Use of Neutrophil Cell Population Data for the Detection of Neutrophil Hypergranulation and Other Neutrophil Inclusions As Dohle Bodies, Cytoplasm Vacuolation

Abstract Neutrophil hypergranulation, Dohle Bodies and Neutrophil vacuolation (Neutrophil Toxic Changes) are morphological cell changes seen in a number of clinically significant situations e.g. Bacterial Infection, Myelodysplastic Syndromes, etc. With increased automation, auto validation and reduced blood film review rates within Haematology, clinically important Neutrophil morphological changes may be missed, with potential delay in patient management / treatment. The detection/flagging of Neutrophil degranulation using Cell Population Data has been previously published (Laboratory Haematology 13:98-102, 2007), but there are no published DxH references for the detection / flagging of Neutrophil Toxic Changes, especially using the new CPD data from DxH 800. Cell Population Data (CPD) - numerical data developed through VCS technology (Volume, Conductivity, Scatter Laser (Light scattering) 3D cube on DxH800 & LH700 series instruments, gives additional information about the leukocytes analysed. This data is available as part of the Research cell population Data, around 8200 leukocyte events are anlaysed and the information reported as the Mean and SD of each leukocyte population. Additionally the DxH 800 uses five angles of Laser Light Scatter called: AL2, MALS, LMALS, UMALS and LALS. Study: We have identified 89 consecutive routine cases with Neutrophil Toxic Changes (NTC) and compared our data with normal cases (31). This information was analysed to identify the Neutrophil CPD that permit the detection of Neutrophil toxic changes. This discriminant CPD function was subsequently used to re-evaluate the same 89 samples with NTC, from a pool of samples from a routine lab (149 normal samples and 555 pooled abnormal samples) to determine the efficiency of the parameters found. Analysis of this data identified that the best parameter was the Neutrophil Standard Deviation of Axial Light Loss (SD-AL2-NE ): Abstract 4966. Table ROC analysis of 89 cases with NTC compared with 31 normal casesMean NormalMean NE Toxic ChangesStudent T-test pAUCSENSSPECIFCUT-OFF Sign.ROCn3189SD-AL2-NE8.874213.9263p < 0.00010.98692.1100>10.31 p < 0.0001MN-LMALS-NE139.2903122.5843p < 0.00010.90983.190.3<133 p < 0.0001SD-LMALS-NE11.57115.1412p < 0.00010.88871.996.8>12.79 p < 0.0001SD-MALS-NE9.19911.3715p < 0.00010.88580.993.5>9.75 p < 0.0001SD-LALS-NE27.627738.85p = 0.12090.86580.996.8>28.57 p < 0.0001 Table ROC analysis of 89 cases with NTC compared with 704 pooled samples (149 normal 555 pooled abnormal) AUC SENS SPECIF CUT-OFF Sign.ROC SD-AL2-NE 0.94 95.5 86.4 >10.75 p < 0.0001 MN-LMALS-NE 0.89 85.4 85.2 <134.9 p < 0.0001 SD-LMALS-NE 0.844 84.3 73.8 >13.1 p < 0.0001 SD-MALS-NE 0.835 82 76.3 >10.51 p < 0.0001 SD-LALS-NE 0.83 79.8 80.3 >28.27 p < 0.0001 We believe that adding this decision rule to the DxH800 instrument workstation - IF SD-AL2-NE > >10.75 then “Suspect flag of Neutrophil Cytoplasmic Toxic Changes (Dohle, Hypergran, Vacuoles)” may help to detect cases with these neutrophil abnormalities. We suggest that First time presentations with this suspect flag should result in the examination of the blood smear review the presence of these cell abnormalities. Prospective studies are necessary to validate these preliminary results. Disclosures No relevant conflicts of interest to declare.