RESUMEN
OBJECTIVE: To estimate the prevalence of unknown HIV infection in patients who consulted in hospital emergency services (ED) for conditions defined in the SEMES-GESIDA Consensus Document (DC), evaluate the efficiency of its im-plementation and investigate the efficiency of HIV serology determination in other conditions. METHODS: Results were reviewed in 10 Catalan EDs for 12 months (July-21-June-22) after implementing CD recommendations: request HIV serology in case of suspected sexually transmitted infection, chemsex, post-exposure prophylaxis (PEP), mononucleosis syndrome, community pneumonia (18-65 y-o) or herpes zoster (18-65 y-o). Other reasons for request were included. Prevalence (%) of global seropositivity and for each circumstance was calculated, with a 95% confidence interval (95%CI). The efficient strategy was considered if the lower limit of the CI95%>0.1%. RESULTS: A total of5,107 HIV serologies were performed: 2,847(56%) in situations specified in CD, and 2,266 (44%) in other 138 circumstances. Forty-eight unknown HIV infections were detected (prevalence=0.94%;95%CI=0.69-1.24). The prevalence was somewhat higher in DC requests (30 cas-es 1.12%) than the rest (18 cases 0.71%; p=0.16). The individualized prevalence of CD reasons ranged between 7.41% (95%CI=0.91-24.3) in chemsex and 0.42% 95%CI=0.14-0.98) in PPE, always efficient except herpes zoster (0.76%; CI95%=0.02-4.18). In other reasons, cases were detected in 12 circumstances, and in four the determination could be efficient: lymphopenia (10%;CI95%=0.25-44.5), fever with polyarthralgia-polyarthritis (7.41%;CI95% =0.91-24.3), behavioral alteration-confusion-encephalopathy (3.45%;95%CI=0.42-11.9) and fever of unknown origin (2.50%;95%CI=0.82-5.74). CONCLUSIONS: The determination of HIV serology in HES in the processes defined by DC SEMES-GESIDA is efficient. Some circumstances are identified that could be added to those previously contemplated to increase efficiency.