Infections of the genital Tracts Flashcards
What’s the difference between an STD and an STI
Sexually transmitted infection (STI) – Includes both symptomatic & asymptomatic cases – Sexual activity is the principle mode of transmission
Sexually transmitted disease (STD) – Symptomatic cases only
What groups are at risk of STIs?
• Young people • Certain ethnic groups • Low socio-economic status groups • Specific aspects of sexual behaviour – Age at first sexual intercourse – Number of partners – Sexual orientation – Unsafe sexual activity
Why have the incidence of STIs been increasing?
- Increased transmission – changing sexual and social behaviour – increasing density and mobility of populations
- Increased GUM (genitourinary medicine) attendance so more diagnosis
- Greater public, medical and national awareness (e.g. with campaigns)
- Improved diagnostic methods including screening programs
What issues do STIs cause?
- Both acute and chronic/relapsing infections
- Stigma – impact on diagnosis & tracing contacts
- Consequent pathology – PID and infertility – Reproductive tract cancers
- Disseminated infections
- Transmission to foetus/neonate
How are STIs managed and what must be considered post diagnosis?
- Treatment preferably single dose/short course
- Co-infections are common because all the risk factors for a STI is the same for many other so must screen & consider empiric treatment for other STIs
- Contact tracing – patient & public health management
- Sexual health education, advice on contraception, and detailed instruction on the practice and need for safer sex
Describe the type of human papillomavirus and what they cause
There are >100 HPV types of this DNA virus It causes cutaneous, mucosal, and anogenital warts. HPV 6 & 11 – Benign, painless, epithelial, or mucosal outgrowths, penis, vulva, vagina, urethra, cervix, perianal skin. High-risk types (oncogenic) – HPV16 & HPV18 – Associated with cervical (>70%) and anogenital
How is HPV diagnosed, treated and screened for?
- Diagnosis – clinical, biopsy + genome analysis,
- Treatment – None – spontaneous resolution (70% 1 yr, 90% 2yrs) – Topical podophyllin, cryotherapy, intralesional interferon, imiquimod, surgery
- Screening – Cervical Pap smear cytology –
What are the two HPV vaccines?
Two types – Cervarix (HPV 16 & 18 just oncotic ones) initially used in UK – Gardasil (HPV 6,11,16 & 18 both benign and oncotic ones) from 2011. 99% effective in preventing HPV 16 & 18 - related cervical abnormalities in those not already infected.
Describe what causes chlamydia, how it affects men, women and children differently and how we treat them differently?
Chylamydia trachomatis - obligate intra-cellular bacterium causing Non-specific genital chlamydial infections. Males – urethritis, epididymitis, prostatitis, proctitis (infection of anal area). Females – urethritis, cervicitis, salpingitis (fallopian tubes), perihepatitis – referred shoulder tip pain. Neonatal infection – conjunctivitis, pneumonia. Treatment: doxycycline or azithromycin and erythromycin in children.
How is chlamydia diagnosed?
- Endocervical and urethral swabs but more commonly use 1st void urine – NAAT
- Neonatal infection – conjunctival swab (NAAT) Treatment. Many cases asymptomatic esp. in women.
- Dual testing (with N. gonorrhoeae) available.
What causes Herpes?
Herpes Simplex Virus
How does Herpes present and why can it be recurrent?
Primary genital herpes – extensive painful genital ulceration, dysuria, inguinal lymphadenopathy and fever. Genital herpes is usually associated with HSV2 (HSV1 usually causes cold sores). Recurrent genital herpes – latent infection in dorsal root ganglia.
How is herpes diagnosed and treated?
Diagnosis – PCR of vesicle fluid and/or ulcer base. Treatment – aciclovir (1° & severe disease). Aciclovir prophylaxis for frequent recurrences. Barrier contraception reduces risk of transmission
What causes gonorrohea, how does it affect men and women differently and what happens in disseminated gonococcal infection?
Gram negative intracellular diplococcus that replicate inside white cells. Males – urethritis, epididymitis, prostatitis, proctitis and pharyngitis. Females – asymptomatic, endocervicitis, urethritis and PID which may lead to infertility. Disseminated gonococcal infection – Bacteraemia, skin & joint lesions
How is gonorrohea diagnosed and treated?
- Diagnosis – swab from urethra, cervix (throat, rectum) or urine (NAAT)
- Gram stain from pus or normally sterile site
- Treatment – ceftriaxone (IM), increasing resistance to many other agents
- All patients treated (& tested) for gonorrhoea are also tested (and treated) for chlamydia with azithromycin
What causes syphilis and why are we worried about it in women specifically?
Treponema pallidum (spirochaete) is the aetiological agent of syphilis and is most common in men and MSM. Congenital syphilis passed on from the mother is severe and life threatening.
Describe the stages of a syphilis (Treponema pallidum (spirochaete))infection?
- Indurated, painless ulcer (chancre)
- 6 to 8 weeks later – fever, rash, lymphadenopathy, mucosal lesions in mouth
- Latent – symptom-free years
- Neurosyphilis (GPI general paralysis of the insane – tabes dorsalis), cardiovascular syphilis, gummas (local destruction)
How is syphilis (Treponema pallidum (spirochaete)) diagnosed and treated?
Diagnosis – cannot be grown, instead Serology (blood serum examination)– Initial screening with EIA (enzyme immunoassay) antibody test
Treatment – penicillin & ‘test of cure’ follow up
What are the three main causes of inguinal lymphadenopathy, describe each?
– LGV (lymphogranuloma venereum)
• C. trachoma serotypes L1, L2 & L3
• Rapidly healing papule (small swelling and rash) then inguinal bubo (abscess)
• Recent clusters in europe in MSM
– Chancroid (Haemophilus ducreyi) – Painful genital ulcers
– Granuloma inguinale/Donovanosis (Klebsiella granulomatis). Genital nodules→ ulcers
What is Trichomonas vaginalis
Flagellated protozoan causing trichomonas vaginitis – Thin, frothy, offensive discharge – Irritation, dysuria, vaginal inflammation. Diagnosis – looking for it and molecular techniques, treated with metronidazole
What causes Vulvovaginal candidiasis, what are the risk factors, how is it diagnosed and how do you treat it?
Candida albicans. Risk factors – antibiotics, oral contraceptives, pregnancy, obesity, steroids, diabetes. Causes Profuse, white, itchy curd-like discharge. Diagnosis – high vaginal smear.
Treatment - topical azoles or nystatin, or oral fluconazole
What are Scabies and pubic lice
Scabies can affect the genitalia and spread sexually. Pubic lice (pediculosis pubis) – Distinct from the other human (body) lice ‘crabs’
What is bacterial vaginosis, how is it diagnosed and treated?
Disturbance of normal flora – Gardnerella, anaerobes, mycoplasmas. Causes scanty but offensive fishy discharge not creamy or itchy like candid. Clinical diagnosis – vaginal pH >5, KOH whiff test. Laboratory diagnosis – HVS Gram stained smear – ‘clue’ cells – epithelial cells studded with Gram variable coccobacilli – Reduced numbers of lactobacilli – Absence of pus cells. Treatment - metronidazole
