The diagnostic use of ADVIA 2120i Siemens and an "APL criteria" can help to reduce the rate of early death in the APL.

Introduction: Acute promyelocytic leukemia (APL) is a type of acute myeloid leukemia (AML) with a life-threatening coagulopathy. Once it is suspected, ATRA should be started. Appreciation of APL details is critical, but an experienced hematopathologist may not be available. We developed an algorithm, based on the parameters generated by automated blood cell counter ADVIA 2120i Siemens that can aid the diagnosis of APL.

Methods: All parameters in the algorithm were selected on the bases of the pathophysiology of the APL and the analyzer's technology. We used c1 cutoff: PLT < 150 × 10 ; % Mono<10; % LUC<4; % hyperchromic cells > 2; %saturated cells ≥ 1; % blasts > 4. Satisfying at least five of six cutoffs, we obtained an "APL criteria". It was tested on 247.209 raw-data from routine and emergency samples and on 124 raw-data from APL. We performed a multiparametric analyses and obtained definitive cutoffs (c2). It was validated on a new group of 51.002 raw-data from routine and emergency. Finally, it was tested on AML and ALL, MDS, MPN, oncologic samples, and hemolytic and megaloblastic anemia.

Results: The algorithm provided a high sensitivity (86.30%) and high specificity (99.83%) in APL with high or normal number of WBC and satisfactory results in APL with cytopenia (80%). The specificity was very high also in groups of hematological and nonhematological diseases. It can be used as an "APL criteria" to alert pathologists of the possible presence of APL. It together with instrumental and classical morphology may allow to reduce the time of diagnosis with further reduction in early death.