Three settings, one goal: Performance of different HIV testing strategies at a tertiary centre in Milan

Timely HIV diagnosis remains suboptimal in Italy. The aims of this study are to assess how inpatient, outpatient and community HIV testing strategies differ in diagnostic yield, testers' demographics, immuno-virological status at diagnosis and linkage to care.

This is a cross-sectional analysis of all individuals tested for HIV in 2024-2025 at San Raffaele Hospital (Milan, Italy) through: (i) HIV-HOTE (NCT06282328), an inpatient, indicator-condition and behaviour-triggered testing study in medical and surgical wards; (ii) EasyTest, a community-based, rapid testing programme in territorial clinics and outreach events; and (iii) a hospital-based walk-in outpatient HIV/sexually transmitted infection (STI) clinic. Demographics and HIV test results are described across strategies.

Overall, 4604 individuals were tested for HIV (inpatients n = 300; outpatients n = 2913; community n = 1391), with 43 new HIV diagnoses. Inpatient testers were older (median 54 vs. 35.1-36.2 years), more frequently women (38.0% vs. 11.7-35%) and less frequently men who have sex with men (10.7% vs. 77.7-36.4%) compared to outpatient and community-based testers. People with a reactive HIV test were 2% (6/300) among inpatients, 1.17% (34/2913) in the outpatient clinic and 0.22% (3/1391) in the community programme. Among people with newly diagnosed HIV, median CD4⁺ count at diagnosis was 540 cells/μL for inpatients, 460 cells/μL for outpatients and 198 cells/μL for community testers. Linkage to care was 100% across all strategies.

Within a single tertiary Italian centre, HIV inpatient indicator-condition testing, a hospital walk-in pathway and a community point-of-care service tested distinct populations. A blended HIV testing model is essential to maximize HIV case-finding.