Performance evaluation of a new and improved cuvette-based automated urinalysis analyzer with phase contrast microscopy.

Abstract Background The use of phase contrast in urinalysis has been highly recommended. A new system, sediMAX conTRUST PRO, is now available providing simultaneous automated phase contrast and bright field microscopy. This study aimed to evaluate both analytical and diagnostic performance of this new analyzer. Methods Results from 504 samples evaluated with the sediMAX conTRUST PRO were compared to those obtained from the same samples by manual microscopy (MM). Analytical and diagnostic performance were assessed according to established guidelines. Results The concentration of red blood cells (RBCs)and white blood cells (WBCs) at which the LoQ satisfied a CV< 25% was 12 particles per μL (p/μL) and 8 p/μL, respectively. Within one grade of agreement concordance was quite high, 97.8% for RBCs and 98.0% for WBCs, and above 90% for all other particles. Overall, diagnostic sensitivity and specificity were good (>80%) for the particles considered, although lower sensitivities, 70.6% and 61.8%, were respectively found for hyaline and pathological casts. Conclusions The sediMAX conTRUST PRO provides very good performance in terms of RBC and WBC recognition and enumeration, and quite good performance for all other particles. Hyaline cast and pathological cast identification is fine and comparable to other automated systems, but could use further improvement. Highlights • Best urine sediment evaluation is by phase contrast and bright field microscopy. • sediMAX conTRUST PRO provides good precision for quantitative particles. • High concordance of results between sediMAX conTRUST PRO and manual microscopy • Diagnostic sensitivity and specificity was >80% for all particles with the analyzer [ABSTRACT FROM AUTHOR]