Biology of anemia, differential diagnosis, and treatment options in human immunodeficiency virus infection.

Anemia is the most common hematologic manifestation of human immunodeficiency virus (HIV) infection and acquired immunodeficiency syndrome. The causes of HIV-related anemia are multifactorial and include direct and indirect effects of HIV infection. HIV-related anemia generally is due to reduced red blood cell (RBC) production, secondary to a variety of causes, but it may also involve nutritional deficiencies, increased RBC destruction, or a combination of these problems. Evaluation of hemoglobin level, reticulocyte count, bilirubin, and mean corpuscular volume value and review of the peripheral blood smear are necessary for diagnosis. Treatment of HIV-related anemia should address the correctable underlying causes of this disorder, such as modifications of offending medications, nutritional deficiencies, and parvovirus infection. Patients with HIV infection have a blunted erythropoietin response to anemia. Therapeutic modalities for anemia that is not amenable to correction include blood transfusion and recombinant human erythropoietin (epoetin alfa).