Aplastic crisis revealing the diagnosis of Hb Evans [α62(E11) Val→Met, GTG→ATG (α2)] in a Hispanic kindred: Case report and review

This report describes a Hispanic girl who presented in aplastic crisis due to parvovirus infection. She was subsequently found to have a chronic hemolytic anemia secondary to an unstable hemoglobinopathy. Genetic testing revealed that the girl and two symptomatic family members had Hb Evans [α62(E11) Val→Met, GTG→ATG (α2)], an unstable hemoglobin (Hb) variant due to a mutation in the α2-globin chain. Hb Evans has been described only once previously, in a Caucasian kindred. Literature review indicates aplastic crisis is a rare initial presentation of unstable hemoglobinopathies and that these disorders are infrequent but important causes of hemolytic anemia in Hispanic patients.