Hb bristol-alesha presenting thalassemia-type hyperunstable hemoglobinopathy

Hemoglobin (Hb) Bristol-Alesha is caused by a GTG→ ATG mutation at codon 67 in the Hb s chain, resulting in abnormal s globin chains with mutated molecules from normal s67 valine (Val) to s67 methionine (Met) or s67 aspartate (Asp). We describe a Japanese child with this rare hemoglobinopathy and a very unstable Hb molecule phenotype. The diagnosis of hemolytic anemia was made when the patient was 6 months of age. Development of marked splenomegaly necessitated red blood cell transfusions twice a month. After splenectomy when the patient was 4 years of age, laboratory findings of hemolytic anemia became more prominent. Specific abnormal Hb molecules initially were not detected, and the α/s globin synthesis ratio was abnormal at 2.22. After splenectomy, we identified the presence of abnormal s-globin chains with a s67Val:s67Met:s67 Asp molecule ratio of 74:11:15. We speculate that the high fraction of the s67Met molecule in this patient, compared with that in previously reported cases, caused extreme Hb instability, which resulted in thalassemic hyperunstable hemoglobinopathy and very severe clinical findings.