From the Guidelines
Acute anemia in HIV patients is primarily caused by undernutrition, micronutrient deficiencies, and opportunistic infections, which can lead to growth impairment and increased morbidity and mortality. The underlying causes of acute anemia in HIV infection can be multifactorial, including:
- Undernutrition, which increases the risk of infections and delays HIV recovery 1
- Micronutrient deficiencies, such as iron, folate, and vitamin B-12, which can result in anemia and growth impairment 1
- Opportunistic infections, such as tuberculosis, oral and esophageal candidiasis, pneumonia, skin infections, and persistent diarrhea, which can worsen anemia and increase mortality 1
- HIV-related bone marrow suppression, which can lead to decreased erythropoiesis and anemia 1
- Inflammation, which can alter iron biomarkers, such as ferritin, and increase the risk of anemia 1
Initial workup for acute anemia in HIV patients should include:
- Complete blood count with differential
- Reticulocyte count
- Iron studies, including soluble transferrin receptor (sTfR) 1
- Vitamin B12 and folate levels
- Evaluation for hemolysis
Treatment for acute anemia in HIV patients should focus on addressing the underlying cause, optimizing HIV control with effective antiretroviral therapy, and managing symptoms. Iron deficiency anemia can be treated with oral ferrous sulfate 325 mg three times daily for 3-6 months, and vitamin B12 deficiency can be treated with cyanocobalamin 1000 mcg daily orally or intramuscularly for one week, then weekly for one month, followed by monthly maintenance. Erythropoietin (epoetin alfa 40,000-60,000 units subcutaneously weekly) may be beneficial for patients with endogenous erythropoietin levels <500 mU/mL. Throughout treatment, it's essential to monitor and optimize HIV control, as improved immune function often helps resolve anemia 1.
From the Research
Causes of Acute Anemia in HIV Infection
The causes of acute anemia in Human Immunodeficiency Virus (HIV) infection are multifactorial, including:
- Direct and indirect effects of HIV infection 2
- Reduced red blood cell (RBC) production 2, 3
- Nutritional deficiencies, such as deficiency of vitamin B12, folate, and iron 3, 4
- Increased RBC destruction 2
- Opportunistic complications 3, 4
- Iatrogenic anemia induced by myelosuppressive drugs 3
- Alteration in hematopoiesis induced by HIV itself 4
- AIDS-associated malignancies 4
Pathogenesis of Anemia in HIV Infection
The pathogenesis of anemia in HIV infection is complex and involves:
- Direct infection of erythroid progenitors 3
- Soluble factors like HIV proteins and cytokines that inhibit growth of hematopoietic cells in the bone marrow 3
- Blunted erythropoietin feedback mechanism 3, 5
- Inadequately low endogenous erythropoietin concentrations 3
Clinical Management of Anemia in HIV Infection
Clinical management of anemia in HIV infection involves:
- Evaluation of hemoglobin level, reticulocyte count, bilirubin, and mean corpuscular volume value 2
- Review of the peripheral blood smear 2
- Treatment of underlying causes, such as modifications of offending medications, nutritional deficiencies, and parvovirus infection 2
- Use of recombinant human erythropoietin (r-HuEPO) to elevate hematocrit values and reduce transfusion requirements 6, 5
- Blood transfusions for immediate correction of hemoglobin levels 2, 6