Therapeutic strategies for hepatitis- and other infection-related immune thrombocytopenias.

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.