ABSTRACT
Objective:To explore the types, gene mutation types and constituent ratio of thalassemia in Xiaoshan area of Hangzhou, and to analyze the value of test index of erythrocyte parameter calculation formula (Matos & Carvalho Index, MCI) in differential diagnosis.Methods:Using the method of retrospective analysis, 150 cases of thalassemia and 124 cases of iron deficiency anemia treated in Xiaoshan Hospital Affiliated to Hangzhou Normal University from January 2019 to April 2021 were included in the study to collect the diagnostic results of α and β-thalassemia genes, ferritin and erythrocyte parameters, the test indexes were compared and analyzed, and the value of MCI in differentiating thalassemia from iron deficiency anemia was analyzed.Results:In 150 cases of thalassemia, there were 58 cases of α-thalassemia (38.67%), of which 8 cases (5.33%) were complicated with iron deficiency; there were 88 cases of β-thalassemia (58.67%), of which 3 cases (2.00%) were complicated with iron deficiency; αβ-compound thalassemia occurred in 4 cases (2.67%). The proportion of α-thalassemia was lower than β-thalassemia, the difference was statistically significant (χ 2 = 12.01, P = 0.001) . Four kinds of α-thalassemia allele were detected in 58 cases of α-thalassemia, mainly -- SEA, a total of 48 cases (82.76%); eight gene mutation types were detected in 88 cases of β-thalassemia, of which CD41-42 was the most, a total of 33 cases (37.50%). The basic parameters of β-thalassemia, red blood cell (RBC), hemoglobin (HGB) and red blood cell specific volume (HCT) were lower than those of α-thalassemia ( t = - 2.88, - 3.49, - 4.33, P < 0.05); mean hemoglobin concentration (MCHC) and red cell volume distribution width (RDW) were higher than those of α-thalassemia ( t = 3.22, 2.43, P < 0.05). The MCI value of thalassemia group was significantly higher than that of iron deficiency anemia group (23.14 ± 1.73 vs 20.47 ± 1.45, t = 13.61, P < 0.001). The area under the curve of MCI (AUC) = 0.885. The diagnostic cut-off point was set according to the maximum Jorden index method (0.594). The diagnostic cut-off point in this study was 21.375, with a sensitivity of 82.0% and specificity of 77.4%. Conclusions:The genotyping of thalassemia in Xiaoshan area of Hangzhou indicates that β-thalassemia is dominant, with the most mutations in CD41-42 genotype, followed by α-thalassemia, with -- SEA genotype mutation most. MCI has great screening value in identifying small cell anemia.