STD Flashcards
Mode of transmission of STDs
- Sexual contact
- Direct contact of broken skin with open sores/ blood/ genital discharge
- Receiving contaminated blood
- Mother -> Child (Via placenta: HIV, Syphillis) / (Breastfeeding: HIV) / (Childbirth: Chlamydia, gonorrhea, HSV)
Risk factors for STDs
- Unprotected sexual intercourse
- No. of sexual partners
- MSM
- Prostitution (CSW)
- Illicit drug use
Prevention methods for STDs
- Abstinence & no. of sexual partners
- barrier contraceptive methods
- avoid drug use & sharing of needles
- pre-exposure vaccination (HPV, Hep A & B)
- Pre & post exposure prophylaxis
Importance of management of STDs
- Reduce related morbidity, progression to complicated disease (Can be lifelong; affect QOL)
- Prevent HIV Infection
- Prevent serious complications
- -> Main preventable cause of infertility in women
- Reduced no. of women with cervical cancer
- Protect babies
Gonorrhoea (Caused by which bacteria/Transmission/Diagnosis/Sites infected)
Presentation of Gonorrhoea
Male
- Purulent urethral discharge, dysuria, urinary frequency
Female
- Mucopurulent vaginal discharge, dysuria, urinary frequency
Note: can be asymptomatic
Complications of Gonorrhoea (if untreated)
Males:
- Epididymitis, prostatitis, urethral stricture
Females:
- Ectopic pregnancy, pelvic inflmm disease, infertility
Both:
Disseminated disease - Skin lesions, tenosynovitis, monoarticular arthritis
Management of Uncomplicated Urogenital Gonorrhoea
1) Ceftriaxone: 500mg IM single dose (For > 150kg: 1g)
2) Gentamicin 240mg IM single dose +
Azithromycin 2g PO single dose
3) Cefixime 800mg PO single dose
If gonorrhoea + chlamydia:
1) Ceftriaxone: 500mg IM single dose
(For > 150kg: 1g) +
Doxycycline 100mg PO BD x 7days
2) Cefixime 800mg PO single dose +
Doxycycline 100mg PO BD x 7days
Management of sexual partners (Gonorrhea/Chlamydia)
1) Sex partners in last 60 days should be evaluated & treated (If last exposure > 60 days: Most recent partner to be treated)
2) Persons treated for ___ should abstain from sexual activity for 7 days after receiving treatment (or till symptoms resolve)
3) Abstain from sexual activity until all sexual partners have been treated
Management of Chlamydia
1) Doxycycline 100mg PO BD x 7 days
Alternatives:
1) Azithromycin 1g PO single dose (can be used if adherence is a concern)
2) Levofloxacin 500mg PO OD x 7 days
Management of Chlamydia
1) Doxycycline 100mg PO BD x 7 days
Alternatives:
1) Azithromycin 1g PO single dose (can be used if adherence is a concern)
2) Levofloxacin 500mg PO OD x 7 days
Serological tests for Syphilis
1) Treponemal test
- Use trepenomal antigen to detect trepenomal antibody
- More sensitive & specific, used for DIAGNOSIS but not for monitoring as it may remain active for life
2) Nontrepenomal test
- Use nontrepenomal antigen to detect trepenomal antibodies
- Result reported in quantitative VDRL/RPR test: Most dilute [serum] with a positive reaction
- Less specific, used for MONITORING
Management of Syphilis
Pri/Sec/Early latent stage (< 1yr duration):
1) IM Benzathine Pen G 2.4mil units x 1 dose
2) PO Doxycycline 100mg BD x 14days
- Take with glass of H20 & remain upright for 30mins
Late latent (> 1yr duration)/ Tertiary Stage:
1) IM Benzathine Pen G 2.4mil units x 1/week x 3doses
2) PO Doxycycline 100mg BD x 28days
Neurosyphilis:
1) IV Crystalline Pen G 3-4mil units Q4h/ 18-24 mil units a day as continuous infusion x 10-14days
2) IM Procaine Pen G 2.4 mil units +
PO Probenicid 500mg QID x 10-14days
Management of Syphilis
Pri/Sec/Early latent stage (< 1yr duration):
1) IM Benzathine Pen G 2.4mil units x 1 dose
2) PO Doxycycline 100mg BD x 14days
- Take with glass of H20 & remain upright for 30mins
Late latent (> 1yr duration)/ Tertiary Stage:
1) IM Benzathine Pen G 2.4mil units x 1/week x 3doses
2) PO Doxycycline 100mg BD x 28days
Neurosyphilis:
1) IV Crystalline Pen G 3-4mil units Q4h/ 18-24 mil units a day as continuous infusion x 10-14days
2) IM Procaine Pen G 2.4 mil units daily +
PO Probenicid 500mg QID x 10-14days
3) IV/IM Ceftriaxone 2g daily x 10-14days
What is the Jarisch-Herxheimer reaction?
