Aa refers to pancytopenia in association with bone marrow. In most cases of aplastic anemia, these triggers, or other unknown causes, provoke the bodys own immune system to destroy the bone marrow stem cells. From epidemiologic and clinical features, pathophysiologic studies, and response to therapy, aa is a distinctive disease. There are no specific tests that can be used to identify with certainty the cause of the aplastic anaemia in any particular case. Relationship of medical drug use to aa is due to deletions in the drugmetabolizing glutathiones transferase genes. Vitamin deficiency anemia due to low levels of vitamins c, b12, or folate. The last several years have seen exciting developments in the study of. Pathophysiology of aplastic anaemia wiley online library. Anemia healthy changes national heart, lung, and blood. Blood cells are produced in the bone marrow by stem cells that reside there. Review article druginduced megaloblastic, aplastic, and. Aplastic anemia treatment at danafarberboston childrens children and young adults with aplastic anemia are treated at danafarberboston childrens through our bone marrow failure program. Although most cases are acquired, there are unusual inherited forms.
This is a pdf file of an unedited manuscript that has been accepted. Aplastic anemia aa is a lifethreatening form of bone marrow failure which, if untreated, is associated with very high mortality. Frontiers pathogenesis of acquired aplastic anemia and. Epidemiology, pathogenesis and diagnosis of aplastic anaemia. Aplastic anemia aa, the paradigm of the bone marrow bm failure syndromes, is most simply defined as peripheral blood pancytopenia and a hypocellular bm fig. Many diseases and conditions can damage the stem cells in bone marrow. Aplastic and hypoplastic anemias american academy of. Absence of hematopoietic cells has been recognized from the characteristic morphology for a century.
New insights into the pathophysiology of immunemediated marrow failure. Characterisation of anemia and erythrocytosis in relation to serum erythropoietin levels can be a useful addition to clinical diagnostic criteria and provide a rationale for treatment with erythropoiesis. Antigens are presented to t cells by antigenpresenting cells apcs, which trigger t cells to activate and proliferate. New methods to culture haemopoietic cells, and advances in our knowledge of. Aplastic anaemia is a rare haemopoietic stemcell disorder that results in pancytopenia and hypocellular bone marrow. Current concepts in the pathophysiology and treatment of aplastic anemia. Pdf an immune basis for most patients with aplastic anemia aa provides a rationale for immunosuppressive therapy ist, using.
Characterisation of anemia and erythrocytosis in relation to serum erythropoietin levels can be a useful addition to clinical diagnostic criteria and provide a rationale for treatment with erythropoiesis stimulating agents esas. Aplastic anemia, idiopathic aplastic anemia, congenital aplastic anemia, autoimmunity, hypocellular. Aplastic anemia, which occurs when the bone marrow fails to produce enough red blood cells. In short, the text provides an accurate and comprehensive overview of aplastic anemia. Updates on the pathophysiology and treatment of aplastic anemia. Anemia may result from blood loss, a destructive process ie, hemolysis, nutritional deficiency, or poor production eg, ineffective erythropoiesis or hypoplastic or aplastic marrow table.
Aplastic anemia current medical diagnosis and treatment. Acquired means you arent born with the condition, but you develop it. Aplastic anemia is a disorder of the hematopoietic stem cell that results in a loss of blood cell precursors, hypoplasia or aplasia of bone marrow, and cytopenias in two or more cell lines red blood cells, white blood cells, andor platelets. The authors, mostly from the european group for blood and marrow transplantation. There may be a lack of all cell typeswhite blood cells leukocytes, red blood cells. Bone marrow is a red, spongy material inside your bones that produces stem cells, which give rise to other cells.
Stem cells in the bone marrow produce blood cells red cells, white cells and platelets. Aplastic anemia is an autoimmune disease in which the body fails to produce blood cells in sufficient numbers. The common pathology of the bone marrow replaced by fat can result from chemical or physical damage. Aplastic anemia develops when damage occurs to your bone marrow, slowing or shutting down the production of new blood cells.
