What are the recommended tests and treatments for STD screening?

STD Screening: Recommended Tests and Treatments

Core Screening Panel

All sexually active individuals require risk-stratified screening for chlamydia, gonorrhea, HIV, and syphilis, with the specific tests and frequency determined by age, sexual behaviors, and population risk factors. 1

Standard Tests for Most Populations

• Chlamydia and gonorrhea testing using nucleic acid amplification tests (NAATs) should be performed annually for all sexually active women under 25 years and for older women with risk factors including new or multiple partners 1, 2
• HIV testing should be offered to all sexually active persons aged 13-64 years, with more frequent testing (every 3-6 months) for those with ongoing high-risk behaviors 1, 2
• Syphilis screening requires both a treponemal test and non-treponemal test using the reverse algorithm approach for individuals with high-risk sexual behavior 1, 2
• Hepatitis B surface antigen testing should be performed for high-risk individuals and all pregnant women 3, 2

Specimen Collection Sites

• For women, vaginal swab NAAT is the preferred specimen for chlamydia and gonorrhea, though cervical specimens are acceptable 1
• 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 extragenital infections are frequently asymptomatic 1, 2
• Urine samples and self-obtained swabs facilitate screening in nonmedical settings 3

Population-Specific Screening Algorithms

Pregnant Women (Universal Screening Required)

• First prenatal visit: Screen all pregnant women for hepatitis B surface antigen, HIV, and syphilis 3, 1, 4
• First prenatal visit: Screen for chlamydia and gonorrhea if under 25 years or at increased risk 3, 1, 4
• Third trimester: Repeat syphilis testing for high-risk women 3, 1, 4
• At delivery: Repeat syphilis testing for high-risk women, and no infant should be discharged without determination of maternal syphilis status 3, 1

High-Risk Populations Requiring Frequent Testing

• HIV-infected individuals: Screen every 3-6 months for chlamydia, gonorrhea, and syphilis if they have multiple partners, unprotected intercourse, methamphetamine use, or sex in conjunction with drug use 3, 1
• Men who have sex with men (MSM): Screen every 3-6 months for chlamydia, gonorrhea, syphilis, and HIV if they have multiple or anonymous partners, drug use during sex, or partners with high-risk behaviors 1, 2
• Persons entering correctional facilities: Screen for syphilis, gonorrhea, and chlamydia within the first 24 hours, with additional screening for trichomoniasis and bacterial vaginosis in females when possible 3
• Adolescents in institutional settings: Screen for gonorrhea and chlamydia at every visit if prevalence is ≥2% 3

Risk Factors That Trigger Screening

• New sex partners or more than one sex partner 1
• A sex partner with concurrent partners or who has an STI 1
• Inconsistent condom use among persons not in mutually monogamous relationships 1
• Previous or coexisting STI 1
• Exchanging sex for money or drugs 1
• Incarceration 1
• Living in communities with high STI prevalence 1

Screening Frequency Based on Risk

• Annual screening is appropriate for most at-risk populations including sexually active women under 25 years 1, 2
• Every 3-6 months for individuals with ongoing high-risk behaviors including HIV-infected persons and MSM with multiple partners 1, 2
• Screening should occur at least yearly for persons with HIV/AIDS if any potential risk exists for STD acquisition, with more frequent screening if incident STDs are detected 3

Post-Treatment Management

Mandatory Retesting

• All patients treated for chlamydia or gonorrhea must be retested 3 months after treatment regardless of whether they believe their partners were treated, due to reinfection rates of 25-40% 1, 2
• This 3-month retest is mandatory and non-negotiable, as it detects reinfection rather than treatment failure 1

Partner Management

• Sex partners of persons with STIs should be evaluated and treated, with consideration of presumptive treatment for partners of persons with curable STIs 1
• Partner notification can be performed by the patient, healthcare provider, or public health officials 1
• Persons with HIV/AIDS and a new STD require intensive counseling about eliminating unprotected sex and assisting with partner notification 3

Treatment Considerations for Pregnant Women

Pregnant women with STDs require specific antimicrobial regimens that differ from non-pregnant patients to prevent devastating fetal outcomes while avoiding teratogenic agents. 4

Syphilis in Pregnancy

• Parenteral penicillin G is the only proven effective treatment and must be given at least 1 month before delivery to prevent congenital infection 4
• Women with penicillin allergy must be desensitized and treated with penicillin, as no alternative regimens adequately treat fetal infection 4

Chlamydia in Pregnancy

• Azithromycin 1 gram orally as a single dose is the preferred treatment, offering superior compliance and proven safety 4
• Doxycycline is absolutely contraindicated in pregnancy 4

Gonorrhea in Pregnancy

• Ceftriaxone 125-250 mg intramuscularly plus azithromycin 1 gram orally treats gonorrhea while addressing frequent chlamydial co-infection 4
• Fluoroquinolones are contraindicated in pregnancy 4

Reporting Requirements

• Syphilis, gonorrhea, and AIDS are reportable in every state 3, 1
• Chlamydial infection is reportable in most states 1
• Clinicians should be familiar with local STD reporting requirements and report cases in a timely manner 3, 1

Common Pitfalls to Avoid

• Never rely on wet mount microscopy for trichomoniasis, as it misses 30-40% of infections; NAAT should be used instead 1
• Never fail to test extragenital sites in MSM, as rectal and pharyngeal infections are frequently asymptomatic and missed if only urogenital testing is performed 1
• Never assume a previous negative test provides ongoing protection; reassess sexual risk factors at each clinical encounter 1
• Never use doxycycline, tetracyclines, or fluoroquinolones in pregnant women, as these are absolutely contraindicated 4
• Never treat penicillin-allergic pregnant women with syphilis using alternative antibiotics; desensitization is mandatory 4
• Never discharge an infant without determining the mother's syphilis status at least once during pregnancy and preferably at delivery 3, 1