STIs Flashcards
What is the most common bacterial STI?
Chlamydia Trachomatis
Which serovars are responsible for anogenital CT infection?
D-K
Which cell type does CT infect?
Columnar epithelium at mucosal sites
What is the typical male presentation of chlamydia?
Milky urethral discharge
Dysuria
Abdominal pain
Signs of urethritis or proctitis
What is the typical female presentation of chlamydia?
Irregular bleeding
Abdominal pain
Signs of cervicitis or proctitis
NB on discharge - poor predictive power on its own, but commonly reported.
How is chlamydia diagnosed?
NAAT 14 days following episode of risk
Male - first pass urine (hold for one hour)
Female - HVS or VVS
What is the first and second line management for uncomplicated CT infection?
- Doxycycline 100mg BD for 7 days
2. Azithromycin 1g single dose followed by 2 days of 1 x 500 mg doses
What are the complications of chlamydia?
Pelvic Inflammatory Disease- which can lead to ectopic pregnancy or tubal factor infertility Fitz-Hugh-Curtis Conjunctivitis Reactive Arthritis Reiter's Syndrome
“Can’t pee, can’t see, can’t climb a tree”
What is the treatment for complicated chlamydia infection?
Ceftriaxone 1g IM (GC cover), Doxycycline 100mg BD for 14 days (CT cover), and metronidazole 400mg BD x 14 days (anaerobe cover)
What organism causes Lymphogranuloma Venereum?
Chlamydia Trachomatis serovars L1-3
What are the symptoms of LGV?
Rectal pain, discharge and bleeding
Who is most at risk for LGV?
MSM
What are the gram stain characteristics of Chlamydia Trachomatis?
Does not gram stain as no peptidoglycan in the cell wal
What is the causative organism of gonorrhoea?
Neisseria Gonorrhoeae
What are the gram stain characteristics of Neisseria gonorrhoeae?
Gram-negative diplococcus (look like 2 kidney beans facing each other) which are easily phagocytosed therefore seen intracellularly
What is the typical presentation of a GC infection?
Male - purulent urethral discharge
Female - endocervical discharge 50%, irregular bleeding and external dysuria
NB pharyngeal and rectal cases are typically asymptomatic
How is GC infection diagnosed?
NAAT test
Microscopy used if symptomatic
Culture can be done if microscopy is +ve
What is the first and second-line management for GC infection?
- Ceftriaxone 1g IM
- Cefixime 400mg oral plus Azithromycin 2g
Test of cure for all patients
What are the possible complications of gonorrhea?
Lower tract - bartholinitis, tysonitis, periurethral abscess, rectal abscess, epidiymitis, urethral stricture
Upper tract - endometritis, PID, hydrosalpinx, infertility, ectopic pregnancy, postatitis
What is the DDx for genital ulceration?
Viral - HSV, VZV, EBV, HIV, syphilis Crohn's Fixed drug eruption Tropical STI Self harm Stevens Johnsons Lichen sclerosis Candida Behcet's
What is the diagnostic test for genital herpes?
Viral swab for HSV
How does genital herpes present at each different stage?
Primary - blistering ulcerations, flu-like prodrome, pain, external dysuria, vaginal or urethral discharge, local lymphadenopathy
Recurrent - unilateral, small blisters/ulcers, minimal systemic symptoms, pain is mild (can be described as tingling or itch)
Viral shedding occurs more frequently in HSV-1 or HSV-2?
HSV-2
When is viral shedding most likely to occur?
In the first year of infection
In people with frequent recurrences
What is the management for genital herpes?
Analgesia
Lidocaine 5% ointment
Antivirals within 5 days
What must be done if a pregnant woman presents with genital herpes?
Ix with HSV type-specific serology and NAAT to identify if primary or recurrent - if HSV type-specific if negative but NAAT is positive, then it is most likely primary and therefore there is high risk of neonatal herpes
HSV is an enveloped virus containing _______ stranded _______.
HSV is an enveloped virus containing double stranded DNA.
Where in the body does HSV reside?
sacral root ganglion
What organism causes Syphilis?
Treponema Pallidum (subspecifc pallidum)
What is the mode of transmission of syphilis?
Sexual contact or trans-placental
What are the different stages of syphilis infection?
Primary - <6weeks
Secondary - 6 weeks - 6 months
Early latent - < 2 years since exposure or last negative serology, asymptomatic
Late latent - > 2 years from known exposure of last negative serology, asymptomatic
Tertiary - 20-40 years later
What is the typical presentation of primary syphilis?
Painless chancre (may have pain) usually genital, sometimes with non-tender local lymphadenopathy
What is the typical presentation of secondary syphilis?
Macular, follicular, or papular rash which includes the palms and soles.
May also present with lesions on mucous membranes, generalised lymphadenopathy, fever, sore throat, malaise, anterior uveitis, cranial nerve lesions, condylomata lata
What are the complications associated with tertiary syphilis?
CVD e.g. aortic regurgitation
Stroke
How is syphilis diagnosed?
Gold top serological testing - ELISA/EIA
If this is positive then also follow up with TPPA and non-treponemal test (RPR).
What is the treatment for early syphilis infection?
2.4 MU Benzathine penicillin IM (stat)
What is the treatment for late syphilis infection?
2.4 MU Benzathine penicillin IM weekly for 3/52
What follow up testing should be done in syphilis?
Follow up RPR should be repeated until titer decreased fourfold (should be 3-6 months)
Syphilis EIA was reactive, RPR was reactive, but TPPA was non-reactive - what does this suggest?
Very early infection
Syphilis EIA is reactive, RPR is non-reactive, TPPA is reactive - what does this suggest?
Previous syphilis infection i.e. either treated, or late latent. Must confirm that patient has been treated. EIA and TPPA remain positive for life following infection.
What is the DDx for genital lumps?
Genital warts (HPV) Skin tags Molluscum contagiosum Spots of Fordyce Pearly penile papules
Which genotypes of anogenital HPV are considered low risk?
6, 11, 42, 43, 44
Which genotypes of HPV are considered high risk? Why are they high risk?
16 (most oncogenic), 18, 31, 33, 35, 45, 52 and 58
High risk as cause cellular dysplasia (oncogenic)
Which genotypes of HPV are covered by the vaccination?
6, 11, 16 and 18
New vaccine also 31, 33, 45, 52 and 58
Which genotypes are most commonly associated with anogenital warts?
6 and 11
What are the treatment options in anogenital warts?
Podophyllotoxin (Condyline)
Imiquimod (Aldara)
Cryotherapy
Electrocautery
What is the treatment for pubic lice?
Malathion lotion
