Clinical decision limits as criteria for setting analytical performance specifications for laboratory tests

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Laboratoriotutkimusten viitearvojen määrittäminen ja merkitys kliinisessä päätöksenteossa

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Kustannushyöty on kokonaisuus

Vastine Esa Sopen ja Ville Kailan kommentteihin SLL 71(20):1436-1437, 201

UriSed 3 PRO automated microscope in screening bacteriuria at region-wide laboratory organization

Background and aims: We assessed the possibility to rule out negative urine cultures by counting with UriSed 3 PRO (77 Elektmnika, Hungary) at Helsinki and Uusimaa Hospital District. Materials and methods: Bacteria counting of the UriSed 3 PRO automated microscope was verified with reference phase contrast microscopy against growth in culture. After acceptance into routine, results of bacteria and leukocyte counting from 56 426 specimens with eight UriSed 3 PRO instruments were compared against results from parallel samples cultured on chromogenic agar. Laboratory data including preanalytical details were accessed through the regional database of the Helsinki and Uusimaa Hospital District. Results: A combined sensitivity of 87-92% and a negative predictive value of 90-96% with a specificity of 54-50% was reached, depending on criteria. Preanalytical data (incubation time in bladder) combined with the way of urine collection would improve these figures if reliable. Conclusions: Complex patient populations, regional logistics and data interfases, and economics related to increased costs of additional particle counts against costs of screening cultures of all samples, did not support adaptation of a screening process of urine cultures. This conclusion was made locally, and may not be valid elsewhere.Peer reviewe

Randomised Trial of Adjuvant Radiotherapy Following Radical Prostatectomy Versus Radical Prostatectomy Alone in Prostate Cancer Patients with Positive Margins or Extracapsular Extension

Background: It remains unclear whether patients with positive surgical margins or extracapsular extension benefit from adjuvant radiotherapy following radical prostatectomy. Objective: To compare the effectiveness and tolerability of adjuvant radiotherapy following radical prostatectomy. Design, setting, and participants: This was a randomised, open-label, parallel-group trial. A total of 250 patients were enrolled between April 2004 and October 2012 in eight Finnish hospitals, with pT2 with positive margins or pT3a, pN0, M0 cancer without seminal vesicle invasion. Intervention: A total of 126 patients received adjuvant radiotherapy at 66.6 Gy. Outcome measurements and statistical analysis: The primary endpoint was biochemical recurrence-free survival, which we analysed using the Kaplan-Meier method and Cox proportional hazard regression. Overall survival, cancer-specific survival, local recurrence, and adverse events were secondary endpoints. Results and limitations: The median follow-up time for patients who were alive when the follow-up ended was 9.3 yr in the adjuvant group and 8.6 yr in the observation group. The 10-yr survival for biochemical recurrence was 82% in the adjuvant group and 61% in the observation group (hazard ratio [HR] 0.26 [95% confidence interval {CI} 0.14-0.48], p <0.001), and for overall survival 92% and 87%, respectively (HR 0.69 [95% CI 0.29-1.60], p = 0.4). Two and four metastatic cancers occurred, respectively. Out of the 43 patients with biochemical recurrence in the observation group, 37 patients received salvage radiotherapy. In the adjuvant group, 56% experienced grade 3 adverse events, versus 40% in the observation group (p = 0.016). Only one grade 4 adverse event occurred (adjuvant group). A limitation of this study was the number of patients. Conclusions: Adjuvant radiotherapy following radical prostatectomy is generally well tolerated and prolongs biochemical recurrence-free survival compared with radical prostatectomy alone in patients with positive margins or extracapsular extension. Patient summary: Radiotherapy given immediately after prostate cancer surgery prolongs prostate-specific antigen progression-free survival, but causes more adverse events, when compared with surgery alone. (C) 2019 European Association of Urology. Published by Elsevier B.V. All rights reserved.Peer reviewe

Virtsan perustutkimusten pikadiagnostiikka

Vertaisarvioitu. English summar

Verification of UriSed 3 PRO automated urine microscope in regional laboratory environment

Background and aims: Ten UriSed 3 PRO automated microscopes (77 Elektronika, Hungary) were verified for nine HUSLAB laboratories with 160 000 annual urine samples. Materials and methods: Particle counting of the primary UriSed 3 PRO instrument (77 Elektronika, Hungary) was verified against reference visual microscopy with 463 urine specimens, and against urine culture on chromogenic agar plates with parallel 396 specimens. Nine secondary instruments were compared pairwise with the primary instrument. Results: Relative imprecisions compared to Poisson distribution, R(CV), were estimated to be 1.0 for white blood cell (WBC) and 1.5 for red blood cell (RBC) counts, respectively. Spearman's correlations against visual microscopy were rS = 0.94 for WBC, rS = 0.87 for RBC, and rS = 0.82 for squamous epithelial cell (SEC) counts. Agreement with visual microscopy (Cohen's weighted kappa) was 0.94 for WBC, 0.89 for RBC, 0.88 for SEC, 0.59 for combined casts, and 0.49 for non-squamous epithelial cells (NEC). Bacteria were detected with a sensitivity of 90% and specificity of 39 against culture at 107 CFB/L (104 CFU/mL). Created flagging limits allowed automated reporting for 70-75% of patient results. Conclusions: UriSed 3 PRO instruments were adopted into routine use after acceptance of the verification.Peer reviewe