An acute febrile reaction accompanied by HA, myalgia & other symptoms that occur within 24hrs after any therapy for syphilis
Monitoring of syphilis treatment
Decrease of VDRL/RPR titre by at least fourfold
Latent syphilis: 6, 12 & 24 mths
Neurosyphilis: CSF examination every 6 month until CSF
normal
Treatment failure @ 6mths:
- Shows signs & symptoms of disease
- Failure to decrease VDRL/RPR titre by fourfold or increased
- Retreat & re-evaluate for unrecognised syphilis
How is genital herpes transmitted?
Bodily fluids/ intimate skin-to-skin contact
Genital herpes (Virus, cycle of HSV infection)
Virus: HSV-1 & HSV-2 Cycle: - Pri mucocutaneous infection - Infection of the nerve ganglia - Establishment of latency - Reactivation - Recurrent outbreak/flairs
- Vesicles develop over 7-10days, heal in 2-4 weeks
- Intermittent viral shedding from epithelial cells
- Chronic & lifelong viral infection
Diagnosis of genital herpes
- Patient history (Previous lesion/ sexual contact with person with lesions)
- Classic painful multiple vesicular or ulcerative lesions
- Local itching, pain, tender inguinal lymphadenopathy
- Mild burning, itching or tingling prior to appearance of recurrent lesions
- Flu-like symptoms
Tests:
1) Virologic tests (Send fluid from genital lesions)
2) Type-specific serologic tests (Send blood to look for Ab)
- Presence of HSV-2 antibody
Management of genital herpes
NO CURE!!!
- Relieve symptoms, shorten clinical course, prevent complications & recurrences, decrease transmission
Supportive care:
- Warm saline bath to relieve discomfort
- Good genital hygiene
- Counselling regarding natural history
Antiviral treatment for genital herpes
1) Acyclovir 400mg TDS X 7-10days or
IV 5-10mg/kg Q8H x 2-7days, complete
with PO for a total of 10 days
2) Valacyclovir 1g BD x 7-10days
Chronic suppressive therapy vs Episodic therapy
Chronic suppressive therapy Decreases transmission:
- Red frequency of recurrence by 70-80%
- Many pts report no symptomatic outbreaks
- Improve QOL
- Long term efficacy & safety
BUT cost & compliance issues
Episodic therapy
- Shorten duration & severity of symptoms
- Less costly & btr compliance
BUT does not reduce risk of transmission & requires initiation of therapy within 1 day of lesion onset/ during prodome that precedes some outbreaks
Chronic suppressive therapy antiviral regimen
1) Acyclovir 400mg BD
2) Valacyclovir 500MG OD (may be < effective)
3) Valacyclovir 1g OD
4) Famciclovir 250mg BD
Episodic therapy antiviral regimen
1) Acyclovir 800mg BD x 5days OR
Acyclovir 800mg TDS x 2days
2) Valacyclovir 500mg BD x 3days OR
Valacyclovir 1g OD x 5 days
3) Famciclovir 1g BD x 1day
Famciclovir 500mg OD once, followed by 250mg BD x
2 days
Famciclovir 125mg BD x 3days
ART combinations for HIV patients
2 NRTIs + 1 INSTI:
1) Tenofovir + Emtricitabine + Dolutegravir
