Sickle Eye Project: a cross-sectional, non-interventional study of the prevalence of visual impairment due to sickle cell retinopathy and maculopathy in the UK.

INTRODUCTION: Sickle cell disease (SCD) is one of the most common genetic disorders in the UK, with over 15 000 people affected. Proliferative sickle cell retinopathy (SCR) is a well-described complication of SCD and can result in significant sight loss, although the prevalence in the UK is not currently known. There are currently no national screening guidelines for SCR, with wide variations in the management of the condition across the UK. METHODS AND ANALYSIS: The Sickle Eye Project is an epidemiological, cross-sectional, non-interventional study to determine the prevalence of visual impairment due to SCR and/or maculopathy in the UK. Haematologists in at least 16 geographically dispersed hospitals in the UK linked to participating eye clinics will offer study participation to consecutive patients meeting the inclusion criteria attending the sickle cell clinic. The following study procedures will be performed: (a) best corrected visual acuity with habitual correction and pinhole, (b) dilated slit lamp biomicroscopy and funduscopy, (c) optical coherence tomography (OCT), (d) OCT angiography where available, (e) ultrawide fundus photography, (f) National Eye Institute Visual Function Questionnaire-25 and (g) acceptability of retinal screening questionnaire. The primary outcome is the proportion of people with SCD with visual impairment defined as logarithm of the minimum angle of resolution ≥0.3 in at least one eye. Secondary outcomes include the prevalence of each stage of SCR and presence of maculopathy by age and genotype; correlation of stage of SCR and maculopathy to severity of SCD; the impact of SCR and presence of maculopathy on vision-related quality of life; and the acceptability to patients of routine retinal imaging for SCR and maculopathy. ETHICS AND DISSEMINATION: Ethical approval was obtained from the South Central-Oxford A Research Ethics Committee (REC 23/SC/0363). Findings will be reported through academic journals in ophthalmology and haematology.

Efficiency and Health Economic Evaluations of BD OneFlow™ Flow Cytometry Reagents for Diagnosing Chronic Lymphoid Leukemia.

REASON FOR THE STUDY: To standardize the use of flow cytometry for classifying hematological malignancies and make the results reliable and reproducible across laboratories, the EuroFlow™ Consortium published a comprehensive specification of antibody-fluorochrome conjugates, standard protocols, and algorithms for analysis. The BD OneFlow™ system builds on, and further standardizes, the EuroFlow protocols. We aimed to assess the effects on safety, efficiency, and costs for laboratories of adopting the BD OneFlow reagent tubes (LST and B-CLPD T1) for diagnosing chronic lymphocytic leukemia. METHODS: We compared in-house laboratory processes and results with those using the LST and B-CLPD T1 reagent tubes with, and without, blood film morphology. Outcome measures included concordance in classification results, and efficiency within the laboratory, that is, resource usage, staff time, unwanted events, and cost-consequences. RESULTS: There was 100% concordance between the classifications made with in-house flow cytometry and those with the BD OneFlow reagent tubes. Using BD OneFlow tubes required 13 hours less staff time per month (i.e. for 100 samples) than the in-house process. Sensitivity analyses explored the effects of uncertainties in the price of the BD OneFlow tubes and the prevalence of CLL and identified the thresholds at which laboratories might expect cost-savings from adopting the BD OneFlow system. Laboratory and clinical staff considered the BD OneFlow system to be safe and effective. CONCLUSIONS: Laboratories adopting the BD OneFlow system for classifying patients with suspected CLL can expect safe, efficient processes that can be cost saving if the discount on the list price, and prevalence of CLL (which will both vary between sites and countries), is within the thresholds suggested by the health economics sensitivity analysis. © 2019 International Clinical Cytometry Society.

An Intelligent Decision Support System for Leukaemia Diagnosis using Microscopic Blood Images.

This research proposes an intelligent decision support system for acute lymphoblastic leukaemia diagnosis from microscopic blood images. A novel clustering algorithm with stimulating discriminant measures (SDM) of both within- and between-cluster scatter variances is proposed to produce robust segmentation of nucleus and cytoplasm of lymphocytes/lymphoblasts. Specifically, the proposed between-cluster evaluation is formulated based on the trade-off of several between-cluster measures of well-known feature extraction methods. The SDM measures are used in conjuction with Genetic Algorithm for clustering nucleus, cytoplasm, and background regions. Subsequently, a total of eighty features consisting of shape, texture, and colour information of the nucleus and cytoplasm sub-images are extracted. A number of classifiers (multi-layer perceptron, Support Vector Machine (SVM) and Dempster-Shafer ensemble) are employed for lymphocyte/lymphoblast classification. Evaluated with the ALL-IDB2 database, the proposed SDM-based clustering overcomes the shortcomings of Fuzzy C-means which focuses purely on within-cluster scatter variance. It also outperforms Linear Discriminant Analysis and Fuzzy Compactness and Separation for nucleus-cytoplasm separation. The overall system achieves superior recognition rates of 96.72% and 96.67% accuracies using bootstrapping and 10-fold cross validation with Dempster-Shafer and SVM, respectively. The results also compare favourably with those reported in the literature, indicating the usefulness of the proposed SDM-based clustering method.

