Infections, sexually transmitted diseases and preventive care
Introduction
The exam tests the differential diagnosis of vaginal discharge, pelvic inflammatory disease, the classic sexually transmitted infections and prevention - vaccination, screening and partner notification.
Vaginal discharge
- Bacterial vaginosis: clue cells, pH above 4.5, positive whiff test, thin grey discharge; three of four Amsel criteria or a Nugent score of 7–10. Treat with metronidazole 400–500 mg twice daily for 5–7 days.
- Vulvovaginal candidiasis: thick white discharge, itching, pseudohyphae; fluconazole 150 mg as a single dose, or a topical imidazole in pregnancy.
- Trichomoniasis: motile flagellates, frothy yellow discharge, strawberry cervix; metronidazole 2 g single dose and treat the partner.
Pelvic inflammatory disease
- Minimum criteria: lower abdominal pain plus cervical motion or adnexal tenderness, supported by fever, abnormal discharge, raised CRP or NAAT for chlamydia and gonorrhoea.
- Outpatient regimen: ceftriaxone 500 mg IM plus doxycycline 100 mg twice daily and metronidazole for 14 days. Remove an IUD only if there is no improvement at 48–72 hours.
- Complications: tubo-ovarian abscess, adhesions, ectopic pregnancy, infertility.
Sexually transmitted infections
- Chlamydia and gonorrhoea are diagnosed by NAAT; syphilis by combined treponemal and non-treponemal serology, treated with benzathine penicillin 2.4 million IU IM.
- Genital warts arise from HPV 6 and 11; HSV causes painful recurrent vesicles treated with aciclovir.
- Partner notification is both a clinical and legal duty; HIV and syphilis are notifiable in Czechia.
Prevention
- HPV vaccination before sexual debut, cervical cytology screening from 15 years, condoms that reduce but do not eliminate transmission.
- Hepatitis B vaccination and HIV pre-exposure prophylaxis for at-risk individuals.
Worked example
A 24-year-old has 5 days of lower abdominal pain, fever 38.2 °C and purulent discharge, with cervical motion tenderness and a tender right adnexa. NAAT is pending. Start ceftriaxone IM plus doxycycline and metronidazole immediately - treatment is empirical and must not wait for results - and arrange ultrasound to exclude a tubo-ovarian abscess plus review at 72 hours.
Traps
- Treating bacterial vaginosis with fluconazole.
- Missing PID because pain is mild and the white cell count is normal.
- Treating trichomonas without treating the partner.
- Assuming a negative NAAT taken immediately after exposure excludes infection.