Eupransor demetentiae gen. nov., sp. nov., a novel fructophilic lactic acid bacterium from bumble bees.

Strain LMG 33000T was isolated from a Bombus lapidarius gut sample. It shared the highest percentage 16S rRNA sequence identity, average amino acid identity, and amino acid identity of conserved genes with Convivina intestini LMG 28291T (95.86 %, 69.9 and 76.2 %, respectively), and the highest percentage OrthoANIu value with Fructobacillus fructosus DSM 20349T (71.4 %). Phylogenomic analyses by means of 107 or 120 conserved genes consistently revealed Convivina as nearest neighbour genus. The draft genome of strain LMG 33000T was 1.44 Mbp in size and had a DNA G+C content of 46.1 mol%. Genomic and physiological analyses revealed that strain LMG 33000T was a typical obligately fructophilic lactic acid bacterium that lacked the adhE and aldh genes and that did not produce ethanol during glucose or fructose metabolism. In contrast, Convivina species have the adhE and aldh genes in their genomes and produced ethanol from glucose and fructose metabolism, which is typical for heterofermentative lactic acid bacteria. Moreover, strain LMG 33000T exhibited catalase activity, an unusual characteristic among lactic acid bacteria, that is not shared with Convivina species. Given its position in the phylogenomic trees, and the difference in genomic percentage G+C content and in physiological and metabolic characteristics between strain LMG 33000T and Convivina species, we considered it most appropriate to classify strain LMG 33000T into a novel genus and species within the Lactobacillaceae family for which we propose the name Eupransor demetentiae gen. nov., sp. nov., with LMG 33000T (=CECT 30958T) as the type strain.

A comparative genomic analysis of Fructobacillus evanidus sp. nov. from bumble bees.

The increase in studies on bee microbiomes is prompted by concerns over global pollinator declines. Bumble bees host core and non-core microbiota which may contribute to increased lifetime fitness. The presence of Fructobacillus in the gut microbiomes of bumble bee workers, or the replacement of core symbionts with Fructobacillus bacteria, has been considered a marker of dysbiosis. A phylogenomic analysis and functional genomic characterization of the genomes of 21 Fructobacillus isolates from bumble bees demonstrated that they represented four species, i.e. Fructobacillus cardui, Fructobacillus fructosus, Fructobacillus tropaeoli, and the novel species Fructobacillus evanidus sp. nov. Our results confirmed and substantiated the presence of two phylogenetically and functionally distinct Fructobacillus species clades that differ in genome size, percentage G + C content, the number of coding DNA sequences and metabolic characteristics. Clade 1 and clade 2 species differed in amino acid and, to a lesser extent, in carbohydrate metabolism, with F. evanidus and F. tropaeoli genomes featuring a higher number of complete metabolic pathways. While Fructobacillus genomes encoded genes that allow adhesion, biofilm formation, antibacterial activity and detoxification, other bacteria isolated from the bumble bee gut appeared better equipped to co-exist with the bumble bee host. The isolation and identification of multiple Fructobacillus species from several bumble bee gut samples in the present study also argued against a specific partnership between Fructobacillus species and their bumble bee hosts.

Proposal of three novel insect-associated Commensalibacter species: Commensalibacter melissae sp. nov., Commensalibacter communis sp. nov. and Commensalibacter papalotli sp. nov.

A recent modification of the Note to Rule 25a of the International Code for Nomenclature of Bacteria is used a posteriori by the List Editors of the International Journal of Systematic and Evolutionary Microbiology to justify the refusal to validate species protologues published in supplementary material prior to this formal decision. Authors are therefore forced to ask permission to reuse published data for the valid publication of such names. In the present letter we re-publish the species protologues of Commensalibacter melissae sp. nov., Commensalibacter communis sp. nov. and Commensalibacter papalotli sp. nov.

Evaluating the clinical validity of genes related to hemostasis and thrombosis using the Clinical Genome Resource gene curation framework.

