Computer vision quantitation of erythrocyte shape abnormalities provides diagnostic, prognostic, and mechanistic insight.

Examination of red blood cell (RBC) morphology in peripheral blood smears can help diagnose hematologic diseases, even in resource-limited settings, but this analysis remains subjective and semiquantitative with low throughput. Prior attempts to develop automated tools have been hampered by their poor reproducibility and limited clinical validation. Here, we present a novel, open-source machine-learning approach (denoted as RBC-diff) to quantify abnormal RBCs in peripheral smear images and generate an RBC morphology differential. RBC-diff cell counts showed high accuracy for single-cell classification (mean AUC, 0.93) and quantitation across smears (mean R2, 0.76 compared with experts, interexperts R2, 0.75). RBC-diff counts were concordant with the clinical morphology grading for 300 000+ images and recovered the expected pathophysiologic signals in diverse clinical cohorts. Criteria using RBC-diff counts distinguished thrombotic thrombocytopenic purpura and hemolytic uremic syndrome from other thrombotic microangiopathies, providing greater specificity than clinical morphology grading (72% vs 41%; P < .001) while maintaining high sensitivity (94% to 100%). Elevated RBC-diff schistocyte counts were associated with increased 6-month all-cause mortality in a cohort of 58 950 inpatients (9.5% mortality for schist. >1%, vs 4.7% for schist; <0.5%; P < .001) after controlling for comorbidities, demographics, clinical morphology grading, and blood count indices. RBC-diff also enabled the estimation of single-cell volume-morphology distributions, providing insight into the influence of morphology on routine blood count measures. Our codebase and expert-annotated images are included here to spur further advancement. These results illustrate that computer vision can enable rapid and accurate quantitation of RBC morphology, which may provide value in both clinical and research contexts.

Turning the spotlight on bone marrow adipocytes in haematological malignancy and non-malignant conditions.

Whilst bone marrow adipocytes (BMAd) have long been appreciated by clinical haemato-pathologists, it is only relatively recently, in the face of emerging data, that the adipocytic niche has come under the watchful eye of biologists. There is now mounting evidence to suggest that BMAds are not just a simple structural entity of bone marrow microenvironments but a bona fide driver of physio- and pathophysiological processes relevant to multiple aspects of health and disease. Whilst the truly multifaceted nature of BMAds has only just begun to emerge, paradigms have shifted already for normal, malignant and non-malignant haemopoiesis incorporating a view of adipocyte regulation. Major efforts are ongoing, to delineate the routes by which BMAds participate in health and disease with a final aim of achieving clinical tractability. This review summarises the emerging role of BMAds across the spectrum of normal and pathological haematological conditions with a particular focus on its impact on cancer therapy.

Histamine and Serotonin Levels in Bone Marrow Stem Cells Niche as Potential Biomarkers of Systemic Mastocytosis and Myeloproliferative Disorders.

Bone marrow studies currently provide a lot of valuable information in the diagnostics of hematological diseases including hematopoietic stem cells disorders. Our studies on low-molecular weight organic compounds in bone marrow stem cell niche in various pathogenic conditions, revealed relatively high variability of histamine levels in different groups of hematological diseases. It was also found that serotonin levels were significantly lower than those typically measured in peripheral blood as well as many have the influence on stem cells proliferative potential. This paper presents findings from quantitative and statistical analyses of histamine and serotonin levels. Bone marrow collected from patients undergoing routine diagnostic procedures for hematological diseases and receiving inpatient treatment were analyzed. Histamine and serotonin levels were measured using hydrophilic interaction liquid chromatography (HILIC) coupled with tandem mass spectrometry. Obtained data were analyzed statistically and correlated with the diagnosed groups of hematological diseases and the parameters of complete blood counts. Histamine was found in all tested samples, including those from patients without malignancy, and the reported levels were comparable to the reference values in blood. This observation allows us to assume that bone marrow cells can produce and accumulate histamine. Moreover, the statistical analysis revealed a significant relationship between histamine levels and diagnosed mastocytosis, and between histamine levels and myeloproliferative neoplasms. Different results were obtained for serotonin, and its concentrations in most cases were below the limit of quantification of the method used (< 0.2 ng/mL), which can only be compared to peripheral blood plasma. In a few cases, significantly higher serotonin levels were observed and it concerned diseases associated with an increased number of megakaryocytes in the bone marrow.

The hepatic extramedullary hematopoiesis during experimental murine Schistosomiasis mansoni.

