Diagnostic Utility of the Sysmex UF-5000 Flow Cytometer in Acute Bacterial Prostatitis: A Retrospective Pilot Study

Purpose: To evaluate the diagnostic performance of the Sysmex UF-5000 flow cytometer in detecting acute bacterial prostatitis (ABP) compared to standard urine culture.Materials and Methods: This retrospective study analyzed 45 urine samples from patients with a clinical diagnosis of ABP. Each sample was evaluated using the UF-5000 to measure red blood cells (RBC), white blood cells (WBC), and bacterial counts, and the results were compared with those from standard urine culture and Gram staining. Receiver operating characteristic curves were generated, and sensitivity, specificity, positive predictive value (PPV), and negative predictive value were determined. Concordance between Gram classification by the UF-5000 and conventional Gram staining was also evaluated.Results: Of the 45 patients, 84.4% had positive urine cultures. The bacterial count parameter demonstrated the highest diagnostic performance (area under the curve AUC=0.79; sensitivity, 89.5%; PPV, 91.9%), outperforming WBC (AUC=0.76) and RBC (AUC=0.55). The Gram classification flag showed an overall concordance of 85.7% with conventional Gram staining, with a concordance rate of 88% for Gram-negative organisms.Conclusions: The Sysmex UF-5000 exhibited good concordance with urine culture for patients with ABP, particularly through the bacterial count parameter. Although it does not replace culture, the UF-5000 may serve as a rapid adjunctive tool to support early clinical decision-making in suspected ABP cases.