New Formula for the Differentiation Between Iron Deficiency Anemia and Thalassemic Carrier in Thalassemic Prevalence Areas: A Study in Healthy School-Age Children.

Abstract

1410 Poster Board I-432 INTRODUCTION: In Thailand, the prevalences of iron deficiency anemia (IDA) and thalassemia carrier are high in the range between 20-50%. Screening of both disorders may show the similar results of low hemoglobin (Hb) and mean corpuscular volume (MCV). Therefore, additional laboratory investigations such as ferritin level, percentage of iron saturation, Hb analysis and DNA study may be required for the definite diagnosis, resulting in an increased cost. Previous studies have identified several formulas to differentiate between IDA and thalassemia carrier by using red blood cell (RBC) parameters. However, individual formula may not applicable for particular population. This study aims to establish a formula to differentiae between IDA and thalassemia carrier in school-age children in central Thailand where the prevalences of β and α thalassemia carriers are high. METHODS: After informed consent, blood was collected and tested for complete blood count (CBC), ferritin level, iron level, total iron binding capacity level, Hb analysis, and DNA study for α- thalassemia-1 (or Southeast-Asian deletion). IDA was diagnosed according to the WHO criteria. Iron deficient erythropoiesis (IDE) was defined as normal hemoglobin (Hb) level and low percentage of iron saturation or ferritin levels. Subjects diagnosed of IDA and thalassemia carrier were selected for further analysis. RESULTS: Three hundred and forty-five healthy children, aged (mean±SD) 11.3±1.7 years, were enrolled in the study. The prevalences of IDA, IDE, thalassemia trait (β, a-thalassemia-1, Hb Constant Spring and HbE trait), thalassemia disease (Hb H, β/E and Hb EE), and normal subjects were 11.6%, 38.3%, 26.1%, 2.3% and 28.7%, respectively. The red blood cell (RBC) parameters of normal, IDA, IDE, HbE trait, β trait and α trait groups were shown in the table below. The median (range) values of serum ferritin level in IDA {37.3 (92.6-162.4)}, IDE {34.3 (3-268.2)} groups were significantly different when compared to normal subjects {46.9 (13.4-232.9)}, p<0.001. However, serum ferritin level alone was not enough for the diagnosis of IDA (area under ROC curve of 0.4). Various reported formulas were used to calculate the area under ROC curve, England and Fraser, 0.78; Mentzler, 0.6; Ehsani, 0.57; Shine-Lai, 0.51; RDW/RBC, 0.88; Srivastava, 0.63; RDWI, 0.79; Green and King, 0.82 and RDW, 0.69. The RDW/RBC had the highest area under ROC curve (0.88). Further analysis of the result to differentiae IDA and thalassemia carrier showed that the RDW/RBC value of ≥3 had the sensitivity and specificity of 82.4% and 88.1%, respectively, in our studied subjects. CONCLUSION: Other than the history of iron intake and thalassemia disease in the family, RDW/RBC≥3 may be an additional test to differentiate between IDA and thalassemia carrier in Thai population. In the future, the validity of this formula in a larger scale of population is recommended. Disclosures: No relevant conflicts of interest to declare.

Reticulocyte hemoglobin equivalent in a thalassemia‐prevalent area

“…17,18 In the present study, the high prevalence of IDA observed in the school-aged group was similar to that observed in a previous study in 2014. 5 The Ret-He level observed in the present NC group was slightly lower compared with that in adults. 6,9 This is expected because the Hb level in children is typically lower than in adults.…”

“…[1][2][3][4] In Thailand, a 2012 study in school-aged children reported incidence rates of ID and iron deficiency anemia (IDA) at 38% and 12%, respectively, while the incidence rates of thalassemia trait and disease in these populations were reported at 32% and 3%, respectively. 5 Currently, the diagnosis of IDA and of thalassemia typically involves the use of traditional hematology parameters. Because both diseases share similar hematological findings of low hemoglobin (Hb) and mean corpuscular volume (MCV), further testing should be done in order to differentiate between the two diseases, namely, iron study, Hb typing, and genetic testing.…”

“…These reticulocyte indices are early indicators of iron incorporation into the red cell Hb and thus estimate the recent functional availability of iron in the erythrocyte. 5 The Sysmex XN-series Ret-He measurement utilizes fluorescence flow cytometry, while the Siemens ADVIA uses cellular volume and light absorption to measure CHr. [6][7][8] The Ret-He and CHr parameters are significantly correlated with each other (r 2 = 0.83-0.88).…”

Anemia Modelling Using the Multiple Regression Analysis

“…So, our goal is to develop a new mathematical model to study the effect of the blood variables, sex, and age on the types of anemia. Our model, different from the mathematical models given in the literature [15][16][17][18][19], has also been successfully used in the prediction of several types of anemia through a large group of blood variables, sex, and age.…”

“…In the literature, many studies were carried out [16,18,[21][22][23] by using relatively less number of input variables to predict the type of anemia. The methods used in the corresponding studies produced relatively less accurate results.…”