BACKGROUND: Inherited bleeding, thrombotic, and platelet disorders (BTPDs) are a heterogeneous set of diseases, many of which are very rare globally. Over the past 5 decades, the genetic basis of some of these disorders has been identified, and recently, high-throughput sequencing has become the primary means of identifying disease-causing genetic variants. OBJECTIVES: Knowledge of the clinical validity of a gene-disease relationship is essential to provide an accurate diagnosis based on results of diagnostic gene panel tests and inform the construction of such panels. The Scientific and Standardization Committee for Genetics in Thrombosis and Hemostasis undertook a curation process for selecting 96 TIER1 genes for BTPDs. The purpose of the process was to evaluate the evidence supporting each gene-disease relationship and provide an expert-reviewed classification for the clinical validity of genes associated with BTPDs. METHODS: The Clinical Genome Resource (ClinGen) Hemostasis/Thrombosis Gene Curation Expert Panel assessed the strength of evidence for TIER1 genes using the semiquantitative ClinGen gene-disease clinical validity framework. ClinGen Lumping and Splitting guidelines were used to determine the appropriate disease entity or entities for each gene, and 101 gene-disease relationships were identified for curation. RESULTS: The final outcome included 68 Definitive (67%), 26 Moderate (26%), and 7 Limited (7%) classifications. The summary of each curation is available on the ClinGen website. CONCLUSION: Expert-reviewed assignment of gene-disease relationships by the ClinGen Hemostasis/Thrombosis Gene Curation Expert Panel facilitates accurate molecular diagnoses of BTPDs by clinicians and diagnostic laboratories. These curation efforts can allow genetic testing to focus on genes with a validated role in disease.

Labor and delivery: DIC, HELLP, preeclampsia.

Hematologists are often needed to assist with the management of microangiopathic emergencies in pregnancy. A firm understanding of the diagnosis and management of preeclampsia with severe features, hemolysis elevated liver enzyme and low platelet syndrome, and disseminated intravascular coagulation, which are the most common causes of microangiopathic emergencies, is critical. However, being able to consider when other microangiopathic emergencies (acute fatty liver of pregnancy, congenital and acquired thrombotic thrombocytopenic purpura, complement mediated microangiopathy, antiphospholipid syndrome) should be considered is imperative. The hematologist and obstetric team should work together to optimize the care of common as well as rare hematologic emergencies.

More than just mild thrombocytopenia: Clinical clues in the diagnosis of germline predisposition to malignancy from a rare ETV6 variant.

Key Clinical Message: In the evaluation of patients with longstanding mild thrombocytopenia, emphasis on family history, genetic testing, and collaborative clinical and laboratory-based family studies can ensure proper diagnosis and monitoring for malignancies. Abstract: We report the diagnostic approach to mild and non-specific thrombocytopenia with unclear genetic findings in two sisters. Genetic sequencing revealed a rare variant in ETS Variant Transcription Factor 6, which is associated with inherited thrombocytopenia with predisposition to hematologic malignancy. Familial studies provided sufficient evidence for a likely pathogenic classification.

A phylogenomic and comparative genomic analysis of Commensalibacter, a versatile insect symbiont.

BACKGROUND: To understand mechanisms of adaptation and plasticity of pollinators and other insects a better understanding of diversity and function of their key symbionts is required. Commensalibacter is a genus of acetic acid bacterial symbionts in the gut of honey bees and other insect species, yet little information is available on the diversity and function of Commensalibacter bacteria. In the present study, whole-genome sequences of 12 Commensalibacter isolates from bumble bees, butterflies, Asian hornets and rowan berries were determined, and publicly available genome assemblies of 14 Commensalibacter strains were used in a phylogenomic and comparative genomic analysis. RESULTS: The phylogenomic analysis revealed that the 26 Commensalibacter isolates represented four species, i.e. Commensalibacter intestini and three novel species for which we propose the names Commensalibacter melissae sp. nov., Commensalibacter communis sp. nov. and Commensalibacter papalotli sp. nov. Comparative genomic analysis revealed that the four Commensalibacter species had similar genetic pathways for central metabolism characterized by a complete tricarboxylic acid cycle and pentose phosphate pathway, but their genomes differed in size, G + C content, amino acid metabolism and carbohydrate-utilizing enzymes. The reduced genome size, the large number of species-specific gene clusters, and the small number of gene clusters shared between C. melissae and other Commensalibacter species suggested a unique evolutionary process in C. melissae, the Western honey bee symbiont. CONCLUSION: The genus Commensalibacter is a widely distributed insect symbiont that consists of multiple species, each contributing in a species specific manner to the physiology of the holobiont host.

Peripartum management of deep venous thrombosis in the context of antithrombin deficiency and May-Thurner syndrome.

