other symptoms that usually occur within the first 24 hours after any therapy for syphilis.
- Antipyretics will help but not prevent.
53
What constitutes tx failure for Syphilis and what is the appropriate response?
- Show sign and symptoms of disease or
- Failure to decrease VDRL or RPR titre by fourfold OR incr (1:4 to 1:16)
Retreat and re-evaluate for unrecognized neurosyphilis
54
How should the Syphilis patient's sexual partners be managed and counselled upon diagnosis?
- Sexual partners should be evaluated for STIs and treated if positive.
- Abstinence should be practiced until 7 days after a single-dose regimen or after completion of a 7-day regimen and resolution of symptoms, if present.
- Patients and their sex partners should be counseled that re-infections can occur as there is no permanent
immunity conferred by a previous infection(s).
55
What is the virus characteristics of Herpes simplex virus?
* Enveloped, double stranded DNA virus
* Replicate in host cell nucleus
* Persist indefinitely (life-long) in infected hosts (latent infection)
* Periodic reactivations, especially in immunocompromised hosts
56
Compare HSV1 vs HSV2
HSV1: mainly young children, transmitted via contact (often saliva), may be managed with topical acyclovir (modest benefit) --> cold sores/oral lesions
HSV2: Young adults, sexual transmission --> gential herpes
Both managed using PO acyclovir/valacyclovir
57
What are some stimuli for reactivation of herpes infections?
- Stimuli such as fever, menstruation, sunlight, stress etc can reactivate the virus
*Reactivation may be clinically asymptomatic, or it may
produce life-threatening disease
58
What are the 2 types of disease caused by Varicella Zoster Virus (VZV) aka HSV-3?
- Primary VZV infection results in the diffuse vesicular rash of varicella, or chickenpox.
- Reactivation of latent VZV typically results in a localized skin infection known as herpes zoster, or shingles
59
How does Varicella (chicken pox) present?
- Fever starts 1 - 2 days before the rash appears and lasts for 4 - 5 days. It usually abates once the rash has
completely appeared.
- Groups of new lesions appearing in crops over 4 to 7 days.
- Pox/rash may be seen in all stages - macules, papules, vesicles, pustules and scabs. The scalp, face, limbs and trunk are all involved with relative sparing of palms and soles.
60
What is the severity of Varicella (chicken pox)?
Benign self-limiting illness
| - Can be a severe disease in adolescents, adults, and immunosuppressed or immunocompromised individuals of any age.
61
What are major risk factors for herpes zoster (Shingles)?
Increasing age and immunosuppression
62
How does Shingles present?
- The rash begins as papules, which evolve into vesicles and then pustules. New lesions appear over a period of 3 to 5 days, usually dries with crusting in 7 to 10 days.
- The rash is often preceded by tingling, itching, or pain (or a combination of these) for 2 to 3 days, and these symptoms can be continuous or episodic.
- Post-herpetic neuralgia occurs in 10-50% of patients. It is a pain persisting after the rash has resolved . The pain may persist for many months or even years
63
What are the tx options for varicella/shingles?
Acyclovir dose:
- PO 800mg 5 times daily x 7 days
Valacyclovir dose:
- PO 1g 3 times daily x 7 days
Prophylaxis: chicken pox/shingles vaccines
Start within 24 - 48 hours of rash to reduce duration and severity of symptoms
64
Which of the following are considered STIs?
- HSV-2 causes genital herpes, considered as STI (sexually transmitted infections)
- HSV-1 commonly causes Herpes labialis (cold sore), NOT a STI
- VZV causes varicella (chicken pox) and herpes zoster (shingles), Not a STI
65
What are the 5 cycles of HSV infection?
1. Primary mucocutaneous infection
2. Infection of the nerve ganglia
3. Establishment of latency
4. Reactivation
5. Recurrent outbreaks/flairs.
66
How is HSV-2 transmitted?
Transmission via transfer of body fluids and intimate skin to- skin contact
67
What is the pathogenesis and etiology of HSV-2?
Incubation 2-14 days (mean 4 days)
Vesicles develop over 7-10 days, heal in 2-4 weeks
Intermittent viral shedding from epithelial cells
Chronic and life-long viral infection
*May not be symptomatic while shedding and transmission occurs
68
What are the s/sx of genital herpes?
- classical painful multiple vesicular or ulcerative lesions
- Also local itching, pain, tender inguinal adenopathy
(lymphadenopathy)
- Flu-like symptoms (e.g., fever, headache, malaise)
during first few days after appearance of lesions.
- Prodromal symptoms like mild burning, itching or
tingling are seen in approximately 50% of patients prior to appearance of recurrent lesions (in recurrent
disease).
*Symptoms less severe in recurrent disease (less
lesions, heal faster, milder symptoms)
69
How is genital herpes diagnosed?
1. Patient history (previous lesion/ sexual contact with similar lesions)
2. Presentation / symptoms
3. Virologic tests (Viral cell culture* and PCR for HSV DNA preferred)
4. Serologic tests
*Uncommon
70
What is the place in therapy for serologic tests for genital herpes?
- Antibodies to HSV develop during the first several weeks after infection and persist indefinitely.
- Serology is not useful for first episode infection as it takes between 6 and 8 weeks for serological detection following a first episode
71
What is the management goal of genital herpes tx?
Relieve symptoms, shorten clinical course, prevent complications and recurrences, decrease transmission
*Not to achieve cure, herpes is a chronic lifelong disease (with latency in neuroganglia)
72
What are some supportive care measures for genital herpes?
