Management of STIs Flashcards
How does HIV weaken the immune system?
- HIV attacks and destroys the infection-fighting CD4 T cells of the immune system
- Loss of CD4 T cells weakens the immune system, ultimately leading to Acquired Immunodeficiency Syndrome (AIDS)
How is HIV transmitted?
HIV is transmitted from one person to another through specific body fluids eg blood, semen, genital fluids and breast milk
→ Having unprotected sexual intercourse with an infected person
→ Sharing infected syringes and needles eg between IV drug users
→ Mother-to-child transmission during pregnancy, at birth or through breastfeeding
→ Transfusion w contaminated blood and blood products
Who should be tested for HIV?
- Intravenous drug users
- Persons who have unprotected sex with multiple partners
- Men who have sexual intercourse with other men
- Commercial sex workers
- Persons treated for STDs
- Recipients of multiple blood transfusion
- Persons who have been sexually assaulted
- Pregnant women (mandatory in SG to check, to prevent mother-to-child transmission)
How is HIV diagnosed?
- Serum antibody detection – HIV Immunoassay Antibody tests, Western Blot
- HIV RNA detection/quantification (viral load) – PCR done to amplify nucleic acid amount to quantify
Why is CD4 count taken for HIV patients?
Representation of immune system status
→ Used to determine urgency for initiating antiretroviral therapy
→ Used to assess response to antiretroviral therapy
→ Used to assess the need for initiating or discontinuing prophylaxis for opportunistic infections
When should CD4 count be taken?
At baseline and
Every 3-6 months after treatment initiation and
Every 12 months after achieving adequate response
When should viral load be taken?
Before initiation of therapy and
Within 2-4 weeks (not later than 8 weeks) after treatment initiation or modification;
thereafter every 4-8 weeks until viral load suppressed
What are the recommended ART options for treatment-naive HIV?
- Tenofovir + Emtricitabine + Bictegravir
- Tenofovir + Emtricitabine + Dolutegravir
- Abacavir + Lamivudine + Dolutegravir
What would preclude a patient from taking a HIV treatment of 1 NRTI + 1 INSTI only?
- HIV RNA >500,000 copies/ml
- HBV coinfection (need 2 active antivirals for Tx)
- In whom ART is to be started before the results of HIV genotypic resistance testing or HBV testing are available
List the names of the Nucleoside Reverse Transcriptase Inhibitors
Tenofovir, Emtricitabine, Abacavir, Lamivudine, Zidovudine
What are the adverse effects of lamivudine?
minimal toxicity, N/V/D
What are the adverse effects associated w the whole class of NRTIs?
- Lactic acidosis and hepatic steatosis (fatty infiltrate)
- Lipoatrophy (loss of fat)
What are the adverse effects of emtricitabine?
minimal toxicity, hyperpigmentation, nausea, diarrhoea
What are the adverse effects of tenofovir?
N/V/D, can cause renal impairment, decrease in bone mineral density
What are the adverse effects of abacavir?
N/V/D, hypersensitivity reaction in patients w HLA-B*5701 (rash, fever, malaise or fatigue, sore throat, cough, SOB)
- Testing for HLA-B*5701 recommended before initiation
- Not to be used in high CV risk patients as well – association w myocardial infarction
What are the adverse effects of zidovudine?
N/V/D, myopathy, bone marrow suppression causing anemia or neutropenia
List the Integrase Strand Transfer Inhibitors.
Bictegravir, Dolutegravir, Raltegravir, Elvitegravir
What are the adverse reactions associated with the class of INSTIs?
Weight gain, diarrhoea, nausea, headache
Depression and suicidality rare, mainly w preexisting psychiatric conditions
What are the adverse effects of bictegravir?
increased SCr
What are the adverse effects of dolutegravir?
increased SCr
List the Non-Nucleoside Reverse Transcriptase Inhibitors.
