Viral STIs + skin lesions Flashcards
(24 cards)
How does herpes present (primary and recurrent)?
PRIMARY (most severe)
-Flu-like illness
-Vulvitis
-Painful vesicles on the vulva
-Urinary retention due to pain on passing urine
RECURRENT
-Often asymptomatic
-Triggered by stress, sex, menstruation
How is herpes diagnosed?
-Viral PCR of vesicle fluid ie skin swabs
How is herpes managed?
-Aciclovir 400mg TDS - reduces severity and duration of flare
-Saline baths, emla cream, lignocaine gel
What implications does herpes have for pregnancy?
-Risk of transmission to baby is low unless 1st infection in last stages of pregnancy (consider C section)
-Consider acyclovir if recurrent infections throughout pregnancy
Which HPV types cause genital warts?
-Types 6 + 11
How do genital warts present?
-Most infections of HPV are asymptomatic
-Can cause local skin irritation / catch on clothing
-Small, fleshy painless lump, spread in lines of trauma
How are genital warts diagnosed?
-Mostly clinical
-May be found on cervical cytology from smear
-May require biopsy to exclude neoplasia
How are genital warts managed?
-Podophyllotoxin topical treatment BD 3 days on 4 days off for 6 weeks
-Imiquimod 2nd line
-Cryotherapy, excision
Where do molluscum contagiosum lesions appear?
-Genitals, pubic region
-Lower abdomen, upper thighs
-Buttocks
-Clear on their own
How does the primary phase of syphilis infection present?
-Painless genital ulcer (= CHANCRE) - red, raised, well demarcated with indurated edge
-Inguinal lymphadenopathy
-Usually 10-90 days post infection
How does the secondary phase of syphilis infection present?
-Develops in 25% of those who leave primary untreated
-Painless warty genital lesions (= CONDYLOMATA LATA)
-Hepatitis
-Splenomegaly
-Glomerulonephritis
-Neuro conditions eg CN palsies, meningitis, optic neuropathy, psychiatric symptoms
-Rash on palms and soles
-Occurs within 2 years of infection (but usually 4-10 weeks)
How does the tertiary phase of syphilis present?
-Neurosyphilis
-Cardiovascular effects
-Gummatous of skin and bones
How is syphilis diagnosed?
-Bloods - VDRL carbon antigen test, RPR test for screening
-Swab from primary lesion for dark field microscopy + PCR
How do you manage syphilis?
Abx for symptoms
-Benzylpenicillin IM for 3 weeks (single dose if primary, secondary or early tertiary)
Doxy
-Erythromycin
What implications does syphilis have for pregnancy?
Increased risk of:
-Preterm delivery
-Stillbirth
-Congenital syphilis (saddle nose, deafness, keratitis)
-Wrinkling around mouth
What receptor does HIV bind to in human cells and what does this result in?
-CD4 on helper T cells, monocytes, macrophages and neural cells
What is viral load used to predict?
-Impact of virus on immunity ie progression to AIDS
-CD4 count declines as viral load increases
What occurs if HIV is left untreated?
-All cell-mediated immunity is progressively damaged
-Leaving patient more susceptible to infection and malignancies
What antigens are tested for when testing for HIV and when should this be done?
-p-24 antigen
–Detected after 3-4 weeks of infection then reduces to v low levels after 8 weeks
-HIV RNA
–Sensitive 1 week before seroconversion symptoms
-HIV antibody
–Takes 4-8 weeks to develop
-4th generation tests recommended (tests for both), 3rd gen just tests for antibody and done in 12-week window
What are the stages of HIV infection?
- HIV binding + integration
–Takes 3-5 days after exposure - Seroconversion –> primary infection
–Causes flu-like symptoms in 70% of patients
–Transient, 2-12 weeks post exposure - Period of asymptomatic infection
–Average 5-10 years
–Some constitutional symptoms eg night sweats, diarrhoea - AIDS
–Typically around 8 years after infection (if no treatment)
–Death within 2 years if no treatment
What is considered a low CD4 count?
<200
-<350 at diagnosis indicates poor prognosis
What is the risk of vertical transmission for HIV?
-If viral load <50 - vaginal delivery is possible
-Prolonged labour is a risk factor for VT
-C-section recommended if >400
-Neonatal PEP for 4 weeks in viral load >50
-Able to breastfeed if counselled and viral load is low
When can PEP be used?
-Consider for anyone having UPSI / condom failure with a high-risk contact in last 72h
-Taken for 28 days
When should PrEP be used?
-Before, during and after sex
-For HIV negative people