Many years ago, our research group has demonstrated extramedullary hematopoiesis in the peripheral zone of murine hepatic schistosomal granulomas. In the present study, we revisit this phenomenon using new technical and conceptual approaches. Therefore, newborn mice were percutaneously infected by Schistosoma mansoni cercariae and euthanized between 35- and 60-days post infection. Liver samples were submitted to histopathology and immunohistochemical analyses. Cells under mitosis and/or expressing Ki67 demonstrated the proliferation of hematopoietic cells both around the parasite's eggs trapped in the liver and around hepatic vessels. After 50 days post infection, proliferating cells at different levels on differentiation were located preferentially in the peripheral zone of the granulomas, around the vessels and inside the sinusoids. The presence of acidic and sulfated glycoconjugates, reticular fibers and the absence of fibronectin characterized the microenvironment for attraction and maintenance of hematopoiesis. Some neutrophils secreted MMP9 from the earliest points of infection, indicating degradation of the extracellular matrix in regions of histolysis and a possible chemoattraction of hematopoietic stem cells to the liver. Fall-3+ cells and Sca-1+ cells indicated that early hematopoietic progenitors could be mobilized to the liver. Groups of vWF+ megakaryocytes suggest chemoattraction of these cells and/or migration, proliferation, and differentiation of very immature progenitors to this organ. The increase of blood vessels and extramedullary hematopoiesis in this environment, where markers of immature hematopoietic and endothelial cells have been identified, points to the possibility of the presence of progenitors for endothelial and hematopoietic cells in the liver during the infection. There is also the possibility of concomitant migration of more differentiated hematopoietic progenitors, that proliferate and differentiate in the liver, and the occurrence of angiogenesis caused by inflammation or release of ovular antigens that stimulate the activation and proliferation of endothelial cells. Altogether, these data increase knowledge about a murine model that is of interest for investigating the pathology of the schistosomiasis and also the dynamics of hematopoiesis.

Investigation of genetic and phenotypic heterogeneity in 37 Turkish patients with Kabuki and Kabuki-like phenotype.

Kabuki syndrome (KS) is a rare disorder characterized by distinct face, persistent fingertip pads, and intellectual disability (ID) caused by mutation in KMT2D (56%-76%) or KDM6A (5%-8%). Thirty-seven children aged 1-16 years who followed for median of 6.8 years were included in this study, which aimed to investigate the genetic and clinical characteristics of KS patients. KMT2D and KDM6A were evaluated by sequencing and multiplex-ligation-dependent probe amplification in 32 patients. Twenty-one pathogenic variants in KMT2D, of which 17 were truncated and nine were novel, one frame-shift novel variant in KDM6A were identified. The molecular diagnosis rate was 68.7% (22/32). In the whole-exome sequencing analysis performed in the remaining patients, no pathogenic variant that could cause any disease was detected. All patients had ID; 43.2% were severe and moderate. We observed that facial features that became more prominent with age were enough for a possible diagnosis of KS in infancy. The frequencies of facial features, cardiac and renal anomalies, short stature, microcephaly, and epilepsy did not differ depending on whether they had truncating or nontruncating variants or were in variant-negative KS-like group. This study has expanded clinical features of the disease, as well as identified new variants in genes causing KS.

Sleep disturbance is a common feature of Kabuki syndrome.

Kabuki syndrome (KS) is a rare epigenetic disorder caused by heterozygous loss of function variants in either KMT2D (90%) or KDM6A (10%), both involved in regulation of histone methylation. While sleep disturbance in other Mendelian disorders of the epigenetic machinery has been reported, no study has been conducted on sleep in KS. This study assessed sleep in 59 participants with KS using a validated sleep questionnaire. Participants ranged in age from 4 to 43 years old with 86% of participants having a pathogenic variant in KMT2D. In addition, data on adaptive function, behavior, anxiety, and quality of life were collected using their respective questionnaires. Some form of sleep issue was present in 71% of participants, with night-waking, daytime sleepiness, and sleep onset delay being the most prevalent. Sleep dysfunction was positively correlated with maladaptive behaviors, anxiety levels, and decreasing quality of life. Sleep issues were not correlated with adaptive function. This study establishes sleep disturbance as a common feature of KS. Quantitative sleep measures may be a useful outcome measure for clinical trials in KS. Further, clinicians caring for those with KS should consider sleep dysfunction as an important feature that impacts overall health and well being in these patients.

Extramedullary haematopoiesis presenting as an adnexal mass in a patient with ß-thalassaemia.