The linking of constitutional bm failure to acquired aplastic anemia aa through genetic defects in telomere repair has provided the likely explanation for the troubling evolution from an inflammatory pathophysiology, t cellmediated bm destruction, to malignant hematologic diseases like myelodysplastic syndrome mds and acute myelogenous. Aplastic anemia is a syndrome of bone marrow failure characterized by peripheral pancytopenia and marrow hypoplasia see the image below. At least 2 of the following peripheral cytopenias must be present. Aa refers to pancytopenia in association with bone marrow hypoplasiaaplasia, most often due to immune injury to multipotent hematopoietic stem cells. There are a number of causes of aplastic anemia table 10. Current concepts in the pathophysiology and treatment of. Aplastic anemia in children danafarberboston children. Hemolytic anemia, a condition where the body destroys red blood cells prematurely. Inherited means your parents passed on the gene for the condition to you. Pathophysiologic mechanisms in acquired aplastic anemia. The linking of constitutional bm failure to acquired aplastic anemia aa through genetic defects in telomere repair has provided the likely explanation for the troubling evolution from an inflammatory pathophysiology. Aplastic anemia aa is characterized by bone marrow bm hypocellularity, resulting in peripheral cytopenias. However, the diagnosis of aa requires excluding other causes.
An immune basis for most patients with aplastic anemia aa provides a rationale for immunosuppressive therapy ist, using antithmyocyte globulin and cyclosporine as one therapeutic. Constitutional aplastic anemia see pathophysiology clinical features signs and symptoms related to presence and severity of cytopenias i. The linking of constitutional marrow failure to acquired aplastic anemia through genetic defects in telomere repair has provided the likely explanation for the troubling evolution from an inflammatory pathophysiology, t cellmediated marrow destruction, to malignant hematologic diseases like myelodysplasia mds and acute myeloid leukemia. The pathophysiology of acquired aplastic anemia nejm. Describe the metabolic and physiologic responses to anemia.
It comprises a group of patho genetically heterogeneous bone marrow failures and is characterized by a bi or tricytopenia thrombocytopenia, anemia. Certain rare, inherited bone marrow failure syndromes can also lead to aplastic anemia. Journal of the national cancer institute this book provides comprehensive and up to date concepts on the pathophysiology, epidemiology, diagnosis and treatment of acquired and inherited aplastic anemia. Direct hematopoietic stem cell injury may be caused by radiation, chemotherapy, toxins, or pharmacologic agents. An antigendriven and likely autoimmune dysregulated tcell homeostasis results in. An immune basis for most patients with aplastic anemia aa provides a rationale for immunosuppressive therapy ist, using antithmyocyte globulin and cyclosporine as one therapeutic modality. The introduction of potentially harmful medical drugs such as chloramphenicol or phenyl butazone has renewed interest in the pathogenesis of aplastic anaemia. Aplastic anemia is graded primarily on peripheral blood count values into 1 severe aplastic anemia saa. Druginduced aplastic anemia aplastic anemia synonyms. In most children with aplastic anemia, the condition develops after birth. This intense study of aplastic anemia has led to novel advances in bone marrow transplantation, autoimmunity, and hematopoiesis.
Doctors think it happens when a childs immune system stops their bone marrow from making new blood cells. Pathophysiology and treatment is a new multiauthored textbook that is devoted to covering the basic biology and management of acquired aplastic anemia and fanconis anemia. Aplastic anemia aa is defined by pancytopenia with hypocellular marrow and no abnormal cells. Recombinant human erythropoietin as well as other esas are now widely used. That aplastic anemia is perhaps the most dreaded idiosyncratic complication of drug treatment has serious and often expensive consequences for drug development, for risk assessment, for approval.
Gstm1, gstt1, that permit accumulation of toxic drug intermediates. Aplastic anemia, an unusual hematologic disease, is the paradigm of the human bone marrow failure syndromes. Regardless of the instigating event, the physiology driving the pathology of aplastic anemia appears to be autoimmune in nature. Your guide to understanding aplastic anemia this essential primer for patients and families on aplastic anemia covers causes, symptoms, classifications, treatments, and much more. The linking of constitutional marrow failure to acquired aplastic anemia through genetic defects in telomere repair has provided the likely explanation for the troubling evolution from an inflammatory pathophysiology. Aplastic anemia occurs because of damage to stem cells inside bone marrow, which is the spongelike tissue within your bones. Despite all the difficulties in deciding whether a given factor may have caused the aplastic.
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