Literature regarding the management of thrombus refractory to first-line treatment in the setting of pregnancy is limited, and management is made even more complicated in the context of thrombophilia. This case reviews the management of a patient with antithrombin deficiency who developed a massive thrombus during pregnancy, which was complicated by May-Thurner syndrome, lack of improvement with heparin, and preterm labor. The patient received multidisciplinary care throughout the pregnancy. At 35 weeks, anticoagulation was paused as she underwent induction of labor and delivery followed by postpartum placement of inferior vena cava filter and restarting heparin. Successful management of our pregnant patient with thrombus refractory to heparin hinged on individualized treatment for medical optimization with anticoagulation and antithrombin concentrate prior to labor followed by immediate postpartum placement of inferior vena cava filter.

ANKRD26-Related Thrombocytopenia and Predisposition to Myeloid Neoplasms.

PURPOSE OF REVIEW: This review describes ANKRD26-related thrombocytopenia (RT) from a molecular, clinical, and laboratory perspective, with a focus on the clinical decision-making that takes place in the diagnosis and management of families with ANKRD26-RT. RECENT FINDINGS: ANKRD26-related thrombocytopenia (ANKRD26-RT) is a non-syndromic autosomal dominant thrombocytopenia with predisposition to hematologic neoplasm. The clinical presentation is variable with moderate thrombocytopenia with normal platelet size and absent to mild bleeding being the hallmark which makes it difficult to distinguish from other inherited thrombocytopenias. The pathophysiology involves overexpression of ANKRD26 through loss of inhibitory control by transcription factors RUNX1 and FLI1. The great majority of disease-causing variants are in the 5' untranslated region. Acute myeloid leukemia, myelodysplastic syndrome, and chronic myelomonocytic leukemia have been reported to occur in the context of germline variants in ANKRD26, with the development of somatic driver mutations in hematopoietic regulators playing an important role in malignant transformation. In the absence of clear risk estimates of development of malignancy, optimal surveillance strategies and interventions to reduce risk of evolution to a myeloid disorder, multidisciplinary evaluation, with a strong genetic counseling framework is essential in the approach to these patients and their families. Gene-specific expertise and a multidisciplinary approach are important in the diagnosis and treatment of patients and families with ANKRD26-RT. These strategies help overcome the challenges faced by clinicians in the evaluation of individuals with a rare, non-syndromic, inherited disorder with predisposition to hematologic malignancy for which large data to guide decision-making is not available.

Rational Design and Experimental Analysis of Short-Oligonucleotide Substrate Specificity for Targeting Bacterial Nucleases.

An undecamer oligonucleotide probe based on a pair of deoxythymidines flanked by several modified nucleotides is a specific and highly efficient biosensor for micrococcal nuclease (MNase), an endonuclease produced by Staphylococcus aureus. Herein, the interaction mode and cleavage process on such oligonucleotide probes are identified and described for the first time. Also, we designed truncated pentamer probes as the minimum-length substrates required for specific and efficient biosensing. By means of computational (virtual docking) and experimental (ultra-performance liquid chromatography-mass spectrometry and matrix-assisted laser desorption ionization time-of-flight) techniques, we perform a sequence/structure-activity relationship analysis, propose a catalytically active substrate-enzyme complex, and elucidate a novel two-step phosphodiester bond hydrolysis mechanism, identifying the cleavage sites and detecting and quantifying the resulting probe fragments. Our results unravel a picture of both the enzyme-biosensor complex and a two-step cleavage/biosensing mechanism, key to the rational oligonucleotide design process.

Diagnostic approach to the patient with a suspected inherited platelet disorder: Who and how to test.

Bleeding and thrombocytopenia are common referrals to the pediatric and adult hematology practice. The differential diagnosis encompasses a wide spectrum of entities that vary in acuity, severity, and etiology. Most will be acquired (especially in adult patients), but many can be inherited, and some may have manifestations affecting other organ systems. The first step: defining whether the symptoms and/or laboratory findings are clinically significant and warrant additional work-up, can be equally as challenging as reaching the diagnosis itself. How much bleeding is too much to be considered normal? How low of a platelet count is too low? Once the decision has been made to pursue additional studies, considering the increasing number of laboratory tests available, the diagnostic process can be complex. In this article, we outline a general approach for the evaluation of patients in whom an inherited platelet disorder is being considered. We present two clinical vignettes as introduction to the diagnostic approach to inherited platelet disorders. We describe the rationale for the different types of tests that are clinically available, their limitations, and finally the challenges that are frequently encountered in the interpretation of results. We also intend to provide some guidance on the expected phenotype in terms of severity of bleeding and/or thrombocytopenia according to the etiology of the inherited disorder. Our goal is to provide the practicing hematologist with a practical framework that is clinically applicable in their daily practice.

