A Unique Case of a Compound Heterozygosity of Hemoglobin Korle-Bu and Sickle Cell Trait in a Military Trainee.

Hemoglobin Korle-Bu (Hb KB) is a rare and likely under-reported hemoglobin (Hb) variant resulting from an unusual point mutation on the beta-globin chain. Hb KB is typically clinically silent, and there are limited reports of Hb KB heterozygosity compounded with other hemoglobinopathies that can present with varying clinical phenotypes. Here, we report a case of compound Hb KB heterozygosity with Hb S in an asymptomatic military trainee with a positive sickle cell screening test. Hb capillary and gel electrophoresis predicted a compound Hb S/D-Punjab overlap, which foretells a severe clinical phenotype. Sequencing of the Hb beta gene HBB demonstrated Hb KB, allowing for a diagnosis that fit his asymptomatic clinical phenotype and allowed for retention in the military.