Efavirenz, Rilpivirine
What are the adverse effects associatedd with efavirenz?
rash, hyperlipidemia, neuropsychiatric SE (dizziness, depression, insomnia, abnormal dreams) hepatotoxicity
What are the adverse effects of rilpivirine?
depression, headache
List the Protease Inhibitors.
Ritonavir, Lopinavir, Atazanavir, Darunavir, Fosamprenavir
What are the adverse reactions to the class of protease inhibitors?
o Metabolic complications (dyslipidemia, insulin resistance)
o GI SE – N/V/D
o Liver toxicity (esp w chronic Hepatitis B or C)
o CYP3A4 inhibitors and substrates: potential for drug interactions
o Morphologic complications: fat maldistribution (Lipohypertrophy)
o Increased risk of osteopenia/osteoporosis
List the fusion inhibitors.
Enfuviritide
What are the adverse effects associated w enfuviritide?
injection site reaction, rare hypersensitivity reaction, increased bacterial pneumonia
What is maraviroc?
CCR5 antagonist
What are the adverse effects of maraviroc?
abdominal pain, cough, dizziness, musculoskeletal symptoms, fever, rash, URTI, hepatotoxicity, orthostatic hypotension
What is the pathogen that gonorrhea is caused by?
Neisseria gonorrhoeae
How is gonorrhea transmitted?
Transmitted via sexual contact and from mother-to-child during childbirth
How is gonorrhea diagnosed?
gram stain of genital discharge, culture, nucleic acid amplification test
What are the symptoms of gonorrhea?
Males – purulent urethral discharge
Females – mucopurulent vaginal discharge
Both – dysuria, increased urinary frequency
What is the first line treatment for gonorrhea?
Single dose of IM Ceftriaxone
<150kg: 500mg
>150kg: 1g
Add PO doxycycline 100mg BD for 7/7 if chlamydia has not been excluded
What is the non-beta lactam option for treating gonorrhea?
IM Gentamicin 240mg as a single dose +
PO Azithromycin 2g as a single dose
(Azithromycin provides chlamydia cover)
How should the sex partners of a gonorrhea patient be handled?
- Sex partners in the last 60 days should be evaluated and treated
- If last sexual exposure >60 days, the most recent partner should be treated
- To minimise transmission, patients should abstain from sexual activity for 7 days after Tx ends or symptom resolution, whichever is later
- To minimise risk for reinfection, patients should also abstain from sexual activity until all their sexual partners have been treated
What is the pathogen that chlamydia is caused by?
Chlamydia trachomatis
How does chlamydia present?
Similar to gonorrhea:
Males – purulent urethral discharge
Females – mucopurulent vaginal discharge
Both – dysuria, increased urinary frequency
Therefore, chlamydia and gonorrhea commonly treated tgt, until confirmation of STI identity (eg nucleic acid amplification results)
What is the first line option for chlamydia treatment?
PO Doxycycline 100mg BD x 7/7
What are the alternative options for chlamydia treatment?
PO Azithromycin 1g as a single dose OR
PO Levofloxacin 500mg OD x 7/7
How should the partners of a chlamydia patient be handled?
Sex partners in the last 60 days should be evaluated and treated
- If last sexual exposure >60 days, the most recent partner should be treated
- To minimise transmission, patients should abstain from sexual activity for 7 days after Tx ends or symptom resolution, whichever is later
- To minimise risk for reinfection, patients should also abstain from sexual activity until all their sexual partners have been treated
What is the pathogen that causes syphilis?
Treponema pallidum
How is syphilis transmitted?
Transmission via sexual contact or from mother-to-child (transplacental during pregnancy
What are the tests used to diagnose syphilis?
Darkfield microscopy of exudates from lesions
Treponemal and non-treponemal tests
What are treponemal tests used for?
Used for confirmation of syphilis
Not used for monitoring response to syphilis treatment
What are non-treponemal tests used for?
Used to monitor response to treatment
What are the treatment options for primary, secondary, or early latent syphilis infections?
IM Benzathine Penicillin G 2.4 million units x 1 dose
PO Doxycycline 100g BD x 14/7
What are the treatment options for late latent syphilis infection?