Warm saline bath relieves discomfort
Good genital hygiene* to prevent superinfection
Counseling regarding natural history
*infection can be itchy --> excoriation can lead to infection
73
What is the place in therapy for antiviral tx (Oral acyclovir and valacyclovir) in genital herpes?
- Reduce viral shedding by 7 days
- Reduce duration of symptoms by 2 days and
- Reduce time to healing of 1st episode by 4 days
- Effective only while pt is taking drug
- Max benefit when initiated within 72h at earliest stage of disease
74
What is the place in therapy for topical antiviral tx in genital herpes?
Topical antiviral offers minimal clinical benefit, can cause local irritation hence its use is discouraged
75
Is there any difference between choosing acyclovir and valacyclovir?
Valacyclovir is a pro-drug of acyclovir with higher bioavailability (may allow less frequent dosing)
- Comparable efficacy, choice dependent on pt compliance and cost
76
What is the 1st line tx for a pt with their 1st episode of genital herpes?
Either Acyclovir or Valacyclovir:
1. Acyclovir
- 400mg TID for 7–10 days OR 200mg 5x/day for 7–10 days
- IV 5-10 mg/kg q8h x 2-7 days, complete with PO for a total 10 days (for severe disease)
2. Valacyclovir
- 1g BID for 7–10 days
77
What are some counselling points for valacyclovir/acyclovir?
Take without regards to food, after food if GI upset. SE: Malaise, headache, nausea, vomiting, diarrhoea.
IMPT: Maintain adequate hydration to prevent crystallization in renal tubules.
Valacyclovir main SE: Headache
78
What should we do if healing in incomplete after 10 days of acyclovir/valacyclovir therapy for an initial episode of genital herpes?
Treatment can be extended if healing is incomplete after 10 days of therapy.
79
What is the prevalence of recurrent genital herpes?
- Almost all persons with symptomatic first episode genital herpes infection will experience recurrent flares (reactivations)
- Patients have a median of 4 recurrences the year after their first symptomatic episode
80
What are the therapy options for recurrent genital herpes?
Antiviral Chronic Suppressive or Episodic Therapy
81
What are reasons to recommend the Chronic suppressive antiviral therapy for recurrent genital herpes?
+ Reduces the frequency of recurrences by 70%–80% in patients who have frequent recurrences (i.e. >6 recurrences per year)
+ Many patients report no symptomatic outbreaks (hence improved quality of life)
+ Established long term safety & efficacy (acyclovir 6 yrs, valaciclovir 1yr)
+ Decr risk of transmission* (in combination with
consistent condom use and abstinence during
recurrences)
*big benefit as herpes transmission can still occur even while pt is asymptomatic (viral shedding from epithelial cells)
82
What are reasons to NOT recommend the Chronic suppressive antiviral therapy for recurrent genital herpes?
- Cost
- Compliance*
- Adverse drug reactions
- Recurrence occurs at baseline frequency when discontinued
- resistance** reported but association with chronic suppressive therapy uncertain
* depending on regimen, may need to take more than OD
* *reported in up to 5% HIV pts but rare
83
What are the options for chronic suppressive antiviral therapy for recurrent genital herpes?
```
Acyclovir 400mg PO BD
OR
Valacyclovir 500mg PO OD
OR
Valacyclovir 1g PO OD*
```
*For pts w frequent recurrences (10 or more episodes annually)
84
What is the duration for chronic suppressive antiviral therapy for recurrent genital herpes?
Duration is patient- and disease- course dependent.
Patients with complicated disease course eg disseminated disease (encephalitis, meningitis, keratitis), usually in immunocompromised hosts, may need indefinite suppression.
85
What are reasons to recommend episodic antiviral therapy for recurrent genital herpes?
+ Shorten duration and severity of symptoms
+ Less costly vs chronic suppression
+ Patient more likely to be compliant
86
What are reasons to NOT recommend episodic antiviral therapy for recurrent genital herpes?
- Requires initiation of therapy within 1 day of lesion onset or during the prodrome that precedes some outbreaks
- Does not reduce risk of transmission
87
What are the options for episodic antiviral therapy for recurrent genital herpes?
```
Acyclovir 400mg PO TDS x 5days
OR
Acyclovir 800mg PO BD x 5days
OR
Acyclovir 800mg PO TDS x 2days
OR
Valacyclovir 500mg PO BD x 3days
OR
Valacyclovir 1g PO OD x 5days
```
88
What are some counselling pointers for persons with HSV infection?
- Educate concerning the natural history of the disease
- Encourage to inform their current and future sex partners
- Sexual transmission of HSV can occur during asymptomatic periods.
- All persons with genital herpes should remain abstinent from sexual activity with uninfected partners when lesions or prodromal symptoms are present.
- The risk of HSV sexual transmission can be decreased by the daily use of valacyclovir or acyclovir by the infected person.
- Recent studies indicate that latex condoms, when used consistently and correctly, might reduce the risk for genital herpes transmission.
- Risk for neonatal HSV infection
- Increased risk for HIV acquisition
89
What are the pointers to discuss when talking about the natural history of genital herpes?
It is a chronic, lifelong disease
Asymptomatic shedding can lead to transmission
There will be recurrent episodes
90
What are pointers in management of sex partner in genital herpes?
- Symptomatic sex partners should be evaluated and
treated in the same manner as patients who have genital lesions.
- Asymptomatic sex partners of patients who have genital herpes should be questioned concerning histories of genital lesions and offered type-specific serologic testing* for HSV infection.
* i.e. test for HSV-1 or HSV-2 antibodies
- HSV-1 not likely to be genital herpes
- HSV-2 more likely to be genital herpes
