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Mechanical circulatory support (MCS) is the overarching term that encompasses the temporary and durable devices used in patients with severe heart failure. MCS disturbs the hematologic and coagulation system, leading to platelet activation, activation of the contact pathway of coagulation, and acquired von Willebrand syndrome. Ischemic stroke and major hemorrhage occur in up to 30% of patients. Hematologists are an essential part of the MCS team because they understand the delicate balance between bleeding and clotting and alteration of hemostasis with antithrombotic therapy. However, prior to this important collaborative role, learning the terminology used in the field and types of MCS devices allows improved communication with the MCS team and best patient care. Understanding which antithromobotic therapies are used at baseline is also required to provide recommendations if hemorrhage or thrombosis occurs. Additional challenging consultations in MCS patients include the influence of thrombophilia on the risk for thrombosis and management of heparin-induced thrombocytopenia. This narrative review will provide a foundation to understand MCS devices how to prevent, diagnose, and manage MCS thrombosis for the practicing hematologist.

Obstetrical hematology represents challenges not only for the patient, but also for her progeny. In particular, bleeding disorders, both congenital and acquired, not only present problems both for delivery and in the immediate postpartum period, but also may have significant implications for the fetus and neonate. Women with congenital bleeding disorders or who are carriers of X-linked or autosomal disorders should be counseled prior to conception so that pregnancy can be safely undertaken with careful preparation. A treatment plan should be set up by a specialized care team that includes the hematologist, obstetrician, and anesthesiologist; the patient should be followed closely during pregnancy, through delivery, and in the immediate postpartum period. Acquired disorders of hemostasis that occur with pregnancy may present particular diagnostic difficulties and require rapid diagnosis and management.

The increasing use of immunophenotypic and molecular analysis in the routine evaluation of patients with lymphocytosis, lymphadenopathy, or other hematologic disorders has led to the identification of unexpected small clonal lymphoid populations. These clones, sometimes with disease-specific markers, such as the t(14;18), are especially challenging for the clinician because of their unknown biologic potential and uncertain clinical behavior. Study of these early lymphoid lesions is providing important clues to the process of lymphomagenesis, and may provide the rationale for preemptive therapy in the future. More and more, the hematologist/oncologist is consulted regarding otherwise healthy individuals with lymphadenopathy and/or lymphocytosis, and pathology reports that confound the referring internist or surgeon. The report does not name a malignant lymphoproliferative disorder, but is not completely “normal”. Does the patient have a benign or malignant condition? How should they be evaluated? Is treatment indicated? These patients prove challenging for the consulting hematologist as well as the referring physician. In this review, we will focus on some of these scenarios and attempt to provide guidance for their management.

The current management of B-chronic lymphocytic leukemia (CLL) is no longer straightforward for the practicing hematologist. Rapid advances in diagnostic precision, methods of predicting prognosis, understanding of natural history of CLL, recognition of clinical complications, clarification of the quality of life (QOL) issues facing the CLL patient, and the exciting array of novel treatment approaches have made the care of the CLL patient more demanding. This review is focused on summarizing these advances in order to provide a framework for integrating this knowledge into routine hematologic practice.

Improvements in anticancer treatments, the ability to modify myelosuppression profiles, greater duration and intensity of immunosuppression, and the variety of available antimicrobial therapies have influenced the spectrum of pathogens associated with invasive fungal infection complicating treatment of hematological malignancies and hematopoietic stem cell transplantation. The approaches to the management of these infections encompass strategies of prevention for all those at risk, pre-emptive therapy based upon surrogates of infection before the onset of clinical disease, empirical therapy for patients with clinical evidence of early disease, and directed or targeted therapy for infected patients with established disease. Chemoprophylaxis is effective if applied to the highest risk patients over the duration of the risk. Pre-emptive strategies, while promising, have yet to be validated and linked to reliably predictive nonmicrobiological diagnostic techniques. Empirical antifungal therapy, as it is currently applied, now seems questionable. Patients with probable or proven invasive fungal infection still have suboptimal outcomes despite the availability of promising anti-fungal agents. Strategies examining the concept of dose-intensity and combination regimens require careful study and cannot yet be regarded as an acceptable standard of practice.

