What is the recommended testing and treatment protocol for a patient concerned about their HIV status?

HIV Testing Protocol

All persons aged 13-65 years should undergo routine opt-out HIV screening at least once in their lifetime using a fourth-generation antigen/antibody combination assay, with high-risk individuals tested every 3 months. 1, 2, 3

Universal Screening Approach

Routine opt-out screening is recommended for all patients aged 13-64 years in all healthcare settings including primary care, emergency departments, urgent care, STD clinics, TB clinics, substance abuse treatment centers, and correctional facilities. 4, 1, 2

• Patients should be informed orally or in writing that HIV testing will be performed unless they decline—no separate written consent is required beyond general medical consent. 4, 3
• Prevention counseling is not mandatory as part of routine screening programs. 4
• Screening should be initiated unless HIV prevalence is documented to be <0.1% or diagnostic yield is <1 per 1,000 patients screened. 4, 3

This universal approach is critical because risk-based screening has failed to identify 10-25% of HIV-positive individuals who report no high-risk behaviors, and even when risk factors are documented, only one-third of at-risk patients actually receive testing. 1

High-Risk Populations Requiring Frequent Testing

The following groups require HIV testing every 3 months as long as risk continues: 1, 2

• Men who have sex with men (MSM) and transfeminine persons
• People who inject drugs and their sex partners
• Persons who exchange sex for money or drugs
• Sex partners of HIV-infected persons
• Persons newly diagnosed with sexually transmitted infections or hepatitis C
• Persons with multiple sex partners or whose partners have multiple partners

Optimal Testing Algorithm

Initial Screening Test

Use a fourth-generation HIV antigen/antibody combination assay that detects both HIV antibodies and p24 antigen. 1, 2, 3 This approach detects acute infection approximately 11-14 days post-exposure, roughly 2 weeks earlier than third-generation antibody-only tests. 5, 6, 7

Confirmatory Testing Pathway

If the initial fourth-generation assay is reactive: 2, 3

1. Perform HIV-1/HIV-2 antibody differentiation immunoassay to distinguish between HIV-1 and HIV-2 infections. 2, 3

2. If differentiation assay is positive: HIV infection is confirmed—proceed immediately to baseline evaluation and treatment initiation. 2, 3

3. If differentiation assay is negative or indeterminate: Perform nucleic acid amplification testing (NAAT/HIV RNA) to rule out acute HIV-1 infection. 2, 3

Critical caveat: A diagnostic window can occur even with fourth-generation assays when p24 antigen declines below detection limits before antibodies develop, potentially causing false-negative results during early infection. 5 This reinforces the need for HIV RNA testing when acute infection is suspected clinically.

Special Testing Situations

When acute retroviral syndrome is suspected (fever, lymphadenopathy, pharyngitis, rash within 2-4 weeks of high-risk exposure), use both a fourth-generation assay AND plasma HIV RNA test simultaneously. 4, 3

For recent high-risk exposure within 72 hours: Perform both laboratory-based antigen/antibody test and HIV RNA testing—avoid oral fluid-based rapid tests as they are less sensitive for acute infection. 3

All patients initiating tuberculosis treatment should be screened routinely for HIV. 4

All patients seeking STD treatment should be screened for HIV at each visit for a new complaint, regardless of known or suspected risk behaviors. 4

Post-Diagnosis Baseline Evaluation

Before initiating antiretroviral therapy, obtain the following tests immediately: 1, 2, 3

• HIV RNA viral load
• CD4 cell count with percentage
• Genotypic resistance testing (for NRTI and NNRTI resistance)
• HLA-B*5701 testing (required before abacavir use)
• CCR5 tropism testing (if considering maraviroc)
• Screening for coinfections: hepatitis B, hepatitis C, tuberculosis, sexually transmitted infections
• Baseline renal and hepatic function tests

Treatment Initiation

All persons diagnosed with HIV should be offered antiretroviral therapy immediately upon diagnosis, regardless of CD4 count or viral load. 4, 1, 2 This represents a critical shift from older guidelines that delayed treatment based on CD4 thresholds.

Preferred initial regimens include an integrase strand transfer inhibitor (INSTI) plus two nucleoside reverse transcriptase inhibitors (NRTIs). 2

Monitoring During Treatment

Viral load monitoring schedule: 4, 1, 2

• Measure at 4-6 weeks after starting or changing ART regimen
• Every 3 months until HIV RNA <50 copies/mL for at least 1 year
• Every 6 months after achieving 1 year of viral suppression with consistent adherence

CD4 count monitoring: 4, 1, 2

• Every 6 months until counts are >250/μL for at least 1 year with concomitant viral suppression
• Can be discontinued once this threshold is maintained

If viral load remains detectable or rebounds: Confirm the result within 4 weeks, assess adherence, and perform genotypic resistance testing if adherence appears adequate. 4

Result Communication

Negative results may be conveyed without direct personal contact. 3

Positive results must be communicated confidentially through personal contact by a clinician, nurse, or mid-level practitioner—never use family or friends as interpreters due to stigma risk. 3

Active efforts are essential to ensure HIV-infected patients receive results and immediate linkage to clinical care, counseling, and prevention services. 4, 3

Comprehensive Care Components

Behavioral and psychosocial services are integral to HIV care and should be available on-site or through referral. 4, 1, 2

Routine screening and treatment for depression is recommended for all HIV-infected patients. 1, 2

Age- and risk-appropriate screening at each visit for: 1

• Sexually transmitted infections at various anatomical sites
• Anal or cervical dysplasia
• Tuberculosis
• General health and medication toxicity

Partner notification: Strongly encourage patients to disclose their HIV status to spouses, current and previous sex partners, and recommend partner testing—health departments can assist with confidential partner notification. 4

Common Pitfalls to Avoid

Do not rely solely on patient-reported risk behaviors—many infected individuals either don't recognize their risk or won't disclose behaviors. 1

Do not delay testing in low-prevalence settings—screening is cost-effective even at prevalence as low as 0.1-0.2%. 1

Do not use oral fluid-based rapid tests for post-exposure prophylaxis evaluation—they are significantly less sensitive for acute infection than blood-based fourth-generation assays. 3

Be aware that fourth-generation rapid point-of-care tests have lower sensitivity than laboratory-based fourth-generation assays, particularly for detecting p24 antigen in acute infection. 8, 9