Molecular Genetic Mechanisms of Hereditary Spherocytosis: Current Perspectives.

With the widespread use of genetic diagnostic technologies, many novel mutations have been identified in hereditary spherocytosis (HS)-related genes, including SPTA1, SPTB, ANK1, SLC4A1, and EPB42. However, mutations in HS-related genes are dispersed and nonspecific in the diagnosis of some HS patients, indicating significant heterogeneity in the molecular deficiency of HS. It is necessary to provide the molecular and genetic characteristics of these 5 genes for clinicians to examine HS. Here, we reviewed the recent proposed molecular genetic mechanisms of HS.

Evaluation of a Flow-Cytometric Osmotic Fragility Test for Hereditary Spherocytosis in Chinese Patients.

BACKGROUND: Osmotic fragility testing based on flow cytometry was recently introduced for the screening of hereditary spherocytosis (HS). This study was undertaken to evaluate the clinical diagnostic value of a flow-cytometric osmotic fragility test for HS. METHODS: Peripheral blood was collected from 237 subjects at the First Affiliated Hospital of Guangxi Medical University, including 56 HS patients, 86 thalassemia patients and 95 healthy controls. The samples were examined by flow-cytometric osmotic fragility test and the percentage of residual red blood cells was used to determine HS. Peripheral blood smears were performed to examine the red blood cell morphology. RESULTS: With clinical diagnosis of HS as the gold standard and the percentage of residual red blood cells <23.6% as the diagnostic threshold in the flow-cytometric osmotic fragility test, the sensitivity of the flow-cytometric osmotic fragility test for HS was 85.71% and the specificity was 97.24%. CONCLUSION: The flow-cytometric osmotic fragility test combined with a red blood cell morphology test by peripheral blood smear could be a simple, practical and accurate laboratory screening method for HS.

Comparison and evaluation of three screening tests of hereditary spherocytosis in Chinese patients.

The objective of this study is to compare and evaluate the diagnostic value of hereditary spherocytosis (HS) by three screening tests, comparing mean spherical corpuscular volume (MSCV) to mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), and flow cytometric osmotic fragility test. Peripheral blood was collected from 237 participators diagnosed at the First Affiliated Hospital of Guangxi Medical University, including 56 hereditary spherocytosis patients, 86 thalassemia patients, and 95 healthy people. The samples were examined by three tests, and the three screening tests were evaluated by the sensitivity and specificity of tests. The sensitivity was only 41.07%, and specificity was 94.47% when using MCHC >355 g/L as diagnostic criteria. The sensitivity was 89.28%, and specificity was 96.14% when using MSCV < MCV as the optimum cutoff point. When using the residual red cell percentage <23.6% as the diagnostic threshold in flow cytometric osmotic fragility test, the sensitivity was 85.71% and the specificity was 97.24%. Flow cytometry osmotic fragility test or comparing MSCV to MCV combined with smear examination of peripheral red blood cells morphology can be a simple, practical, and accurate hereditary spherocytosis (HS) laboratory screening method.

Values of mean cell volume and mean sphered cell volume can differentiate hereditary spherocytosis and thalassemia.

OBJECTIVES: To determine whether the values of mean cell volume (MCV) and mean sphered cell volume (MSCV) can distinguish hereditary spherocytosis (HS) from thalassemia. METHODS: The MCV, MSCV, and other erythrocyte indexes were measured in totally 263 people, 57 HS patients, 109 thalassemia patients, and 107 normal control subjects. All indexes were derived from measurements obtained by the Beckman-Coulter LH 750 Hematology Analyzer. RESULTS: The MSCV was significantly lower in the HS group compared with the thalassemia group (P < 0.001), but the MCV was significantly higher in the HS group compared with the thalassemia group (P < 0.001). Among 57 patients with HS, the MCV was higher than the MSCV in 56 patients. The MCV was lower than the MSCV in one patient combined with ß-thalassemia. In the control and thalassemia groups, the MCV was lower than the MSCV. CONCLUSION: Measurements of the MCV higher than the MSCV can be considered an ideal index to distinguish rapidly HS from thalassemia.