STIs ext

PART 1: INTRODUCTION AND EPIDEMIOLOGY

Section 1: Outline of Talk (Page 1)

The lecture covers:

• What STIs are there?

• Epidemiology

• Clinical cases

• Common STIs and their management

• HIV:

  • Epidemiology

  • Testing

  • PrEP (Pre-Exposure Prophylaxis)

• Questions

Also covers: Thrush, Bacterial vaginosis

Section 2: Epidemiology of STIs in England (Pages 3-10)

2.1. Number of New STI Diagnoses: England, 2015 to 2024 (Page 3):

• Graph showing trends in STI diagnoses over the decade.

• Key trend: Overall increase in STI diagnoses, with fluctuations during COVID-19 pandemic years.

2.2. Rates of New STI Diagnoses by Gender and Age Group: England, 2024 (Page 4):

• Highest rates: Among young adults (15-24 years) .

• Women have higher rates than men in the younger age groups, but this balances in older age.

2.3. Chlamydia Diagnoses by Gender: England, 2015 to 2024 (Page 5):

• Chlamydia is the most diagnosed STI.

• Higher rates in women (likely due to higher screening rates).

2.4. Gonorrhoea Diagnoses by Gender: England, 2015 to 2024 (Page 6):

• Significant increase in gonorrhoea diagnoses over the decade.

• Particularly marked increase in men (especially MSM).

2.5. Syphilis Diagnoses by Gender: England, 2015 to 2024 (Page 7):

• Dramatic increase in syphilis diagnoses, especially in men.

2.6. Genital Herpes (First Episode) Diagnoses by Gender: England, 2015 to 2024 (Page 8):

• Relatively stable rates, with some fluctuation.

• Slightly higher in women.

2.7. Genital Warts (First Episode) Diagnoses by Gender: England, 2015 to 2024 (Page 9):

• Declining rates – attributable to the HPV vaccination programme.

2.8. Rates of STI Diagnoses by Ethnic Group Among Women: England, 2024 (Page 10):

• Significant disparities exist, with higher rates in some ethnic minority groups (e.g., Black Caribbean, Black African populations).

2.9. Proportion of STI Diagnoses Based on Sexual Orientation: England, 2024 (Page 10):

• Disaggregated by:

  • Heterosexual women

  • Heterosexual men

  • Gay, bisexual, and other men who have sex with men (MSM)

• MSM account for a disproportionate burden of certain STIs (e.g., gonorrhoea, syphilis, HIV).

2.10. Rates per 100,000 Population of New STI Diagnoses by Local Authority of Residence: England 2024 (Page 11):

• Map showing geographical variation in STI rates.

• Higher rates in urban areas, particularly London and other major cities.

2.11. Where Are People Testing? (Page 12):

• Testing occurs in various settings:

  • Sexual health clinics (GUM clinics)

  • Community pharmacies

  • GP surgeries

  • Online self-sampling services

  • Antenatal clinics

  • Increasingly, opt-out testing in Emergency Departments (for HIV)

PART 2: CLINICAL CASES – BACTERIAL STIs

Section 3: Case 1 – Urethral Discharge (Pages 13-17)

3.1. Case Presentation (Page 13):

• 37-year-old cis-gender man

• Symptoms: Urethral discharge and dysuria (pain on urination)

• History: Casual female partner 5 days ago; no condom use

• Diagnosis: Non-specific urethritis (NSU)

3.2. Initial Treatment (Page 13):

• Doxycycline 100 mg orally twice daily for 7 days

• Advise to abstain from sex until treatment completed and partner treated

• Partner notification (contact tracing)

• Offer full sexual health screen (including HIV, syphilis)

Section 4: Chlamydia trachomatis (Page 14)

• Epidemiology: The most diagnosed STI in the UK.

• Symptoms: Variable. Many patients can be asymptomatic.

• Complications:

  • Pelvic Inflammatory Disease (PID) – can lead to infertility, ectopic pregnancy, chronic pelvic pain.

  • Epididymo-orchitis – inflammation of epididymis and testis in men.

• Treatment: Doxycycline 100 mg orally twice daily for 7 days (first-line). Alternative: Azithromycin 1g single dose (if doxycycline contraindicated).

Section 5: Gonorrhoea (Page 15)

• Epidemiology: The second most common STI.

• Risk Groups: More common amongst MSM (Men who have Sex with Men) .

• Symptoms: More likely to have symptoms vs. chlamydia, but can be asymptomatic.

• Complications: Similar to chlamydia – PID, epididymo-orchitis, reactive arthritis.