Phosphorylation of the leukemic oncoprotein EVI1 on serine 196 modulates DNA binding, transcriptional repression and transforming ability.

The EVI1 (ecotropic viral integration site 1) gene at 3q26 codes for a transcriptional regulator with an essential role in haematopoiesis. Overexpression of EVI1 in acute myeloid leukaemia (AML) is frequently associated with 3q26 rearrangements and confers extremely poor prognosis. EVI1 mediates transcriptional regulation, signalling, and epigenetic modifications by interacting with DNA, proteins and protein complexes. To explore to what extent protein phosphorylation impacts on EVI1 functions, we analysed endogenous EVI1 protein from a high EVI1 expressing Fanconi anaemia (FA) derived AML cell line. Mass spectrometric analysis of immunoprecipitated EVI1 revealed phosphorylation at serine 196 (S196) in the sixth zinc finger of the N-terminal zinc finger domain. Mutated EVI1 with an aspartate substitution at serine 196 (S196D), which mimics serine phosphorylation of this site, exhibited reduced DNA-binding and transcriptional repression from a gene promotor selectively targeted by the N-terminal zinc finger domain. Forced expression of the S196D mutant significantly reduced EVI1 mediated transformation of Rat1 fibroblasts. While EVI1-mediated serial replating of murine haematopoietic progenitors was maintained by EVI1-S196D, this was associated with significantly higher Evi1-trancript levels compared with WT-EVI1 or EVI1-S196A, mimicking S196 non-phosphorylated EVI1. These data suggest that EVI1 function is modulated by phosphorylation of the first zinc finger domain.

The histone demethylase KDM1A sustains the oncogenic potential of MLL-AF9 leukemia stem cells.

Using a mouse model of human MLL-AF9 leukemia, we identified the lysine-specific demethylase KDM1A (LSD1 or AOF2) as an essential regulator of leukemia stem cell (LSC) potential. KDM1A acts at genomic loci bound by MLL-AF9 to sustain expression of the associated oncogenic program, thus preventing differentiation and apoptosis. In vitro and in vivo pharmacologic targeting of KDM1A using tranylcypromine analogs active in the nanomolar range phenocopied Kdm1a knockdown in both murine and primary human AML cells exhibiting MLL translocations. By contrast, the clonogenic and repopulating potential of normal hematopoietic stem and progenitor cells was spared. Our data establish KDM1A as a key effector of the differentiation block in MLL leukemia, which may be selectively targeted to therapeutic effect.

Lactic acidosis expediting a diagnosis of acute lymphoblastic leukaemia.

We report the finding of a low venous bicarbonate and lactic acidosis in a patient with mild pancytopenia which raised the suspicion of haematological malignancy and expedited the diagnosis of acute lymphoblastic leukaemia. This report highlights the value of testing for lactic acidosis when haematological malignancies are considered and reviews the metabolism of lactic acidosis.

Treosulfan-containing regimens achieve high rates of engraftment associated with low transplant morbidity and mortality in children with non-malignant disease and significant co-morbidities.

Treosulfan is an immuno-suppressive and myeloablative alkylating agent that has been introduced as a conditioning agent in stem cell transplantation (SCT). Most studies have been performed in adult patients with malignancy where a low incidence of regimen-related toxicity has been reported. We report the use of treosulfan in 32 consecutive children undergoing SCT for non-malignant disease. Patients received a total treosulfan dose of 36 or 42 g/m(2)/patient given in three daily, divided doses. A range of other conditioning agents and serotherapy was administered to patients who underwent family donor SCT (n = 11), or unrelated donor SCT (n = 21). One patient (3%) died early. Transplant morbidity was limited and mucositis was only mild. Dermatological toxicity was frequent but mild. Twenty-eight patients (87.5%) established donor cell engraftment. In 25 patients (78%) there was adequate, stable donor engraftment. Four patients have required additional transplant procedures to maintain adequate donor-derived haemopoiesis. Twenty-seven patients (84%) survive with a median follow up of 417 d. There were four late deaths due to progression of the underlying disease, graft-versus-host disease or infection. Treosulfan-based conditioning regimens achieve excellent engraftment with reduced regimen-related toxicity in children with non-malignant disease at high risk for both regimen-related toxicity and graft failure.