Solid masses of the ovaries raise the suspicion of malignancy or metastasis and require histological diagnosis. Extramedullary haematopoesis (EMH) is a rare histological finding of a mass of the adnexa. The sonographic pattern of EMH has rarely been described in the literature. Transvaginal biopsy of EMH has not been reported in the literature. We present a case of adnexal EMH in a patient affected with ß-thalassaemia, and we performed a narrative review. Only in our case, the sonographic pattern was described, and a transvaginal ultrasound-guided core biopsy was used. Assessing patients' medical history and correlating it to the findings of diagnostic imaging is of paramount importance when evaluating patients with adnexal masses. The correct interpretation of sonographic images can avoid unnecessarily invasive procedures. A transvaginal biopsy could be a safe, easy and well-tolerated method to gain definite histological diagnosis in cases where a primary ovarian malignancy is not suspected.

Of drills and bones: Giovanni Ghedini and the origin of bone marrow biopsy.

Bone marrow (BM) studies are pivotal for the diagnosis of haematological disorders. Their introduction into clinical haematology dates back to the work of Giovanni Ghedini (1877-1959), an Italian physician who first conceived BM sampling in 1908. Ghedini's proposal stemmed from his clinical experience and from the scientific developments that characterised his epoch. By presenting selected passages of Ghedini's publications, this report considers the theoretical and historical bases of his work and analyses its practical implications for modern haematology.

KSHV/HHV8-mediated hematologic diseases.

Kaposi sarcoma (KS) herpesvirus (KSHV), also known as human herpesvirus 8, is the causal agent of KS but is also pathogenetically related to several lymphoproliferative disorders, including primary effusion lymphoma (PEL)/extracavitary (EC) PEL, KSHV-associated multicentric Castleman disease (MCD), KSHV+ diffuse large B-cell lymphoma, and germinotropic lymphoproliferative disorder. These different KSHV-associated diseases may co-occur and may have overlapping features. KSHV, similar to Epstein-Barr virus (EBV), is a lymphotropic gammaherpesvirus that is preferentially present in abnormal lymphoid proliferations occurring in immunecompromised individuals. Notably, both KSHV and EBV can infect and transform the same B cell, which is frequently seen in KSHV+ EBV+ PEL/EC-PEL. The mechanisms by which KSHV leads to lymphoproliferative disorders is thought to be related to the expression of a few transforming viral genes that can affect cellular proliferation and survival. There are critical differences between KSHV-MCD and PEL/EC-PEL, the 2 most common KSHV-associated lymphoid proliferations, including viral associations, patterns of viral gene expression, and cellular differentiation stage reflected by the phenotype and genotype of the infected abnormal B cells. Advances in treatment have improved outcomes, but mortality rates remain high. Our deepening understanding of KSHV biology, clinical features of KSHV-associated diseases, and newer clinical interventions should lead to improved and increasingly targeted therapeutic interventions.

MODOMICS: a database of RNA modification pathways. 2021 update.

The MODOMICS database has been, since 2006, a manually curated and centralized resource, storing and distributing comprehensive information about modified ribonucleosides. Originally, it only contained data on the chemical structures of modified ribonucleosides, their biosynthetic pathways, the location of modified residues in RNA sequences, and RNA-modifying enzymes. Over the years, prompted by the accumulation of new knowledge and new types of data, it has been updated with new information and functionalities. In this new release, we have created a catalog of RNA modifications linked to human diseases, e.g., due to mutations in genes encoding modification enzymes. MODOMICS has been linked extensively to RCSB Protein Data Bank, and sequences of experimentally determined RNA structures with modified residues have been added. This expansion was accompanied by including nucleotide 5'-monophosphate residues. We redesigned the web interface and upgraded the database backend. In addition, a search engine for chemically similar modified residues has been included that can be queried by SMILES codes or by drawing chemical molecules. Finally, previously available datasets of modified residues, biosynthetic pathways, and RNA-modifying enzymes have been updated. Overall, we provide users with a new, enhanced, and restyled tool for research on RNA modification. MODOMICS is available at https://iimcb.genesilico.pl/modomics/.

Merkel cell carcinoma in the setting of hematologic disease is associated with unique features and potential pitfalls.

