VERIFICATION OF THE XPERT® BCR-ABL ULTRA P190 GENEXPERT – CEPHEID KIT FOR IMPLEMENTATION IN ROUTINE ONCOHEMATOLOGICAL TESTING IN A DIAGNOSTIC LABORATORY SERVICE

Introduction: Acute lymphoblastic leukemia (ALL) is a hematological malignancy associated with the t(9;22) translocation, which leads to the formation of the Philadelphia chromosome (Ph+) and the BCR::ABL1 fusion gene. The p190 transcript is related to a high-risk subtype, directly impacting prognosis and therapeutic management. Therefore, rapid and sensitive molecular detection is essential for diagnosis and monitoring of Ph+ ALL patients.

Objective: To evaluate the performance of the Xpert® BCR-ABL Ultra p190 assay compared with the routine laboratory method for detecting BCR::ABL1 p190 transcripts in clinical samples.

Methods: A cross-sectional study was performed comparing the Xpert® BCR-ABL Ultra p190 assay with the reference method (XGEN MIX p190 kit). Residual peripheral blood and bone marrow samples previously tested for BCR::ABL1 p190 were analyzed individually or in pools. Samples underwent lysis, RNA extraction, and quantification by the reference method, followed by analysis using the GeneXpert system.

Results: Twenty-six samples with low, medium, and high transcript expression levels were evaluated. Nine samples were excluded from concordance analysis because the GeneXpert system detected BCR::ABL1 p190 in samples previously negative by the routine method, suggesting higher analytical sensitivity. Among the remaining 17 samples, concordance was 100%, exceeding the predefined acceptance criterion (≥85%).

Conclusion: The Xpert® BCR-ABL Ultra p190 assay demonstrated excellent analytical performance, showing complete concordance with the reference method and potential higher sensitivity. Additionally, its simplified workflow and reduced turnaround time support implementation in routine laboratory practice for rapid diagnosis and monitoring of ALL patients.