Show Notes

(1:49) Chlamydia

(3:31) Gonorrhea

(4:50) PID

(6:14) Syphilis

(8:08) Neurosyphilis

(9:13) Tertiary Syphilis

(10:06) Trichomoniasis

(11:13) Herpes

(12:49) HIV

(14:10) PEP

(15:13) Mycoplasma Genitalium

(18:00) Take Home Points

Chlamydia:

Prevalence:

- - Most common STI.
  - High percentage of asymptomatic cases (40% to 96%).

Presentation:

- - Urethritis, cervicitis, pelvic inflammatory disease (PID), prostatitis, proctitis, pharyngitis, arthritis.
  - Importance of considering extra-genital sites (oral and rectal infections).

Testing:

- - Gold Standard: Nucleic Acid Amplification Test (NAAT) via PCR.

Sampling Sites:

- - - Endocervical or urethral swabs preferred over urine samples due to higher sensitivity.
    - Triple-site testing (genital, rectal, pharyngeal) recommended for comprehensive detection.

Treatment Updates:

- - Previous Regimen: Azithromycin 1 g orally in a single dose.
  - Current First-Line Treatment: Doxycycline 100 mg orally twice daily for 7 days.

Alternatives:

- - Azithromycin remains an option for patients unlikely to adhere to a 7-day regimen or for pregnant patients.
- Note: PID treatment differs and will be discussed separately.

Gonorrhea:

Presentation:

- - Similar to chlamydia; can be asymptomatic.
  - Symptoms include urethritis, cervicitis, PID, prostatitis, proctitis, pharyngitis.

Testing:

- - Gold Standard: NAAT.

Sampling Sites:

- - - Endocervical swabs are more sensitive than urine samples.
    - Triple-site testing is crucial to avoid missing infections.

Treatment Updates:

- - Previous Regimen: Ceftriaxone 250 mg IM plus azithromycin 1 g orally.
  - Current Recommendation: Ceftriaxone 500 mg IM single dose.
    - Adjusted due to rising azithromycin resistance and updated pharmacokinetic data.

Co-Infection Considerations:

- High rates of chlamydia and gonorrhea co-infection (20% to 40%).
- CDC recommends empiric treatment for chlamydia when treating gonorrhea to prevent complications like PID and infertility.

Pelvic Inflammatory Disease (PID):

Etiology:

- - Not solely caused by chlamydia and gonorrhea; about 50% of cases involve other pathogens like bacterial vaginosis (BV) organisms and anaerobes.

Treatment Changes:

Expanded Coverage Regimen:

- - Ceftriaxone 500 mg IM once.
  - Doxycycline 100 mg orally twice daily for 14 days.
  - Metronidazole 500 mg orally twice daily for 14 days.
- Inclusion of metronidazole addresses anaerobic bacteria contributing to PID.

Syphilis:

Stages and Presentation:

Primary Syphilis:

- - Painless chancre on genitals.
  - Treatment: Penicillin G 2.4 million units IM single dose.

Secondary Syphilis:

- - Rash (often diffuse), mucocutaneous lesions, nonspecific joint pain.
  - Treatment: Same as primary syphilis.

Latent Syphilis:

- - Asymptomatic phase; divided into early (<1 year) and late (>1 year).

Treatment for Late Latent:

- Penicillin G 2.4 million units IM once weekly for 3 weeks.
- Recommended when the timing of infection is unclear.

Neurosyphilis:

Can occur at any stage.
Symptoms include visual changes, severe headaches, neurological deficits.

Diagnosis: Requires lumbar puncture (LP) for confirmation.
Treatment: Admission for intravenous penicillin G.

Tertiary Syphilis:

Rare, advanced stage with severe manifestations (e.g., gummas, cardiovascular complications, neurological signs).
Treatment: Extended penicillin therapy similar to late latent syphilis.

Trichomoniasis:

Presentation:

- - Often asymptomatic.
  - In women: Vaginal discharge.
  - In men: Urethritis.

Testing:

- - Shift from wet mount microscopy to NAAT for improved detection.
  - Swab samples preferred over urine for higher sensitivity.