GoldVariants, a resource for sharing rare genetic variants detected in bleeding, thrombotic, and platelet disorders: Communication from the ISTH SSC Subcommittee on Genomics in Thrombosis and Hemostasis.

The implementation of high-throughput sequencing (HTS) technologies in research and diagnostic laboratories has linked many new genes to rare bleeding, thrombotic, and platelet disorders (BTPD), and revealed multiple genetic variants linked to those disorders, many of them being of uncertain pathogenicity when considering the accepted evidence (variant consequence, frequency in control datasets, number of reported patients, prediction models, and functional assays). The sequencing effort has also resulted in resources for gathering disease-causing variants associated with specific genes, but for BTPD, such well-curated databases exist only for a few genes. On the other hand, submissions by individuals or diagnostic laboratories to the variant database ClinVar are hampered by the lack of a submission process tailored to capture the specific features of hemostatic diseases. As we move toward the implementation of HTS in the diagnosis of BTPD, the Scientific and Standardization Committee for Genetics in Thrombosis and Haemostasis has developed and tested a REDCap-based interface, aimed at the community, to submit curated genetic variants for diagnostic-grade BTPD genes. Here, we describe the use of the interface and the initial submission of 821 variants from 30 different centers covering 14 countries. This open-access variant resource will be shared with the community to improve variant classification and regular bulk data transfer to ClinVar.

Severe thrombocytopenia and microangiopathic hemolytic anemia in pregnancy: A guide for the consulting hematologist.

A hematologist receives a call from a maternal-fetal medicine (MFM) physician about a previously healthy patient who became ill at 25 weeks' gestation. Her mental status is deteriorating. There are signs of fetal distress. Platelet count and hemoglobin are falling. The MFM physician is considering the hemolysis, elevated liver enzymes and low platelet count (HELLP) syndrome. For the hematologist, everything seems unfamiliar. Our goal is to provide hematologists with the fundamental knowledge required for understanding and managing these patients who become suddenly and seriously ill during pregnancy and in whom thrombocytopenia and microangiopathic hemolytic anemia are part of their presentation.

Recognition of the unique bleeding pattern and laboratory findings in acquired haemophilia A facilitates prompt treatment of a life-threatening disorder.

Acquired haemophilia A (AHA) is an uncommon but severe acquired bleeding disorder caused by the development of antibodies against clotting factor VIII, impairing secondary haemostasis. It is more common in older individuals and characteristically presents with spontaneous soft tissue bleeding that can rapidly become life-threatening. Definitive treatment requires immunosuppression to eradicate anti-FVIII antibodies, while providing haemostatic support to manage bleeding. Transfusions of fresh frozen plasma or cryoprecipitate, typically used to treat severe bleeding, are ineffective in patients with AHA. Instead, highly specialised clotting factor concentrates are required. While the appearance and extent of the soft tissue bleeding and the markedly prolonged activated partial thromboplastin time are characteristic, lack of familiarity with this disease process can lead to significant treatment delays. We report the clinical course and management of a 65-year-old woman who presented with severe anaemia of unclear aetiology with unrecognised soft tissue bleeding who was subsequently diagnosed with AHA.

The Society for Obstetric Anesthesia and Perinatology Interdisciplinary Consensus Statement on Neuraxial Procedures in Obstetric Patients With Thrombocytopenia.

