A clinical and experimental study of adult hereditary spherocytosis in the Chinese population

Abstract

Hereditary spherocytosis (HS) is often misdiagnosed due to lack of specific diagnostic methods. Our study summarized clinical characteristics and described the diagnostic workflow for mild and moderate HS in Chinese individuals, using data from 20 adults, 8 of whom presented a familial history for HS. We used scanning electron microscopy (SEM) to diagnose HS. We observed reduced eosin maleimide fluorescence activity (5.50 mean channel fluorescence (MCF) units) in the 10 cases of HS, which differed significantly when compared with 10 normal adults (15.50 units), iron deficiency anemia (15.50 MCF units), and megaloblastic anemia (12.00 MCF units) values (P < .05). Next generation sequencing results revealed that 9 out of 10 patients were found to have mutations in the spectrin alpha chain (SPTB), anchor protein (ANK1), and SLC4A1 genes. These mutations were not reported in the Human Gene Mutation Database (HGMD), 1000 human genome, ExAC, and dbSNP147 databases. Splenectomy proved to be beneficial in alleviating HS symptoms in 10 cases. It was found that for the diagnosis of HS, SEM and next generation gene sequencing method proved to be more ideal than red blood cell membrane protein analysis using sodium dodecyl sulfate polyacrylamide gel electrophoresis and western blotting.

Keywords: SLC4A1; ankyrin; hereditary spherocytosis; spectrin; splenectomy.

Figure 1

Peripheral blood morphology of red blood cells (RBCs) with hereditary spherocytosis (HS) (Wright‐Giemsa stain, ×1000). A, Normal RBCs. B, Spherocytes RBCs. C, Hyperchromic RBCs. D, Irregular RBCs. Scanning electron images of RBCs with HS (×4000; scale bar = 10 μm). E, Biconcave‐disk shape of the normal RBCs. F, Irregular shape of RBCs. G, Spherocytes and acanthocytes RBCs. H, Echinocyte RBCs

Figure 2

Mean channel fluorescence for normal controls and patient groups. AIHA, immune hemolytic anemia; HS, hereditary spherocytosis; IDA, iron deficiency anemia; NC, normal control; MA, megaloblastic anemia; MDS, myelodysplastic syndrome

Figure 3

Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE) and western blotting analysis of the red cell membrane proteins with hereditary spherocytosis (1‐14 represents the patient number). A, Spectrin and ankyrin protein existed in SDS‐PAGE electrophoresis. It seemed to be absence of band 3, band 4.1, and band 4.2 protein in varying degrees. B,C, Western blotting analysis showed band 3 protein of patients #13, 14 were significantly reduced compared with normal persons by semi quantitative comparison with gray value, but there is no obvious change in band 4.2 protein of all patients. M, mark; N, normal control

Figure 4

HS diagnostic stepwise process