IM Benzathine Penicillin G 2.4 million units once a week x 3 doses
PO Doxycycline 100g BD x 28/7
What are the treatment options for neurosyphilis?
IV Crystalline Penicillin G 3-4 million units Q4H x 10-14/7 OR
IV Crystalline Penicillin G 18-24 million units/day as continuous infusion x 10-14/7 OR
IM Procaine Penicillin G 2.4 million units OD
+ PO Probenecid 500mg OD for 10-14/7
What is the Jarisch-Herxheimer reaction?
Acute febrile reaction frequently accompanied by headache, myalgia, and other symptoms
that usually occur within the first 24 hours after ANY therapy for syphilis
How should response to syphilis treatment be monitored?
Primary/Secondary/Latent Syphilis: Quantitative VDRL or RPR at 3, 6, 12, 18, 24 months (success: decrease of VDRL or RPR titre by at least 4x)
Neurosyphilis: CSF examination Q6/12 until CSF normal
How should the sexual partners of syphilis patients be handled?
- All at risk sexual partners should be evaluated for STIs and treated if tested positive
- Persons who receive syphilis treatment must abstain from sexual contact w new sexual partners until the syphilis lesions are completely healed – best to get this checked by doctor for the green light
What is the pathogen that causes genital herpes?
Herpes simplex virus (HSV-1 & HSV-2)
Most recurrent genital herpes are caused by HSV-2
How does HSV infection develop?
primary mucocutaneous infection → infection of nerve ganglia → establishment of latency → reactivation → recurrent outbreaks/flairs
How are genital herpes transmitted?
transfer of body fluids and intimate skin-to-skin contact
How does genital herpes present?
→ Classical painful multiple vesicular or ulcerative lesions
→ Local itching, pain, tender inguinal lymphadenopathy
→ Flu-like symptoms (eg fever, headache, malaise) during 1st few days after appearance of lesions
→ Prodromal symptoms like mild burning, itching or tingling are seen in ~50% of patients prior to appearance of recurrent lesions (in recurrent disease)
→ Symptoms less severe in recurrent disease – have antibodies to fight off symptoms alr
How should genital herpes be diagnosed?
Virologic Tests – viral cell culture and nucleic acid amplification test for HSV DNA
Type-Specific Serologic Tests
→ Antibodies to HSV develop during first several weeks of infection and persist indefinitely
→ Not useful for first episode infection as it takes 6-8 weeks for detection after 1st episode
→ Presence of HSV-2 antibody implies anogenital infection – HSV-2 mostly acquired by sexual contact
How can patients manage the symptoms of genital herpes?
→ Warm saline bath to relieve discomfort
→ Symptom management – painkillers, anti-itch
→ Good genital hygiene to prevent superinfection
What are the treatment options for the first episode of genital herpes?
Acyclovir PO 400mg TDS x 7-10 days
OR
Valacyclovir PO 1g BD x 7-10 days
What are the treatment options for severe genital herpes?
IV Acyclovir 5-10mg/kg Q8H x 2-7 days,
complete w PO for total of 10 days
What are the counselling points for acyclovir and valacyclovir?
Take w/o regards to food (can take after food if GI upset)
SE: Malaise, headache, N/V/D
Maintain adequate hydration to prevent crystallisation in renal tubules
What are the regimens for chronic suppressive therapy of recurrent genital herpes?
- PO Acyclovir 400mg BD
- PO Valacyclovir 500mg OD
What are the regimens for episodic therapy of recurrent genital herpes?
- PO Acyclovir 800mg BD x 5/7
- PO Acyclovir 800mg TDS x 2/7
- PO Valacyclovir 500mg BD x 3/7
- PO Valacyclovir 1g OD x 5/7
How should the sexual partners of a genital herpes patient be managed?
- 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, encouraged to examine themselves for lesions and seek medical attention if lesions occur. May be offered type-specific serologic testing for HSV-2