Because up to 12% of obstetric patients meet criteria for the diagnosis of thrombocytopenia in pregnancy, it is not infrequent that the anesthesiologist must decide whether to proceed with a neuraxial procedure in an affected patient. Given the potential morbidity associated with general anesthesia for cesarean delivery, thoughtful consideration of which patients with thrombocytopenia are likely to have an increased risk of spinal epidural hematoma with neuraxial procedures, and when these risks outweigh the relative benefits is important to consider and to inform shared decision making with patients. Because there are substantial risks associated with withholding a neuraxial analgesic/anesthetic procedure in obstetric patients, every effort should be made to perform a bleeding history assessment and determine the thrombocytopenia etiology before admission for delivery. Whereas multiple other professional societies (obstetric, interventional pain, and hematologic) have published guidelines addressing platelet thresholds for safe neuraxial procedures, the US anesthesia professional societies have been silent on this topic. Despite a paucity of high-quality data, there are now meta-analyses that provide better estimations of risks. An interdisciplinary taskforce was convened to unite the relevant professional societies, synthesize the data, and provide a practical decision algorithm to help inform risk-benefit discussions and shared decision making with patients. Through a systematic review and modified Delphi process, the taskforce concluded that the best available evidence indicates the risk of spinal epidural hematoma associated with a platelet count ≥70,000 × 106/L is likely to be very low in obstetric patients with thrombocytopenia secondary to gestational thrombocytopenia, immune thrombocytopenia (ITP), and hypertensive disorders of pregnancy in the absence of other risk factors. Ultimately, the decision of whether to proceed with a neuraxial procedure in an obstetric patient with thrombocytopenia occurs within a clinical context. Potentially relevant factors include, but are not limited to, patient comorbidities, obstetric risk factors, airway examination, available airway equipment, risk of general anesthesia, and patient preference.

Gray Platelet Syndrome Presenting With Pancytopenia, Splenomegaly, and Bone Marrow Fibrosis.

OBJECTIVES: Gray platelet syndrome (GPS) is a rare platelet storage pool disorder associated with a marked decrease or absence of platelet α-granules and their contents. It is characterized clinically by mild to moderate bleeding; moderate macrothrombocytopenia with large, agranular platelets; splenomegaly; and bone marrow fibrosis. Electron microscopy confirms markedly reduced or absent α-granules in platelets and megakaryocytes. The classic description of GPS is caused by homozygous mutations in NBEAL2 (neurobeachinlike 2). METHODS: A 28-year-old Hispanic man with a history of easy bruising and occasional episodes of epistaxis sought treatment for pancytopenia and splenomegaly. Peripheral blood smear and bone marrow analysis, electron microscopy, and next-generation sequencing were performed. RESULTS: Large and agranular platelets were present in the peripheral blood. There was bone marrow fibrosis. Electron microscopy of the platelets showed absence of α-granules. Next-generation sequencing revealed a germline apparently homozygous nonsense variant in the NBEAL2 gene: c.5674C>T, p.Gln1892X (p.Q1829X). CONCLUSIONS: The differential diagnosis of GPS includes a myeloid neoplasm such as myelodysplastic syndrome with bone marrow fibrosis. The availability of diagnostic genetic panels for hereditable platelet disorders can assist in the recognition of GPS and other platelet disorders. We also describe a previously unreported pathogenic germline homozygous nonsense variant in the NBEAL2 gene: c.5674C>T, p.Gln1892X (p.Q1829X) in a patient with GPS.

Specifications of the variant curation guidelines for ITGA2B/ITGB3: ClinGen Platelet Disorder Variant Curation Panel.

Accurate and consistent sequence variant interpretation is critical to the correct diagnosis and appropriate clinical management and counseling of patients with inherited genetic disorders. To minimize discrepancies in variant curation and classification among different clinical laboratories, the American College of Medical Genetics and Genomics (ACMG), along with the Association for Molecular Pathology (AMP), published standards and guidelines for the interpretation of sequence variants in 2015. Because the rules are not universally applicable to different genes or disorders, the Clinical Genome Resource (ClinGen) Platelet Disorder Expert Panel (PD-EP) has been tasked to make ACMG/AMP rule specifications for inherited platelet disorders. ITGA2B and ITGB3, the genes underlying autosomal recessive Glanzmann thrombasthenia (GT), were selected as the pilot genes for specification. Eight types of evidence covering clinical phenotype, functional data, and computational/population data were evaluated in the context of GT by the ClinGen PD-EP. The preliminary specifications were validated with 70 pilot ITGA2B/ITGB3 variants and further refined. In the final adapted criteria, gene- or disease-based specifications were made to 16 rules, including 7 with adjustable strength; no modification was made to 5 rules; and 7 rules were deemed not applicable to GT. Employing the GT-specific ACMG/AMP criteria to the pilot variants resulted in a reduction of variants classified with unknown significance from 29% to 20%. The overall concordance with the initial expert assertions was 71%. These adapted criteria will serve as guidelines for GT-related variant interpretation to increase specificity and consistency across laboratories and allow for better clinical integration of genetic knowledge into patient care.