Increase of hemoglobin A₂ in human immunodeficiency virus‐1‐infected patients treated with zidovudine

Abstract

We observed increased hemoglobin A2 (HbA2) levels in an asymptomatic human immunodeficiency virus-1 (HIV1) patient with no previous history of beta-thalassemia. He was treated only with zidovudine (AZT). In an attempt to understand this observation, a retrospective study was initiated to determine whether mean HbA2 levels are higher in AZT-treated patients than in subjects not receiving this drug and to assess if other hematologic alterations are associated with elevated HbA2. One hundred fifty-one HIV-positive cases were investigated; AZT was administered to 81 of them. The mean value of HbA2 was 0.032 (SD +/- 0.005) for the treated group vs. 0.027 (SD +/- 0.004) for the controls. This difference was highly significant (P < 0.001). Twenty-four patients (31%) in the treated group had elevated HbA2 levels vs. none in the controls. Bone marrow toxicity seemed to be more significant in patients with heightened HbA2 values, and HbA2 levels did not increase with CDC clinical stage. We conclude that AZT may be linked to high HbA2 levels in some patients.

Clinical, immunological, and virological outcomes of pediatric antiretroviral therapy in central China

“…Anemia is common in HIV-infected children, and this probably reflects the multifactorial causes involved in the pathogenesis. ART drugs such as AZT and D4T are associated with a transient macrocytic anemia by inhibiting β-globin gene expression in human erythroid progenitor cells [22,23]. Usually, the hemoglobin A2 concentration may be high enough to lead to a misdiagnosis of β-thalassemia trait if the clinician is not aware of this unexpected effect of HIV infection and its treatment.…”

The role of haemoglobin A2testing in the diagnosis of thalassaemias and related haemoglobinopathies

“…Increased levels have been reported in the absence of β thalassaemia trait in a few significant cases of hyperthyroidism (values over 4%),14 in HIV-infected patients treated with antiretroviral therapy, 15 16 by Piero Giordano (personal communication), and in the presence of megaloblastic anaemia 17…”

Implications of increased haemoglobin A2values in HIV positive women in the antenatal clinic

“…However, raised HbA 2 values have been reported in other situations including in normal individuals, 1 unstable haemoglobins, hyperthyroidism, megaloblastic anaemia, 2 and in human immunodeficiency virus (HIV) infected patients on antiretroviral therapy. 3 Of these conditions, only heterozygous b thalassaemia is associated with hypochromic microcytic red cell indices.…”