An improved method for detecting red cells with hemoglobin H inclusions that does not require glass capillary tubes.

alpha-Thalassemia trait is the most common inherited abnormality worldwide. Diagnosis of alpha-thalassemia trait can be difficult as there are no abnormalities detectable by hemoglobin electrophoresis or high-performance liquid chromatography. Detection of individuals with alpha-thalassemia trait, particularly the type present in many Asian populations, is important for genetic counseling purposes, because these individuals are at risk for having offspring with hemoglobin Bart's hydrops fetalis, a fatal condition. The best routine diagnostic method to detect individuals with alpha-thalassemia trait is staining reticulocyte-enriched red cell preparations with brilliant cresyl blue to detect hemoglobin H inclusions. Current methods use centrifugation of microhematocrit tubes to enrich for reticulocytes, which presents a laboratory safety hazard. In this report, we describe an alternative technique to enrich for reticulocytes that does not require glass capillary tubes, but is as effective as the capillary tube method for reticulocyte enrichment and detection of cells containing hemoglobin H inclusions.