Merkel cell carcinoma (MCC) is a rare but aggressive neuroendocrine carcinoma of the skin, often associated with polyomavirus and ultra-violet light exposure. Immunosuppression is associated with increased risk of development of MCC, including that associated with hematolymphoid disorders such as chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). We sought to determine whether MCC arising in patients with hematologic disorders showed unique features. Searching archived material at three institutions, we identified 13 patients with MCC and at least one hematologic malignancy and 41 patients with MCC with no reported hematologic malignancy. CLL/SLL was the most common hematologic disorder in this setting (9/13 cases). Clinical history, variation in morphologic appearance, unusual site distribution and concern for progression of underlying hematologic disease all contributed to potential diagnostic challenges. Overlapping marker expression between MCC and hematologic neoplasms created potential diagnostic pitfalls (e.g. CD138, Pax5, TdT, Bcl2, CD56, and CD117). In addition, we newly identify expression of CD5 and LEF-1 in a subset of MCC, including in patients with CLL/SLL. MCC in patients with hematologic malignancy were more common in men (92% versus 59%, p < 0.05) and showed an unusual site predilection to non-sun exposed sites (3/13 on the buttocks) with none presenting on the face or scalp. By contrast, face or scalp lesions were common in MCC without an associated hematologic malignancy (17/41, p < 0.05). Our findings reaffirm the need for skin surveillance in the setting of immune deficiency and for vigilance to identify unusual presentations of MCC in patients with or without hematologic disorders.

Highly accurate differentiation of bone marrow cell morphologies using deep neural networks on a large image data set.

Biomedical applications of deep learning algorithms rely on large expert annotated data sets. The classification of bone marrow (BM) cell cytomorphology, an important cornerstone of hematological diagnosis, is still done manually thousands of times every day because of a lack of data sets and trained models. We applied convolutional neural networks (CNNs) to a large data set of 171 374 microscopic cytological images taken from BM smears from 945 patients diagnosed with a variety of hematological diseases. The data set is the largest expert-annotated pool of BM cytology images available in the literature. It allows us to train high-quality classifiers of leukocyte cytomorphology that identify a wide range of diagnostically relevant cell species with high precision and recall. Our CNNs outcompete previous feature-based approaches and provide a proof-of-concept for the classification problem of single BM cells. This study is a step toward automated evaluation of BM cell morphology using state-of-the-art image-classification algorithms. The underlying data set represents an educational resource, as well as a reference for future artificial intelligence-based approaches to BM cytomorphology.

Induced Pluripotent Stem Cells as a Tool for Modeling Hematologic Disorders and as a Potential Source for Cell-Based Therapies.

The breakthrough in human induced pluripotent stem cells (hiPSCs) has revolutionized the field of biomedical and pharmaceutical research and opened up vast opportunities for drug discovery and regenerative medicine, especially when combined with gene-editing technology. Numerous healthy and patient-derived hiPSCs for human disease modeling have been established, enabling mechanistic studies of pathogenesis, platforms for preclinical drug screening, and the development of novel therapeutic targets/approaches. Additionally, hiPSCs hold great promise for cell-based therapy, serving as an attractive cell source for generating stem/progenitor cells or functional differentiated cells for degenerative diseases, due to their unlimited proliferative capacity, pluripotency, and ethical acceptability. In this review, we provide an overview of hiPSCs and their utility in the study of hematologic disorders through hematopoietic differentiation. We highlight recent hereditary and acquired genetic hematologic disease modeling with patient-specific iPSCs, and discuss their applications as instrumental drug screening tools. The clinical applications of hiPSCs in cell-based therapy, including the next-generation cancer immunotherapy, are provided. Lastly, we discuss the current challenges that need to be addressed to fulfill the validity of hiPSC-based disease modeling and future perspectives of hiPSCs in the field of hematology.

[Activity report of the Bone Marrow Transplant Department of the Mohammed VI University Hospital, Marrakech, Morocco, over the period 2012- 2018]. / Bilan d'activité de l'unité de greffe de moelle osseuse du Centre Hospitalier Universitaire Mohamed VI de Marrakech, Maroc: 2012-2018.

INTRODUCTION: hematopoietic stem cell transplantation (HSCT) is part of the cellular immunotherapy arsenal. It is used in the treatment of several malignant and non-malignant hematological conditions as well as other extra-hematological diseases. HSCT has been described since 1950 and introduced in Morocco since the 2000s. GSCH is still little used in our context due to several legal, financial and organizational barriers. The purpose of this study is to report the experience of the Bone Marrow Transplant Department of the Marrakech's Mohammed VI University Hospital with hematopoietic stem cell transplantation, is one of the Hospital Departments in developing countries. METHODS: we carried out a descriptive retrospective study over a period of 6 years. RESULTS: during the study period, sixty-six HSCT were performed. Multiple myeloma was the main indication for HSCT in our case series (30 patients with autografts). In our case series, mortality rate was around 20%, relapse rate was 23% while complications rate was 38%. Despite the challenges, our results were encouraging during the long follow-up period. CONCLUSION: efforts still need to be made to improve therapy results.

