Double heterozygous hemoglobin Q India/hemoglobin D Punjab hemoglobinopathy: Report of two rare cases

Abstract

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 α and β 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.