Red blood cell fragmentation before hematopoietic progenitor cell transplantation

Usefulness of particle image analyzer for evaluation of fragmented red cells

Quantitative determination of fragmented red cells (FRCs) in peripheral blood is useful in various clinical fields. We have previously reported an automatic detection method using a hematology analyzer essentially based on detection of small red cells. We then tried to use another instrument, the FPIA 2100, to reflect the characteristic morphology of red cells. As the circularity obtained by FPIA 2100 correlated with the FRC%, this type of instrument might be helpful to establish better automatic detection methods.

Usefulness of Sequential Automated Analysis of Fragmented Red Blood Cells for the Differential Diagnosis of Thrombotic Thrombocytopenic Purpura-Hemolytic Uremic Syndrome following Allogeneic Hematopoietic Cell Transplantation

Differentiating thrombotic thrombocytopenic purpura-hemolytic uremic syndrome (TTP-HUS) from other complications following allogeneic hematopoietic cell transplantation (HPCT) requires objective, reliable markers. To this purpose, we assessed the clinical usefulness of sequential quantified analysis of fragmented red blood cells (FRC) with the Sysmex XE-2100 automated hematology analyzer. The correlation between manual and automated counting was significant (r = 0.917; P < .0001). Of 25 cases, the peak FRC percentage (FRC%) exceeded 1.3% after allogeneic HPCT in 11 cases, and lactate dehydrogenase levels were elevated in 5 of these 11 cases. Two patients received diagnoses of TTP-HUS following allogeneic HPCT, and both had initial diagnoses of acute graft-versus-host disease. In both cases, the sharp increase in the FRC% to >3% simultaneously with clinical exacerbation was helpful for differentiating TTP-HUS following allogeneic HPCT from other complications. We conclude that FRC% data sequentially obtained by an automated count seem to be useful as an objective marker of TTP-HUS following allogeneic HPCT.