RESUMO
Hemoglobin Q-India (α 64 Asp→His) is an important member of the hemoglobin Q family, molecularly characterized by the replacement of aspartic acid by histidine. The first case of Hb Q India was reported by Sukumaran in 1972 in a Sindhi family with associated β-halassemia. India is known as a country with a high prevalence of α - and β-thalassemia and different types of hemoglobinopathy. Many of these variants are yet to be identified. Here, we are reporting two cases of Hb Q- India diagnosed during premarital thalassemia screening.
RESUMO
Cation exchange high performance liquid chromatography (CE HPLC) provides an excellent tool for accurate and reliable diagnosis of various hemoglobin (Hb) disorders. HbQ India is a rare alpha chain variant that usually presents in the heterozygous state. Its presence in double heterozygous state with HbD Punjab is extremely rare. The double heterozygosity for a and b chain variants leads to formation of abnormal heterodimer hybrids, which can lead to diagnostic dilemmas. We report two rare cases of double heterozygous HbQ India/HbD Punjab where the hybrid Hb was seen to elute at retention time similar to HbC on CE HPLC. The first case had unconjugated hyperbilirubinemia at presentation; while, the second case was asymptomatic.