Hepatitis: Stasi R

Cines DB, Liebman H, Stasi R. · University of Pennsylvania School of Medicine, Department of Pathology and Laboratory Medicine, Philadelphia, PA 19104, USA. · Semin Hematol. · Pubmed #19245930 No free full text.

Abstract: Primary immune thrombocytopenic purpura (ITP) remains a diagnosis of exclusion both from nonimmune causes of thrombocytopenia and immune thrombocytopenia that develops in the context of other disorders (secondary immune thrombocytopenia). The pathobiology, natural history, and response to therapy of the diverse causes of secondary ITP differ from each other and from primary ITP, so accurate diagnosis is essential. Immune thrombocytopenia can be secondary to medications or to a concurrent disease, such as an autoimmune condition (eg, systemic lupus erythematosus [SLE], antiphospholipid antibody syndrome [APS], immune thyroid disease, or Evans syndrome), a lymphoproliferative disease (eg, chronic lymphocytic leukemia or large granular T-lymphocyte lymphocytic leukemia), or chronic infection, eg, with Helicobacter pylori, human immunodeficiency virus (HIV), or hepatitis C virus (HCV). Response to infection may generate antibodies that cross-react with platelet antigens (HIV, H pylori) or immune complexes that bind to platelet Fcgamma receptors (HCV), and platelet production may be impaired by infection of megakaryocyte (MK) bone marrow-dependent progenitor cells (HCV and HIV), decreased production of thrombopoietin (TPO), and splenic sequestration of platelets secondary to portal hypertension (HCV). Sudden and severe onset of thrombocytopenia has been observed in children after vaccination for measles, mumps, and rubella or natural viral infections, including Epstein-Barr virus, cytomegalovirus, and varicella zoster virus. This thrombocytopenia may be caused by cross-reacting antibodies and closely mimics acute ITP of childhood. Proper diagnosis and treatment of the underlying disorder, where necessary, play an important role in patient management.

Stasi R. · Department of Medical Sciences, Ospedale Regina Apostolorum, Albano Laziale, Italy. · Semin Hematol. · Pubmed #19245929 No free full text.

Abstract: Secondary thrombocytopenia may result from autoimmune diseases, lymphoproliferative disorders, infections, myelodysplastic syndromes, common variable immunodeficiency, agammaglobulinemia, hypogammaglobulinemia, immunoglobulin A deficiency, and drugs. The presence of thrombocytopenia may result from chronic infections with hepatitis C virus (HCV), human immunodeficiency virus (HIV), and Helicobacter pylori and should be considered in the differential diagnosis of immune thrombocytopenic purpura (ITP). Studies have shown that upon diagnosis of infections, treatment of the primary disease allows for stabilization of platelet counts. Antiviral therapy with highly active antiretroviral therapy (HAART) for HIV has aided in platelet recovery with a corresponding decrease in circulating viral load. In some cases, the use of a thrombopoietin (TPO) agonist, eltrombopag, normalizes platelet levels in patients with these infections. Thrombocytopenia in the absence of other disease symptoms requires screening for H pylori, especially in regions where there is a high prevalence of the disease, such as in Japan, and in cases where platelets have normalized following eradication therapy. In other regions where these infections are not prevalent, such testing is controversial.

Liebman HA, Stasi R. · University of Southern California-Keck School of Medicine, Los Angeles, California, USA. · Curr Opin Hematol. · Pubmed #17934365 No free full text.

Abstract: PURPOSE OF REVIEW: The American Society of Hematology and British Committee for Standards in Haematology guidelines for the diagnosis and management of immune thrombocytopenic purpura focused entirely on primary disease, and secondary forms were not addressed. The guidelines did not address thrombocytopenia resulting from autoimmune disorders or chronic infections such as Helicobacter pylori, hepatitis C virus or HIV. RECENT FINDINGS: Antiphospholipid antibodies can be detected in roughly 50% of patients diagnosed with primary immune thrombocytopenic purpura, and are not associated with distinctive clinical features. The incidence of thrombotic events is controversial. The prevalence of H. pylori infection in adult patients may not be different from that of the general healthy population matched for age and geographical area. Eradication of the infection can produce platelet responses in a variable number of individuals and is less costly and toxic when compared with standard therapy. Finally, patients with risk factors (multiple sex partners, intravenous drug abuse, blood transfusion recipients) and chronic thrombocytopenia should be screened for hepatitis C virus or HIV infection and should be treated for these infections, not immune thrombocytopenic purpura. SUMMARY: In secondary forms of immune thrombocytopenic purpura, when the hematologist plays a consultative role, priority should be treatment of the underlying disorder.