Immune (or idiopathic) thrombocytopenic purpura (ITP) is commonly encountered by the practicing hematologist. Clinical management decisions have traditionally been guided by individual training and past experience. Input from the literature has been more from observational reports of case series than from scientific results of hypothesis-driven research. Practice guidelines and several surveys of clinical hematology practice have highlighted important questions in the field, and in the past 5 to 10 years both clinical and laboratory investigations have produced valuable new information. Thrombopoietin levels are normal or only slightly increased in ITP, and stimulation of thrombopoiesis appears to be a promising new therapeutic approach in clinical trials. Chronic, refractory ITP in children or adults remains a challenge for the hematologist. It is this group that has the greatest risk of serious bleeding, particularly among the elderly. The anti-B–cell monoclonal antibody, anti-CD20, has shown benefit in phase I/II clinical trials in patients who had failed a number of previous therapeutic modalities. The standard for clinical research into therapy for ITP has become evidence-based medicine, and more prospective, randomized clinical trials are being completed by multi-institutional study groups.

Over 3 million people in the United Staes aged 65 years and older are anemic. This condition is associated with significant functional impairment and, perhaps, increased mortality. In March 2004, the American Society of Hematology (in conjunction with the National Institute of Aging) convened a “blue ribbon” panel of twenty physicians who are experts on various aspects of this topic. This paper highlights important consensus concepts resulting from that meeting. In particular, four areas of thought are shared. First, the epidemiology of anemia in the elderly is reviewed, including its definition, its expression in different racial groups, and its wide-ranging manifestations. Second, the pathophysiology of anemia in the elderly is reviewed as pertains to three general etiological categories (nutritional, chronic diseases, and so-called “unexplained” anemias). Particular emphasis is given to pathophysiologic mechanisms of anemia that are potentially unique to this age group. Third, a practical approach to the diagnosis and management of anemia for this patient population for the practicing hematologist is provided. Finally, the public health implications of anemia in the elderly for key stakeholder constituencies will be discussed in the oral presentation.

Clinical hematologists are faced with a growing list of new genetic-based tools for identifying a patient’s risk of disease. While many of the disease-specific tests are readily available, validation studies are required. Furthermore, genetic-based tests are being pushed to their technical limits, such as testing a single cell prior to embryo selection and transfer for couples at risk of genetic disease. As a result, misdiagnosis or misinterpretation of the data may result. As new genetic testing opportunities proliferate, the hematologist needs to be aware of the medical and legal issues surrounding their use. Furthermore, the hematologist needs to consider the psychological, ethical and social implications of this new field of genomic-based medicine.

The diagnosis and management of thrombocytopenia is a growing component in the practice of hematology. The frequency with which hematologists are called in consultation for thrombocytopenia continues to increase with the advent of routine automated platelet determinations and the introduction of new medications. For most patients, such as those with inherited and auto-immune thrombocytopenia, emphasis is focused on efforts to treat or forestall bleeding without excess drug-induced toxicity or burden to the patient. However, in disorders such as heparin-induced thrombocytopenia (HIT), avoidance of thrombotic complications is the key to management. In this chapter, we provide the pediatric and adult hematologist with new insights into the pathogenesis and recognition of congenital inherited thrombocytopenias (CTP), a hitherto difficult to comprehend constellation of clinical entities. We also highlight new approaches to the diagnosis and treatment of two of the more common thrombocytopenic conditions encountered in practice, autoimmune or idiopathic thrombocytopenic purpura (ITP) and HIT. In Section I, Dr. James Bussel discusses CTPs and their distinction from childhood ITP. He emphasizes the clinical features that enable the pediatrician and hematologist to suspect the diagnosis of CTP and those that are of use to subcategorize the various entities, where possible. He also emphasizes newer molecular markers that afford definitive diagnosis in some cases and provide insight into platelet production. This section highlights the characteristic associated findings and differences in the natural history and approaches to management of the various entities. In Section II, Dr. Robert McMillan discusses adult chronic ITP. He revisits the utility of platelet antibody determination in diagnosis and review new insights into pathogenesis. The role of Helicobacter pylori infection and the timing of splenectomy in the management of acute and emergent ITP are examined. New insights into the natural history of ITP post-splenectomy and management strategies for patients with severe, chronic, refractory ITP are discussed. In Section III, Dr. James Zehnder updates us on HIT. He emphasizes new insights into the clinical presentation and pathogenesis of this condition. He critically reviews the utility of laboratory testing for heparin-dependent antibodies. Recent studies on the use of direct thrombin inhibitors are examined and the management of cardiopulmonary bypass surgery in patients with HIT is discussed.