Atypical cells parameter in sysmex UN automated urine analyzer: a single center study

Abstract Objectives The literature about atypical cells in automated urine analyzers begins with the introduction of Sysmex UN. While modern urinalysis instruments report various kinds of epithelial cells, presence of atypical cells has not been considered. This study aims to observe the efficiency of the atypical cells parameter on Sysmex UN Automated Urine Analyzer with respect to customary manual urine cytology. Methods The patients with any indication for a cystoscopy examination were enrolled for the study between March 2022 and October 2022. Voided urine samples were gathered before the cystoscopy and bladder washing sampling was performed afterwards. Bladder washing samples were divided into two; one part was sent for urine cytology and the other was sent for urinalysis. Bladder biopsy was performed if cystoscopy evaluation was suspicious for malignancy. Results Thirty three patients (4 females and 29 males) underwent cystoscopy examination for suspicious bladder lesions and 15 of these patients were diagnosed as bladder cancer: nine were high-grade and six were low-grade bladder cancer due to their pathologic test results. Cytology examination results were negative for all patients. Using follow-up histologic diagnosis of urothelial carcinoma as a reference standard, the sensitivity of the atypical cells parameter on Sysmex UN was 27 %, specificity 78 %, positive predictive value 50 %, negative predictive value 56 %. Conclusions The results of this study confirmed the ability of Sysmex UN on detecting atypical cells in urine. Yet, the performance of the instrument needs to be improved before the parameter is presented for routine application.