Digital morphology in hematology diagnosis and education: The experience of the European LeukemiaNet WP10.

Hematological diagnostics is based on increasingly precise techniques of cellular and molecular analysis. The correct interpretation of the blood and bone marrow smears observed under an optical microscope still represents a cornerstone. Precise quantitative and qualitative cytomorphological criteria have recently been codified by up-to-date guidelines for diagnosing hematopoietic neoplasms. Morphological analysis has found formidable support in digital reproduction techniques, which have simplified the circulation of images for educational or consultation purposes. From 2007 to 2019, the Working Group WP10 of European LeukemiaNet (ELN) used, in annual exercises, digital images to support training in cytomorphology and verify harmonization and comparability in the interpretation of blood and bone marrow smears. We describe the design, development, and results of this program, which had 741 participants in-person or remotely, to which 2055 questions were submitted regarding the interpretation of cytomorphological images. We initially used circulation and presentation of digital microphotographs and then introduced a virtual microscopy (VM). Virtual slides were obtained using a whole slide imaging technique, similar to the one largely used in histopathology, to produce digitized scans of consecutive microscopic fields and reassembles them to obtain a complete virtual smear by stitching. Participants were required to identify cells in labeled fields of view of the virtual slides to obtain a morphological diagnosis. This work has demonstrated substantial improvements in diagnostic accuracy and harmonization with the VM technique. Between-observer concordance increased from 62.5% to 83.0%. The integrity of the digitalized film image, which provides a general context for cell abnormalities, was the main factor for this outcome.

Allogeneic cord blood red blood cells: assessing cord blood unit fractionation and validation.

BACKGROUND: For neonates and preterm infants, in whom a transfusion dose is low, the use of red blood cells (RBC) from cord blood appears to be feasible. Standardisation of fractionation and identification and assessment of quality control parameters for such RBC are still lacking. MATERIALS AND METHODS: We describe the process used to obtain RBC from cord blood for transfusion purposes, including quality controls to evaluate fractionation performance and the effects of storage. The cord RBC, to which SAG-M was added, were sampled on the day of fractionation, and 7 and 14 days (end of storage) later in order to measure the complete blood count, biochemical parameters and residual white blood cells. We also assessed microbial contamination. RESULTS: Data relative to 279 cord blood units were evaluated. The median gestational age at collection was 40 weeks (interquartile range [IQR] 39.1-40.7) and the median volume was 90 mL (IQR 81-103). Units were subjected to automated fractionation with Compomat, and packed RBC were suspended in SAG-M solution. The median volume of the SAG-M-suspended units was 31 mL (IQR 24.0-38.1) and the median haematocrit was 54.2% (IQR 49.4-59.5). The median volume after leukoreduction was 22 mL (IQR 17-28), with the volume decrease being similar in units leukoreduced before (n=75) or after (n=204) storage. The haematocrit of leukoreduced units was higher than that of buffy coat-depleted units. Storage at 2-6 °C for 14 days was accompanied by an increase of potassium levels and percentage of haemolysis. Microbial cultures were positive for 2.9% of the collected units. DISCUSSION: Fractionation of whole cord blood can provide RBC concentrates with similar baseline characteristics as units from adults. The transfusion dose and quality of the units appear safe and suitable for clinical use in neonates, with a satisfactory haematocrit and residual white blood cell content, despite a very variable collection volume.

Umbilical cord blood: Current uses for transfusion and regenerative medicine.

The past 20 years of experience with umbilical cord blood transplantation have demonstrated that cord blood is effective in the treatment of a spectrum of diseases, including hematological malignancies, bone marrow failure, hemoglobinopathies, and inborn errors of metabolism. However, only a few number of umbilical cord blood units collected have a cell content adequate for an allogenic hematopoietic stem cell transplantation. In the meanwhile, there is an increasing interest in exploiting cord blood derivatives in different fields. In this review, we will summarize the most recent updates on clinical applications of umbilical cord blood platelet derivatives for regenerative medicine, and we will revise the literature concerning the use of umbilical cord blood for autologous or allogeneic transfusion purposes. The methodological aspect and the biological characteristics of these products also will be discussed.

