Clinical Scenario:
An 8-year-old boy is brought to the pediatric clinic for HIV testing. He has no previous HIV test result. The first HIV rapid test (A1) is reactive. A second rapid test using a different assay (A2) is performed according to the HIV testing algorithm and is non-reactive.
According to the WHO HIV testing strategy for children aged ≥18 months, what is the next step?
A. Report HIV-negative
B. Start ART
C. Repeat A1
D. Perform A3
E. Repeat testing after 14 days
Correct answer & Explanation:
Correct answer: C. Repeat A1
Explanation
The child has a discordant HIV testing result: A1 reactive and A2 non-reactive (A1+ / A2−).
For individuals 18 months or older, WHO recommends sequential testing using different assays. When the first assay is reactive, a second distinct assay is performed. If the second assay is non-reactive, the first assay should be repeated.
The subsequent result determines the final interpretation:
- A1+ → A2− → repeat A1−: report HIV-negative.
- A1+ → A2− → repeat A1+: report HIV-inconclusive and ask the patient to return for retesting after 14 days.
An A3 is not indicated at this stage. A third assay is used when both A1 and A2 are reactive (A1+ / A2+).
Important: A reactive first rapid test is not by itself an HIV-positive diagnosis. The recommended testing algorithm must be completed before assigning an HIV-positive status.
Reference:
World Health Organization. Consolidated guidelines on HIV prevention, testing, treatment, service delivery and monitoring. WHO. The WHO algorithm specifically recommends repeating A1 when A1+ / A2− occurs in individuals aged ≥18 months
