STD Testing for Men: Methods, Indications, and Accuracy

Routine screening and symptom-driven testing use different modalities. NAATs are the gold standard for most bacterial STIs.

Test Modalities

Specimen	Tests	Infections Detected
Urine (first-catch)	NAAT	Chlamydia, Gonorrhea, Trichomonas, M. genitalium
Urethral swab	NAAT, Culture	Gonorrhea (culture for antimicrobial susceptibility), Chlamydia
Blood (serum)	Serology	HIV Ag/Ab, Syphilis (RPR/VDRL + treponemal), HSV-1/2 IgG, HBV (HBsAg, anti-HBc), HCV Ab
Rectal/Pharyngeal swab	NAAT	Gonorrhea, Chlamydia (extragenital screening for MSM)
Lesion swab	NAAT, PCR, Culture, Tzanck	HSV, Syphilis (dark field), Mpox, LGV

Screening Recommendations (CDC/USPSTF)

• All sexually active MSM: Annual HIV, syphilis, chlamydia, gonorrhea (urethral, rectal, pharyngeal).
• Heterosexual men: Risk-based; routine chlamydia screening not recommended unless high prevalence setting.
• HIV PrEP users: Quarterly HIV, syphilis, GC/CT (3-site).

Rapid Point-of-Care

HIV Ag/Ab (4th gen), syphilis RPR, HCV Ab – results in 20 min; confirmatory testing required for positives.

Key Counseling Points

• Window periods: HIV 18–45 days (Ag/Ab), syphilis 3–6 weeks, GC/CT 1–2 weeks.
• NAAT sensitivity >95%, specificity >99%.
• Expedited partner therapy (EPT) for GC/CT where legal.