What tests are included in a standard sexually transmitted disease (STD) screening panel?

Standard STD Panel Components

A comprehensive STD screening panel includes nucleic acid amplification tests (NAATs) for chlamydia and gonorrhea, serologic testing for syphilis (using both treponemal and non-treponemal tests), and HIV testing (preferably fourth-generation antigen/antibody combination test). 1

Core Testing Components

Bacterial STI Testing

• Chlamydia trachomatis and Neisseria gonorrhoeae are tested simultaneously using NAATs, which represent the gold standard due to superior sensitivity compared to culture (96-100% sensitivity for chlamydia, 97-100% for gonorrhea). 2, 1
• For women, vaginal swab NAATs are preferred over cervical specimens or urine, with vaginal swabs detecting 86% of infections compared to only 63% for first-void urine. 3
• For men who have sex with men (MSM), testing must include all three anatomic sites—urogenital, rectal, and oropharyngeal—based on reported sexual practices, as over 60% of gonococcal and 80% of chlamydial infections in MSM would be missed if only urogenital sites were tested. 2, 1, 4

Syphilis Screening

• Reverse algorithm syphilis testing starts with a treponemal-specific test (T. pallidum antibody via immunoassay), followed by non-treponemal testing (RPR) to confirm active disease. 1
• Both test components are necessary because treponemal tests remain positive for life after infection, while non-treponemal tests indicate active disease and treatment response. 2

HIV Testing

• Fourth-generation HIV testing combines detection of both HIV antibodies and p24 antigen, allowing detection 2-4 weeks post-exposure versus 3-6 weeks for antibody-only tests. 1
• HIV testing is recommended for all sexually active persons aged 13-64 years seeking STI evaluation. 1

Additional Testing Based on Risk Factors

Trichomoniasis

• Vaginal swab NAAT for Trichomonas vaginalis should be included for women under 25 years or those with multiple partners, history of STIs, or high-risk behaviors. 1
• Wet mount microscopy misses 30-40% of infections and should not be relied upon as the primary diagnostic method. 1

Hepatitis B

• Hepatitis B surface antigen (HBsAg) testing is included for all pregnant women at the first prenatal visit and for persons at increased risk (injection drug use, multiple partners, concurrent STDs). 2, 5

Hepatitis C

• Hepatitis C screening is recommended for all persons who inject drugs, even if only once. 1

Population-Specific Modifications

Pregnant Women

All pregnant women require universal screening at the first prenatal visit for: 2, 5

• Syphilis serology (with repeat testing in third trimester and at delivery for high-risk women)
• Hepatitis B surface antigen
• HIV testing
• Chlamydia and gonorrhea if under 25 years or at increased risk

HIV-Positive Individuals

HIV-infected persons require screening every 3-6 months for all bacterial STIs (chlamydia, gonorrhea, syphilis, trichomoniasis) due to increased HIV transmission risk when co-infected. 1

Men Who Have Sex with Men

MSM with multiple or anonymous partners, methamphetamine use, or sex in conjunction with drug use require comprehensive screening every 3-6 months including: 1

• Urogenital, rectal, and oropharyngeal NAATs for chlamydia and gonorrhea
• Syphilis serology
• HIV testing

Tests NOT Included in Standard Panels

Herpes Simplex Virus (HSV)

HSV screening is explicitly NOT recommended for asymptomatic patients, as there is no evidence that treating asymptomatic HSV improves outcomes. 1 Testing is only performed when lesions are present or symptoms suggest active infection.

Human Papillomavirus (HPV)

There is no HPV blood test; HPV testing is only performed via cervical/anal cytology or direct visualization of lesions. 1 HPV is not part of routine STD screening panels.

Common Pitfalls to Avoid

• Never rely on urine specimens alone for women—vaginal swabs detect 23% more infections than first-void urine. 3
• Do not skip extragenital site testing in MSM—rectal and pharyngeal infections are frequently asymptomatic and represent the majority of infections in this population. 1, 4
• Avoid using wet mount microscopy as the sole test for trichomoniasis—NAAT should be used instead due to 30-40% false-negative rate with microscopy. 1
• Remember that culture for gonorrhea and chlamydia is significantly less sensitive than NAATs (culture sensitivity for rectal gonorrhea is only 23.8% compared to 100% for NAATs). 6, 4

Mandatory Post-Treatment Follow-Up

All patients treated for chlamydia or gonorrhea require retesting at 3 months, regardless of whether partners were treated, due to reinfection rates of 25-40%. 1 This is not optional screening—it is a mandatory component of STD management.