Hematological performance of a last generation automated blood cell counter: The Mindray BC-6800 Plus.

INTRODUCTION: Hematology analyzers produce reliable, reproducible, precise, accurate results, as well as a premicroscopic characterization of abnormal samples. We have evaluated the clinical performance of a new blood cell counter, which has been temporarily made available to our hematology laboratory. METHODS: Over four months, we analyzed with the Mindray BC-6800 Plus more than 1000 samples with a high incidence of hematological abnormalities, using recommended ICSH and CLSI protocols. We have also assessed flagging efficiency for abnormal cells and scattergram cell distribution. RESULTS: From a quantitative point of view, our assessment has identified state-of-the-art level reproducibility, excellent linearity, stability over 48°C at 4°C for the conventional parameters, lack of carry-over (<0.2%), and comparability with the routine instruments. These features would make the instrument suitable for immediate and smooth introduction in the hematology laboratory. Flags for abnormal cells are efficient; flag for blast cells has high sensitivity and predictive value of negative results. Additional benefits are provided by a competent interpretation of cell distribution scattergrams in samples from patients with specific hematological disorders. CONCLUSION: We have demonstrated good analytical and useful diagnostic performance of this new instrument, including effective selection of abnormal samples for informed microscope morphological analysis.

Umbilical cord blood as a source for red-blood-cell transfusion in neonatology: a systematic review.

The prevention and treatment of anaemia in newborn patients made tremendous progress in the last decades. However, red-blood-cell (RBC) transfusions remain unavoidable in many neonates candidate to surgery and especially in preterm infants. In particular, anaemia occurring in neonates born at extremely low gestational age is actually severe and frequently requires transfusions. Several approaches have been explored to prevent or even to reduce the threshold and the frequency of RBC transfusions. Among these, umbilical cord blood (UCB) collection and processing to obtain RBC components for autologous or allogeneic transfusion have been extensively investigated. In this systematic review, we revised the literature concerning the use of UCB for either autologous or allogeneic transfusion purposes and we illustrated the rationale for a transfusion therapy tailored to extremely preterm neonates, based on RBC concentrates from allogeneic UCB donations.

Allogeneic umbilical cord blood red cell concentrates: an innovative blood product for transfusion therapy of preterm infants.

BACKGROUND: Preterm infants often receive blood transfusions early in life. In this setting, umbilical cord blood (UCB) might be safer than adult blood (A) with respect to infectious and immunologic threats. OBJECTIVES: To evaluate, as a first objective, the feasibility of fulfilling transfusion needs of preterm infants with allogeneic UCB red blood cell (RBC) concentrates and, as a secondary objective, to assess the safety of allogeneic cord blood transfusions. METHODS: At the Neonatal Intensive Care Unit and the UNICATT Cord Blood Bank of 'A. Gemelli' Hospital in Rome, a prospective study was carried out over a 1-year period, enrolling newborns with gestational age ≤30 weeks and/or birth weight ≤1,500 g requiring RBC transfusions within the first 28 days of life. At first transfusion, patients were assigned to receive UCB-RBCs or A-RBCs depending on the availability of ABO-Rh(D)-matched UCB-RBC units. The same regimen (UCB-RBC or A-RBC units) was thereafter maintained, unless ABO-Rh(D)-matched UCB-RBC units were not available. RESULTS: Overall, 23 UCB-RBC units were transfused to 9 patients; the requests for UCB-RBC units were met in 45% of patients at the first transfusion and in 78% at the subsequent transfusions. At a median follow-up of 57 days (range 6-219), no acute or delayed transfusion-related adverse events occurred. Hematocrit gain after transfusion and time intervals between transfusions were similar in the UCB-RBC and A-RBC group, as well. CONCLUSIONS: Transfusing allogeneic UCB-RBC units in preterm infants appears a feasible and safe approach, although the transfusion needs of our study population were not completely covered. More data are necessary to validate this novel transfusion practice.