• Antimicrobial Resistance: Major concern. Resistance to multiple antibiotic classes has emerged.

• Treatment: Ceftriaxone 1 g intramuscular (IM) once only (current first-line).

Section 6: Mycoplasma genitalium (Page 16)

• Type: Bacterial sexual infection.

• Symptoms: Most people are asymptomatic.

• Antimicrobial Resistance: Significant concern. Resistance to macrolides (azithromycin) and fluoroquinolones is common.

• Treatment (Regimen 1): Doxycycline 100 mg orally twice daily for 7 days, then Azithromycin 1g oral STAT and 500 mg oral once daily for 2 days.

• Treatment (Regimen 2): Doxycycline 100 mg orally twice daily for 7 days, then Moxifloxacin 400 mg oral once daily for 7 days (used if macrolide resistance suspected/confirmed).

Section 7: Symptoms of Bacterial STIs by Site (Page 17)

PART 3: CLINICAL CASES – VAGINAL DISCHARGE

Section 8: Case 2 – Vaginal Discharge (Pages 18-19)

8.1. Case Presentation (Page 18):

• 24-year-old cis-gender woman

• Symptoms: New watery vaginal discharge

  • Grey/white colour

  • No smell

  • Itchiness inside vagina

• History: New male partner – he is asymptomatic; occasional condom use

• Presentation: Abnormal vaginal discharge

8.2. Differential Diagnosis of Abnormal Vaginal Discharge (Page 19):

Section 9: Trichomonas vaginalis (TV) (Page 20)

• Type: Protozoan parasite (not a bacterium).

• Symptoms: Frothy, yellow-green vaginal discharge with offensive smell; vulvovaginal irritation; dysuria.

• Treatment: Metronidazole 400 mg orally twice daily for 7 days.

• Advice: Abstain from sex until treatment completed and partner treated.

• Partner notification: Sexual partners need treatment.

• Full sexual health screen: Offer testing for other STIs.

Section 10: Non-STI Causes of Vaginal Discharge

10.1. Thrush (Vulvovaginal Candidiasis):

• Symptoms: Thick, white, "cottage cheese-like" discharge; intense itching; vulval erythema.

• Treatment: Topical or oral antifungals (e.g., clotrimazole, fluconazole).

10.2. Bacterial Vaginosis (BV):

• Symptoms: Thin, white/grey discharge with fishy odour (especially after sex). Not usually itchy.

• Treatment: Metronidazole (oral or topical).

PART 4: CLINICAL CASES – GENITAL ULCERS

Section 11: Case 3 – Genital Ulcer (Pages 21-22)

11.1. Case Presentation (Page 21):

• 35-year-old cis-gender gay man

• Symptoms: Genital ulcer, appeared a week ago

  • Painless

• History: Well, no medical problems, no medication

  • Multiple casual male partners

  • Condomless sex

  • History of "chemsex" drug use in the past

11.2. Examination Findings (Page 22):

• Small genital ulcer on the shaft

  • Clear edge, no blistering

  • Painless

• Enlarged inguinal lymph nodes (lymphadenopathy)

• STI screen a week later: Positive for syphilis

11.3. Diagnosis: Syphilitic chancre (primary syphilis)

Section 12: Differential Diagnosis of Genital Ulcers (Page 23)

Section 13: Herpes Simplex Virus (HSV) (Page 24)

• Type: Very common virus. Same virus responsible for cold sores.

  • HSV-1: Typically oral (cold sores), but can cause genital herpes.

  • HSV-2: Typically genital herpes.

• Prevalence: Around 80% of the adult population have HSV (mostly HSV-1).

• Symptoms: Painful ulcers in genital area; shallow, well-defined ulcers.

• Treatment: Aciclovir 400 mg TDS orally for 5 days.

• Supportive care: Analgesia, saline bathing, topical anaesthetics (lidocaine).

• Education: Recurrences are common; discuss transmission, suppression therapy if frequent.

Section 14: Syphilis – Treponema pallidum (Pages 25-27)

14.1. The Organism (Page 25):

• Spiralled spirochete (bacteria).

• Transmission: Vertical (mother-to-child) and sexual.

• Host: Humans are the only reservoir of infection.

14.2. Clinical Features (Page 25):

• Multi-stage disease – challenging to identify what stage.

• Multi-system disease.

Image Description (Page 25): Images of primary syphilis chancre and secondary syphilis rash on palms and soles.

14.3. Syphilis Staging and Treatment (Page 26):

• Primary, secondary, or early latent syphilis:

  • Treatment: Benzathine penicillin 2.4 million units IM injection (single dose) .

