Evaluation of value of hematological parameters in diagnosis of thalassemia in different age groups

Objective:To evaluate the values of mean corpuscular volume(MCV),mean corpuscular hemoglobin(MCH) and standard deviation of red blood cell volume distribution width(RDW-SD) in detection of thalassemia in different age groups by diagnostic laboratory parameters.Methods:5 564 cases in different age groups were selected,and 1 166 cases were suspected of thalassemia,including 780 adults,260 children and 126 neonates;336 adults,110 children and 21 children were diagnosed as thalassemia definitely by gene diagnosis;SYSMEX SF-3000 analyzer was used to detect MCV,RDW-SD and MCH;Gap-PCR method and PCR-RDB method were used for gene diagnosis of α-thalassemia and β-thalassemia;the results of gene diagnosis were used as gold standards,diagnostic laboratory parameters were used to analyze the values of above-mentioned hematological parameters in diagnosis of thalassemia in different age groups.Results:The areas under ROC curve of MCV,MCH and RDW-SD for diagnosis of thalassemia in adult group were 0.917,0.895 and 0.869,respectively;the areas under ROC curve of MCV,MCH and RDW-SD for diagnosis of thalassemia in child group were 0.965,0.956 and 0.778,respectively;the areas under ROC curve of MCV,MCH and RDW-SD for diagnosis of thalassemia in neonate group were 0.873,0.806 and 0.774,respectively.The optimal thresholds of MCV,MCH and RDW-SD for diagnosis of thalassemia in adult group were 75.45 fl,23.65 pg and 36.76 fl,respectively;the optimal thresholds of MCV,MCH and RDW-SD for diagnosis of thalassemia in child group were 68.95 fl,21.70 pg and 33.75 fl,respectively;the optimal thresholds of MCV,MCH and RDW-SD for diagnosis of thalassemia in neonate group were 96.30 fl,32.85 pg and 55.45 fl,respectively.The negative predictive values of MCV,MCH and RDW-SD for diagnosis of thalassemia in adult group were 99.3%,99.2% and 97.5%,respectively;the negative predictive values of MCV,MCH and RDW-SD for diagnosis of thalassemia in child group were 99.5%,99.3% and 97.0%,respectively;the negative predictive values of MCV,MCH and RDW-SD for diagnosis of thalassemia in neonate group were 99.0%,99.4% and 99.0%,respectively.The positive likelihood ratios of MCV,MCH and RDW-SD for diagnosis of thalassemia in adult group were 15.1,11.0 and 9.53,respectively;the positive likelihood ratios of MCV,MCH and RDW-SD for diagnosis of thalassemia in child group were 17.3,17.2 and 13.8,respectively;the positive likelihood ratios of MCV,MCH and RDW-SD for diagnosis of thalassemia in neonate group were 16.3,20.8 and 13.5,respectively.The negative likelihood ratios of MCV,MCH and RDW-SD for diagnosis of thalassemia in adult group were 0.08,0.10 and 0.28,respectively;the negative likelihood ratios of MCV,MCH and RDW-SD for diagnosis of thalassemia in child group were 0.06,0.12 and 0.35,respectively;the negative likelihood ratios of MCV,MCH and RDW-SD for diagnosis of thalassemia in neonate group were 0.31,0.20 and 0.30,respectively.Conclusion:The values of MCV,MCH and RDW-SD in diagnosis of thalassemia in different age groups are good,the value of MCV is the highest;the optimal thresholds of MCV,MCH and RDW-SD for diagnosis of thalassemia in adults,children and neonates are obviously different.