Elevating Twitter-Based Journal Club Discussions by Leveraging a Voice-Based Platform: #HemepathJC Meets Clubhouse.

PURPOSE OF REVIEW: Social media-based scientific journal clubs provide an opportunity to promote published literature to a broader audience and allow robust multi-disciplinary and inter-professional discussion. Hematopathology Journal Club (#HemepathJC) on Twitter has successfully conducted monthly sessions since November 2019, covering topics related to lymphoma and leukemia. RECENT FINDINGS: To enhance connectivity, multitasking, and productivity, we present our experience of leveraging the voice-based platform Clubhouse concurrent with Twitter. The Twitter and Clubhouse partnership for #hemepathJC holds the potential to increase dissemination of scientific knowledge and further promote journal club format discussion.

Low-affinity immunoglobulin gamma Fc region receptor III-B (FcγRIIIB, CD16B) deficiency in patients with blood and immune system disorders.

Low-affinity immunoglobulin gamma Fc region receptor III-B (FcγRIIIB) deficiency is present in ˜0·05% of the general population. Among our patients, FcγRIIIB deficiency was less frequent in those with immune-system disorders (one of 1815 patients, 0·05%) than in those with blood disorders (nine of 2147 patients, 0·42%, P = 0·023): mainly primary immune thrombocytopenia (4·34%), therapy related myeloid neoplasms (1·16%) and myelodysplastic syndrome with excess blasts (1·28%). Four of the nine (44·4%) patients with blood disorders were diagnosed with or quickly evolved to acute myeloid leukaemia (AML), suggesting that FcγRIIIB deficiency could be an adverse prognostic factor for progression to AML that should be confirmed in large multicentre studies.

Neuroimaging in Kabuki syndrome and another KMT2D-related disorder.

Recognition of distinct phenotypic features is an important component of genetic diagnosis. Although CHARGE syndrome, Kabuki syndrome, and a recently delineated KMT2D Ex 38/39 allelic disorder exhibit significant overlap, differences on neuroimaging may help distinguish these conditions and guide genetic testing and variant interpretation. We present an infant clinically diagnosed with CHARGE syndrome but subsequently found to have a de novo missense variant in exon 38 of KMT2D, the gene implicated in both Kabuki syndrome and a distinct KMT2D allelic disorder. We compare her brain and inner ear morphology to a retrospective cohort of 21 patients with classic Kabuki syndrome and to typical CHARGE syndrome findings described in the literature. Thirteen of the 21 Kabuki syndrome patients had temporal bone imaging (5/13 CT, 12/13 MRI) and/or brain MRI (12/13) which revealed findings distinct from both CHARGE syndrome and the KMT2D allelic disorder. Our findings further elucidate the spectrum of inner ear dysmorphology distinguishing Kabuki syndrome and the KMT2D allelic disorder from CHARGE syndrome, suggesting that these three disorders may be differentiated at least in part by their inner ear anomalies.

Complex Modes of Inheritance in Hereditary Red Blood Cell Disorders: A Case Series Study of 155 Patients.

Hereditary erythrocytes disorders include a large group of conditions with heterogeneous molecular bases and phenotypes. We analyzed here a case series of 155 consecutive patients with clinical suspicion of hereditary erythrocyte defects referred to the Medical Genetics Unit from 2018 to 2020. All of the cases followed a diagnostic workflow based on a targeted next-generation sequencing panel of 86 genes causative of hereditary red blood cell defects. We obtained an overall diagnostic yield of 84% of the tested patients. Monogenic inheritance was seen for 69% (107/155), and multi-locus inheritance for 15% (23/155). PIEZO1 and SPTA1 were the most mutated loci. Accordingly, 16/23 patients with multi-locus inheritance showed dual molecular diagnosis of dehydrated hereditary stomatocytosis/xerocytosis and hereditary spherocytosis. These dual inheritance cases were fully characterized and were clinically indistinguishable from patients with hereditary spherocytosis. Additionally, their ektacytometry curves highlighted alterations of dual inheritance patients compared to both dehydrated hereditary stomatocytosis and hereditary spherocytosis. Our findings expand the genotypic spectrum of red blood cell disorders and indicate that multi-locus inheritance should be considered for analysis and counseling of these patients. Of note, the genetic testing was crucial for diagnosis of patients with a complex mode of inheritance.