Challenges in HIV Diagnosis Algorithm: Experience of the Confirmation Laboratory

Area of Science:

• Clinical diagnostics
• Virology
• Public health

Background:

• Current HIV diagnostic algorithms rely on screening and confirmatory tests.
• Variations in implementation and clinician ordering practices can impact diagnostic accuracy and timeliness.

Purpose of the Study:

• To evaluate the effectiveness of the existing HIV diagnostic algorithm.
• To propose an improved algorithm for rapid HIV diagnosis.

Main Methods:

• Retrospective analysis of 82,882 serum samples using Architect HIVAg/Ab for screening.
• Geenius HIV1/2 and Artus HIVirus-1 QS-RGQ for confirmation.
• HIV-1 RNA testing utilized for specific cases.

Main Results:

• 262 samples (0.3%) were reactive on initial screening.
• 51% of reactive samples were confirmed positive for HIV-1 antibodies.
• 5 cases of acute HIV-1 infection were identified through HIV-1 RNA testing in samples with initially negative antibody confirmation.
• 16 false-reactive screening results were identified by clinicians.
• Geenius assay showed indeterminate results in 1.45% of samples.

Conclusions:

• The current HIV diagnostic algorithm was not fully implemented, particularly regarding clinician-ordered HIV-1 RNA PCR.
• Implementing HIV-1 RNA PCR as a reflex test for specific reactive samples could reduce unnecessary confirmatory testing and prevent loss to follow-up.
• An optimized algorithm incorporating reflex HIV-1 RNA PCR can shorten diagnosis turnaround time and improve patient care.