2) Tenofovir + Emtricitabine + Bictegravir
3) Abacavir + Lamivudine + Dolutegravir
1 NRTI + 1 INSTI (Cannot if HIV RNA > 500,000 copies/mL or HBV coinfection or ART is to be started before results of HIV genotypic resistance testing or HBV testing are available):
1) Emtricitabine + Dolutegravir
NRTIs (Examples, Advantages, Disadvantages, ADE, DDI)
Eg: Tenofovir, Emtricitabine, Abacavir, Lamoivudine, Zidovudine
- Renal elimination (Abacavir no need renal adj)
- Adverse effect related to mitochondrial toxicity (Lactic acidosis, hepatic steatosis, lipoatrophy, Zidovudine**)
Emtricitabine & Lamoivudine: Minimal toxicity
Tenofovir: Decrease in bone marrow density, renal impairment
Abacavir: Hypersensitivity (HLA-B*5701), Associated with MI; Not in CVS risk patients
Zidovudine: Bone marrow supression
INSTIs (Examples, Advantages, Disadvantages, ADE, DDI)
Eg: Bictegravir, Dolutegravir, Raltegravir, Elvitegravir
Advantages:
- Good virologic effectiveness
- High genetic barrier to resistance
- Generally well tolerated
Disadvantages:
- Weight gain, diarrhoea, nausea, HA
- Depression & sucidality (Pri in patients with pre-existing psychiatric conditions)
- DDI: Bioavailability lowered by concurrent polyvalent cations
- All CYP3A4 substrates EXCEPTS Raltegravir
Dolutegravir & Bictegravir: Increase in serum Cr
Raltegravir: Pyrexia, Increase in creatine kinase elevation (Rhabdomyolysis)
NNRTIs (Examples, Advantages, Disadvantages, ADE, DDI)
Eg. Efavirenz, Rilpivirine (preferred)
Advantages:
- Long t 1/2
- Less metabolic toxicity
Disadvantages:
- Low genetic barrier to resistance
- Skin rash, SJS (Efavirenz)
- Potential for CYP450 DDI
- QTc prolongation
Efavirenz: Neuropsychiatric SE, SJS, Increase in LDL-C &
triglycerides, hepatotoxicity
Rilvipirine: Depression, HA
PIs (Examples, Advantages, Disadvantages, ADE, DDI)
Advantages:
- High genetic barrier to resistance
- PI resistance < common
Disadvantage:
- Dyslipidaemia, insulin resistance, N/V, Diarrhoea, liver toxicity, Fat maldistribution, Increased risk of osteopenia/osteoporosis
- CYP3A4 inhibitors & substrates
Ritonavir:
- Potent CYP3A4, 2D6 inhibitor, freq combined with other PI to “boost” their levels
- Paresthesia (Numbness of extremeties), taste perversion
Darunavir
- Good GI tolerability, less lipid effects
- Skin rash, SJS concern
Atazanavir:
- Good GI tolerability, less lipid effects
- hyperbilirubinemia, QTc prolongation, skin rash
Fusion Inhibitor (Examples, Advantages, Disadvantages, ADE, DDI)
Enfuvirtide
- Injection site reaction
- Increased bacterial pneumonia
CCR5 Antagonist (Examples, Advantages, Disadvantages, ADE, DDI)
Maraviroc
- Used only in ppl whose HIV strain use CCR5 receptor to enter CD4 cells
- Ab pain, cough, dizzines, muscoskeletal symptoms, pyrexia, rash, URTI, hepatotoxicity, orthostatic hypotension