  • Alternatives: Doxycycline, gentamicin (if penicillin allergic).

  • Advice: Abstain from sex; partner notification; follow-up for compliance and treatment success (serological testing).

• Jarisch-Herxheimer reaction:

  • A paradoxical worsening of symptoms (fever, chills, myalgia, headache) occurring within 24 hours of treatment.

  • Common in early infection.

  • Due to rapid killing of spirochetes and release of endotoxins.

  • Manage with supportive care (antipyretics); not an allergic reaction.

Section 15: Chemsex (Page 27)

• Definition: The use of drugs before or during planned sexual activity to sustain, enhance, disinhibit, or facilitate the experience.

• Context: Often associated with sex on premises (e.g., saunas, sex parties).

• Consequences:

  • Increased risk of HIV and STIs (due to condomless sex, multiple partners).

  • Negative harms in personal life, work, relationships, and mental health.

• Clinical Implication: These are complex patients to manage – require holistic, non-judgemental care, often with input from drug and alcohol services, mental health, and sexual health.

PART 5: PREVENTION

Section 16: Window Periods for STI Testing (Page 28)

• Definition: The time between exposure to the infection and the point when a test can reliably detect it.

• Clinical Implication: Patients may need repeat testing after the window period if initial test is negative but exposure was recent.

Section 17: Prevention Strategies (Pages 29-30)

17.1. General Prevention (Page 29):

• Education – about STIs, transmission, and prevention.

• Recognising signs and symptoms – to encourage early testing.

• Regular testing – especially for those at higher risk.

• Condoms! – still the most effective protection against most STIs.

17.2. Specific Interventions for Prevention (Page 30):

PART 6: HIV

Section 18: HIV Epidemiology in the UK (Pages 31-33)

18.1. HIV Diagnoses: UK, 2004 to 2024 (Page 31):

• Graph showing trends.

• Peak in diagnoses in the mid-2000s, followed by a decline, particularly in recent years (due to effective prevention, PrEP, and treatment as prevention).

18.2. New HIV Diagnoses in Key Adult Populations: England, 2019 to 2024 (Page 32):

• Data disaggregated by:

  • Gay, bisexual, and other MSM

  • Heterosexual men

  • Heterosexual women

  • People who inject drugs (PWID)

• MSM and heterosexual men and women account for the majority of new diagnoses.

18.3. HIV Prevalence per 1000: England 2023 (Page 33):

• Map showing geographical variation in HIV prevalence.

• Highest prevalence in London (>5 per 1000), followed by other urban areas (Brighton, Manchester).

Section 19: U = U (Undetectable = Untransmittable) (Page 34)

• Key Message: A person living with HIV who is on effective antiretroviral therapy (ART) and has an undetectable viral load cannot transmit HIV to their sexual partners.

• Scientific Evidence: Proven by multiple large studies (PARTNER, HPTN 052, Opposites Attract).

• Impact: Reduces stigma, encourages testing and treatment.

Section 20: Opt-Out Testing for HIV in Emergency Departments (Page 35)

• Introduced at Kingston Hospital (KHFT) in November 2021.

• Opt-out testing for all patients who have blood tests in the Emergency Department (ED).

• In line with all other trusts in South London.

• NICE recommends in regions of prevalence >2 per 1000:

  "offer and recommend HIV testing on admission to hospital, including emergency departments, to everyone who has not previously been diagnosed with HIV and who is undergoing blood tests for another reason."

Section 21: Why Test for HIV? (Page 36)

• Bringing the diagnosis forward is always beneficial vs. leaving it late.

• Benefits of knowing if you are HIV positive:

  • Prolong life expectancy (near-normal with modern ART).

  • Reduce risk of hospital admission (prevent opportunistic infections).

  • Prevent onward transmission: "U equals U" (once on effective treatment).

  • Antiretroviral therapy is highly effective and relatively low cost.

Section 22: Pre-Exposure Prophylaxis (PrEP) (Pages 37-38)

22.1. What is PrEP? (Page 37):

• Medication taken BEFORE exposure to HIV to prevent infection.

• It is effective!

• Adherence is key – effectiveness depends on taking it as prescribed.

• Offered to those at risk of HIV:

  • MSM engaging in condomless sex

  • Sex workers

  • Other individuals at risk (e.g., heterosexual individuals with partners from high-prevalence areas, people who inject drugs)

• Medication: Tenofovir Disoproxil + Emtricitabine (combination tablet).

• Availability: Available in sexual health clinics and privately online.

22.2. PrEP Dosing Regimens (Page 38):

SUMMARY TABLE: COMMON STIs AND THEIR MANAGEMENT