Should VDRL results be reported as 'negative' or 'non‑reactive', and how should HIV serology results be described?

Terminology for Reporting VDRL and HIV Test Results

Both VDRL and HIV test results should be reported as "non-reactive" or "reactive" rather than "negative" or "positive" in laboratory practice, as this terminology more accurately reflects the immunological nature of these serological tests and reduces confusion in clinical interpretation.

VDRL Reporting Standards

The standardized terminology for nontreponemal tests like VDRL uses "reactive" and "non-reactive" rather than positive/negative 1. This nomenclature is consistently used throughout the syphilis laboratory guidelines and reflects several important clinical realities:

• "Non-reactive" indicates no detectable antibody response at the tested dilution
• "Reactive" indicates presence of reagin antibodies, with titers reported (e.g., 1:16,1:32)
• This terminology acknowledges that results can revert from reactive to non-reactive after treatment 1
• It distinguishes between true infection and biological false-positive (BFP) reactions, which occur in 0.24-2.7% of tested populations 1

Clinical Context for VDRL Terminology

The term "non-reactive" is particularly important because:

• VDRL can become non-reactive after successful treatment, unlike treponemal tests which remain positive for life 2
• False-positive reactions occur with various conditions (HIV infection, HCV, malaria, drug use, recent vaccination) 1
• In neurosyphilis evaluation, CSF-VDRL may be initially negative even in true cases, particularly in HIV-positive patients 3, 4

HIV Reporting Standards

HIV serology should similarly be reported as "reactive" or "non-reactive" for screening tests, with subsequent confirmation required 2, 5:

• Initial screening: Fourth-generation HIV Ag/Ab combo tests report as "reactive" or "non-reactive"
• Confirmation required: A reactive result must be confirmed with a different assay before reporting HIV-positive status 5
• False-positive awareness: Even high signal-to-cutoff ratios (S/CO >400) can represent false-positive results requiring confirmatory testing 6

HIV Testing Algorithm

The proper reporting sequence follows this structure 2, 5:

1. Screening test reactive → Report as "reactive, confirmation pending"
2. Confirmatory test positive → Report as "HIV antibodies detected" or "HIV-positive"
3. Discordant results → Additional testing with different methodology required
4. Point-of-care confirmation can reduce anxiety and accelerate linkage to care when available 5

Common Pitfalls to Avoid

• Never report screening tests alone as "positive" without confirmation, as this can lead to significant psychological and clinical consequences 6
• Don't assume high S/CO ratios eliminate false-positives - even values >400 can be falsely reactive 6
• For VDRL: A non-reactive blood VDRL makes neurosyphilis extremely unlikely (negative predictive value >99%), so lumbar puncture may not be indicated 7
• In HIV-positive patients: Syphilis serology may show unusual responses, and biological false-positive VDRL rates are 10-fold higher (2.1% vs 0.24%) 1

Practical Implementation

Use this terminology consistently:

• Laboratory reports: "VDRL: Non-reactive" or "VDRL: Reactive at 1:32"
• HIV screening: "HIV Ag/Ab: Reactive" → followed by → "HIV-1/2 antibodies: Detected"
• Avoid: "VDRL negative," "HIV positive" without confirmation context

This standardized nomenclature improves communication between laboratories and clinicians, reduces misinterpretation, and appropriately conveys the need for confirmatory testing when indicated 2.