What is the standard STI (Sexually Transmitted Infection) testing?

Standard STI Testing

All sexually active individuals should be screened for chlamydia, gonorrhea, syphilis, and HIV at minimum, with testing frequency and additional pathogens determined by age, sexual behaviors, and anatomic sites of exposure. 1

Core Testing Panel for All Sexually Active Individuals

Universal Screening Tests

• Chlamydia and gonorrhea using nucleic acid amplification tests (NAATs) are the foundation of STI screening due to their superior sensitivity and ability to use non-invasive specimens 2, 1
• Syphilis screening requires both a treponemal test (enzyme immunoassay or chemiluminescence) followed by a non-treponemal test (RPR) for confirmation using the reverse algorithm approach 2
• HIV testing should be offered to all sexually active persons aged 13-64 years seeking STI evaluation 2, 1

Specimen Collection Sites

• For women: Vaginal swab NAAT is preferred for chlamydia and gonorrhea; cervical specimens are acceptable for those under 25 years 2, 1
• For men: First-void urine NAAT is the standard approach for chlamydia and gonorrhea 3
• For men who have sex with men (MSM): Test all three anatomic sites—urogenital, rectal, and oropharyngeal—based on reported sexual practices 2, 1

Age and Risk-Based Screening Frequency

Women Under 25 Years

• Annual screening for chlamydia and gonorrhea is mandatory for all sexually active women in this age group due to higher infection rates from cervical immaturity and partner changes 1, 4
• Add trichomoniasis testing using vaginal swab NAAT (not wet mount, which has only 60-70% sensitivity) 2, 3

High-Risk Populations Requiring Every 3-6 Month Screening

• HIV-infected individuals with multiple partners, unprotected intercourse, methamphetamine use, or sex in conjunction with drug use 2, 1
• MSM with multiple or anonymous partners, drug use during sex, or partners with high-risk behaviors 2, 1, 4
• Commercial sex workers require comprehensive screening every 3-6 months including chlamydia, gonorrhea, syphilis, HIV, and trichomoniasis (for females) 3
• Persons who inject drugs need routine screening for all common STIs plus hepatitis C, even if injection occurred only once 1

Annual Screening for Moderate Risk

• All sexually active women aged 25 years or older with new or multiple partners, inconsistent condom use, or partners with high-risk behaviors 1, 4
• All sexually active men at increased risk based on sexual history 1

Pregnancy-Specific Testing

First Prenatal Visit (Universal)

• Hepatitis B surface antigen, HIV, and syphilis must be tested at the first prenatal visit for all pregnant women 2, 1
• Chlamydia and gonorrhea for pregnant women under 25 years or those at increased risk 2, 1

Third Trimester and Delivery

• Repeat syphilis testing in the third trimester and at delivery for high-risk women 2, 1
• No infant should be discharged without maternal syphilis status determined at least once during pregnancy and preferably again at delivery 2, 1
• Third trimester chlamydia screening for women under 25 or at increased risk to prevent neonatal infection 2

Post-Treatment Rescreening

Mandatory 3-Month Retest

• All patients treated for chlamydia or gonorrhea must be retested 3 months after treatment regardless of whether partners were treated, due to high reinfection rates of 25-40% 1, 3
• This is not optional—reinfection from untreated partners is the most common cause of persistent positive tests 2

Partner Management

Essential Components

• All sex partners of persons with STIs must be evaluated and treated to prevent reinfection 1
• Presumptive treatment for partners should be considered even before their test results return 1
• Partner notification can be performed by the patient, healthcare provider, or public health officials 1

Common Pitfalls to Avoid

• Do not rely on wet mount microscopy for trichomoniasis—it misses 30-40% of infections; use NAAT instead 2, 3
• Do not use Papanicolaou tests to diagnose trichomoniasis due to poor sensitivity and specificity 3
• Do not accept a single positive syphilis test as diagnostic—both treponemal and non-treponemal results plus clinical evaluation are required 3
• Do not assume previous negative tests provide ongoing protection—reassess sexual risk factors at every encounter 1
• Do not forget extragenital sites in MSM—rectal and pharyngeal infections are frequently asymptomatic and missed if only urogenital testing is performed 2
• Do not delay the mandatory 3-month post-treatment retest—this is when most reinfections are detected 1, 3

Reporting Requirements

• Syphilis, gonorrhea, and AIDS are reportable in every state 1
• Chlamydia is reportable in most states 1
• Clinicians must be familiar with local reporting requirements, which vary by jurisdiction 1