Background. Overcrowding in emergency departments (EDs), particularly pediatric emergency departments (PEDs), remains a significant challenge that affects patient outcomes and the efficiency of healthcare. Rapid diagnostic tests (RDTs) for respiratory viruses could be a promising tool for improving patient management by enabling prompt etiological diagnoses. This study investigated whether positive RDT results for influenza or adenovirus were associated with differences in length of stay (LOS) in a tertiary PED during epidemic seasons. Methods. A retrospective cohort study was conducted at IRCCS Istituto Giannina Gaslini, Genoa, Italy, over two epidemic seasons (December–February, 2023–2025). All consecutive pediatric patients presenting with fever and respiratory symptoms who underwent rapid diagnostic testing for influenza and/or adenovirus during two epidemic seasons were included. LOS was assessed as the time from triage to discharge (TTD) and from physician assignment to discharge (ATD). Patients were stratified by positive versus negative RDT results. Analyses between groups used the Mann–Whitney U-test for continuous variables and chi-square or Fisher’s exact test for categorical variables. A two-tailed p-value < 0.05 was considered significant. Results. Of the 1238 patients analyzed, the median age was 3.3 years (IQR 1.4–7.2), with male predominance (58.1%). A total of 330 patients (26.6%) tested positive. Compared with negative results, positive RDTs were associated with shorter median TTD (217.0 vs. 239.0 min, p < 0.001) and ATD (66.0 vs. 148.5 min, p < 0.001), which was consistent in both the influenza and adenovirus subgroups. No significant difference in 72 h readmission rates was observed between groups. Conclusions. Among children tested with RDTs for influenza and adenovirus, positive results were associated with reduced PED LOS without increasing early return visits. While these findings suggest a potential role in supporting patient flow, conclusions regarding the broader impact on PED overcrowding should be drawn with caution. Further prospective studies, including non-tested controls and additional viral targets, are required.

Background: Respiratory tract infections (RTIs) represent one of the most prevalent reasons for visits to Pediatric Emergency Departments (PEDs). Because viral and bacterial presentations frequently overlap, a substantial proportion of antibiotic prescriptions in pediatric acute care are potentially unnecessary, contributing to antimicrobial resistance. Rapid Diagnostic Tests (RDTs) for respiratory viruses have been suggested as tools to enhance diagnostic precision and support antimicrobial stewardship. However, evidence regarding their real-world impact in pediatric emergency settings is limited. Objectives: This study aimed to assess the association between point-of-care RDT results and antibiotic management in a tertiary PED, focusing on both the discontinuation of antibiotics in children already receiving treatment and the avoidance of new antibiotic prescriptions in untreated children. The secondary objective was to evaluate the short-term safety through 72-h return visits. Methods: A retrospective cohort study was conducted at a tertiary PED during two epidemic seasons (December–February 2023–2024 and 2024–2025). Children aged <18 years who underwent RDTs for febrile respiratory illnesses were included. Patients were stratified based on whether they were already receiving antibiotic therapy at presentation. The primary outcomes were antibiotic discontinuation among treated patients and initiation among untreated patients. Unplanned return visits to the PED within 72-h post-discharge were used as a pragmatic short-term safety outcome to capture early clinical deterioration. RDTs (SD Biosensor Standard F Antigen) were performed at the bedside with a turnaround time of 10–15 min. Results: A total of 1238 children were included, of whom 330 (26.6%) tested positive for influenza and/or adenovirus. Among the 234 children already receiving antibiotics, discontinuation was significantly more frequent in the RDT-positive group (p < 0.001; OR 0.044). Among the 1004 untreated children, antibiotic prescription was significantly lower in the positive group than in the negative group (p < 0.001; OR 0.097). Return visits within 72-h did not differ between the groups in either cohort. No invalid tests occurred. Conclusions: Influenza/adenovirus RDT positivity was associated with lower antibiotic initiation among untreated children and higher discontinuation among those already receiving antibiotics, with no differences in 72-h return visits. These findings suggest a potential role for bedside viral testing as a decision-support tool for antibiotic management in the PED.