Clin Chem Lab Med. 2026 Jul 14. doi: 10.1515/cclm-2026-0463. Online ahead of print.
ABSTRACT
OBJECTIVES: Schistocyte quantification is essential for diagnosing microangiopathic hemolytic anemia (MAHA) and thrombotic microangiopathies (TMA). Early exclusion is critical for guiding appropriate management. However, the reference standard remains time-consuming manual microscopy, highly operator-dependent. In this study, the CellaVision Advanced RBC Application (ARBCA), an AI-based red blood cell morphology tool, was evaluated for schistocyte quantification in an emergency laboratory setting.
METHODS: A total of 169 peripheral blood smears were analyzed in two tertiary-care laboratories. ARBCA pre-classification counts were compared with post-classification review by two expert laboratory specialists, who used them as the reference standard, following ICSH criteria. Agreement was assessed with Bland-Altman analysis, Passing-Bablok regression, and Lin’s concordance correlation. Repeatability was evaluated on replicate smears, and diagnostic performance for MAHA was analyzed using ROC curves.
RESULTS: ARBCA showed overall agreement with expert results, with no significant systematic bias (mean difference 7.64 %; p=0.111). Passing-Bablok regression (slope 1.0; intercept 0.0) confirmed no proportional or constant error, except in MAHA cases, which deviated from linearity. Repeatability was acceptable (CV 8.0 %; IQR 2.80-12.40) and inter-rater agreement was high (κ=0.85). In MAHA patients, ARBCA underestimated schistocytes, misclassifying three cases. The optimal cutoff for MAHA prediction was ≥1.62 % (AUC 0.845; sensitivity 60.0 %, specificity 100.0 %), while expert review achieved an AUC of 1.00 with 100 % sensitivity and specificity.
CONCLUSIONS: ARBCA is a valuable screening tool that improves standardization, reproducibility, and turnaround time. However, expert morphological review remains essential, especially in emergencies where rapid and accurate decisions are lifesaving.
PMID:42443137 | DOI:10.1515/cclm-2026-0463