What is the diagnosis and treatment for a patient with a suspected STI (Sexually Transmitted Infection)-related throat infection confirmed by throat swab?

Diagnosis and Treatment of STI-Related Throat Infections

For suspected STI-related throat infections confirmed by throat swab, the recommended approach is to treat for both gonorrhea and chlamydia with ceftriaxone 250 mg IM in a single dose plus doxycycline 100 mg orally twice daily for 7 days.

Diagnosis of Pharyngeal STIs

• Culture is the most widely available option for diagnosis of N. gonorrhoeae in pharyngeal sites, as non-culture tests (NAATs) are not FDA-cleared for use in the pharynx 1
• Some NAATs have potential to cross-react with non-gonococcal Neisseria species commonly found in the throat 1
• Gram stain of pharyngeal specimens is not sufficient to detect infection and is not recommended 1
• Some non-commercial laboratories have initiated NAAT testing of pharyngeal swab specimens after establishing performance to meet CLIA requirements 1
• Pharyngeal infections with N. gonorrhoeae or C. trachomatis can cause pharyngitis and tonsillitis with sore throat, but are completely asymptomatic in most cases 2

Treatment Recommendations

Primary Treatment Regimen

• Ceftriaxone 250 mg IM in a single dose, PLUS
• Doxycycline 100 mg orally twice a day for 10 days 1

Rationale for Dual Therapy

• Patients infected with N. gonorrhoeae are frequently coinfected with C. trachomatis 1
• Dual therapy helps prevent development of antimicrobial-resistant N. gonorrhoeae 1
• If chlamydial test results are not available or if a non-NAAT was negative for chlamydia, patients should be treated for both gonorrhea and chlamydia 1

Special Considerations

• For patients who cannot tolerate cephalosporins or quinolones, spectinomycin is an alternative 1
• Because spectinomycin is only 52% effective against pharyngeal infections, patients with pharyngeal infection should have a pharyngeal culture 3-5 days after treatment to verify eradication 1
• Pregnant women should not be treated with quinolones or tetracyclines; they should receive a recommended cephalosporin 1
• For pregnant women who cannot tolerate cephalosporins, spectinomycin 2g IM as a single dose is recommended 1

Follow-up and Test of Cure

• A test of cure for pharyngeal gonorrhea should not be performed less than 7 days after treatment 3
• Persistence after treatment was found in 4.6% of pharyngeal gonorrhea cases in one study 3
• Persistence was less likely with combination antibiotic therapy and with longer time from treatment to test of cure 3
• When test of cure was performed 15-28 days after treatment, persistence was found in only 1% of cases 3

Partner Management

• Sex partners of patients with N. gonorrhoeae infection whose last sexual contact with the patient was within 60 days before onset of symptoms or diagnosis should be evaluated and treated 1
• If a patient's last sexual intercourse was >60 days before onset of symptoms or diagnosis, the patient's most recent sex partner should be treated 1
• Patients should be instructed to avoid sexual intercourse until therapy is completed and until they and their sex partners no longer have symptoms 1

Additional Testing Recommendations

• All patients tested for gonorrhea should be tested for other STDs, including chlamydia, syphilis, and HIV 1
• For persistent gonococcal infection after treatment, clinicians should perform both culture and antimicrobial susceptibility testing 1

Common Pitfalls and Caveats

• Asymptomatic pharyngeal infections are an important but frequently overlooked reservoir for new infections 2
• Quinolone-resistant N. gonorrhoeae (QRNG) is increasingly common, making treatment with ciprofloxacin inadvisable in many areas 1
• When the tonsils and other difficult-to-reach tissues are infected, higher doses and antibiotics with good tissue penetration are recommended 2
• Self-collected throat swabs may have slightly higher rates of equivocal or invalid results compared to clinician-collected samples, but overall positivity rates are similar 4