Different approaches to HIV confirmation: a survey of three Italian regions

Accurate HIV diagnosis is critical to achieving global targets for ending the AIDS epidemic. Despite international recommendations, HIV confirmatory testing in Italy remains poorly standardized.

This study aimed to evaluate current HIV confirmation algorithms used in public laboratories across three Italian regions and suggest improvements for harmonization.

Within the PRONTI project, we surveyed 31 second-level HIV laboratories in Piemonte, Toscana, and Puglia, representing 20% of the Italian population. Laboratory directors were interviewed using a structured questionnaire on first line and confirmatory assays, algorithm steps, and use of immunoblots (IB) and HIV-RNA testing.

All laboratories employed 4th-generation Ag/Ab immunoassays for initial screening. Four confirmatory algorithms were identified: (1) IB followed by HIV-RNA if IB negative/indeterminate (42%); (2) repeat 4th-generation assay, then IB and HIV-RNA if needed (36%); (3) direct HIV-RNA testing (16%); and (4) HIV-RNA followed by IB if RNA negative/inconclusive (6%). IB was used in all laboratories in different ways, and HIV-RNA testing in 87% of laboratories. Algorithms varied significantly by region, reflecting decentralized healthcare governance.

HIV confirmation practices in Italy remain heterogeneous, with frequent reliance on IB despite recent international trends favoring molecular approaches. Algorithms prioritizing HIV-RNA testing offer faster results, reduce patient anxiety, limit HIV transmission and improve linkage to care, though IB remains useful in selected cases. National guidelines are urgently needed to standardize HIV diagnostic workflows and optimize resource use.