Treatment Updates:

- - Previous Regimen: Metronidazole 2 g orally in a single dose.

Current Recommendations:

- - Women: Metronidazole 500 mg orally twice daily for 7 days.
  - Men: Single 2 g dose remains acceptable.

Herpes Simplex Virus (HSV):

Types and Transmission:

- - HSV-1 and HSV-2: Both can cause oral and genital infections.
  - Increasing crossover between oral and genital sites.

Testing:

- - Serum IgG testing not useful for acute diagnosis due to widespread prior exposure.
  - Preferred Method: PCR testing from lesion swabs.
- Clinical Tip: If the lesion is characteristic, clinicians may start treatment without waiting for test results.

Treatment:

- - Preferred Medication: Valacyclovir (Valtrex) for ease of dosing.

Dosage:

- - Initial episode: 1 g orally twice daily for 7 to 10 days.
  - Recurrence: 1 g daily for 5 days.
- Alternative: Acyclovir for cost considerations.

Human Immunodeficiency Virus (HIV):

Testing Limitations:

Window Periods:

- - - Fourth-generation tests have a window period of 2 to 4 weeks.
    - Negative results during this period may not rule out recent infection.

Acute HIV Infection:

- - Presents with flu-like symptoms: malaise, joint pains, fatigue.

Diagnosis Challenges:

- - Standard HIV tests may be negative during the window period.

Options:

- - - Empiric treatment with follow-up testing.
    - Order an HIV viral load test (more sensitive but expensive and delayed results).

Post-Exposure Prophylaxis (PEP):

- - Timing: Initiate ideally within 72 hours of potential exposure.
  - Duration: 28-day regimen.

Pre-Treatment Testing:

- Baseline HIV test to rule out existing infection.
- Renal and hepatic function tests to monitor for medication side effects.
Follow-Up: Reassess renal/hepatic function in 2 weeks.

Mycoplasma genitalium:

Recognition:

- - Newly recognized STI by the CDC in 2021.
  - Causes cervicitis and urethritis.
  - Possible associations with PID and proctitis, but not definitively established.

Testing:

When to Test:

- - - Only in patients with persistent symptoms after standard STI testing and treatment.
    - Not recommended for initial screening.
  - Method: NAAT.

Treatment:

- - Step 1: Doxycycline 100 mg orally twice daily for 7 days.
  - Step 2: Moxifloxacin 400 mg orally once daily for 7 days.
  - Addresses antibiotic resistance concerns and ensures comprehensive treatment.

General Management and Patient Counseling:

Partner Notification:

- - - Encourage patients to inform sexual partners for testing and treatment.

Medication Adherence:

- - - Emphasize the importance of completing the full course of prescribed medications.

Prevention Measures:

- - - Discuss the use of barrier protection (e.g., condoms) to prevent transmission and reinfection.

Follow-Up Care:

- - Advise patients to return if symptoms persist, indicating possible infections like Mycoplasma genitalium.

Key Take-Home Points:

Chlamydia Treatment Update:

- - Doxycycline 100 mg orally twice daily for 7 days is now first-line treatment for cervical infections.
  - For epididymitis, extend doxycycline to 10 days.

Gonorrhea Treatment Update:

- - Treat with a single 500 mg IM dose of ceftriaxone.

PID Management Update:

- - Expanded antimicrobial coverage includes:
    - Ceftriaxone 500 mg IM once.
    - Doxycycline 100 mg orally twice daily for 14 days.
    - Metronidazole 500 mg orally twice daily for 14 days.

Mycoplasma genitalium Recognition:

- - Test in patients with persistent symptoms after standard treatment.
  - Treat with doxycycline followed by moxifloxacin.

HIV Testing and PEP:

- Be aware of HIV test window periods; negative results may not rule out recent infection.
- Consider HIV viral load testing if acute infection is suspected.
- Initiate PEP within 72 hours for a 28-day course, ensuring clear discharge planning and patient support.

Show Notes

Table of Contents

Episode 202: Sexually Transmitted Infections 2.0

Core EM - Emergency Medicine Podcast