Contributions
Abstract: PB2070
Type: Publication Only
Background
Microcytic anemia is defined as anemia with a low mean corpuscular volume (MCV) for age, race, and sex. The most common causes of microcytic anemia in children are iron deficiency and thalassemia. Iron deficiency and thalassemia are characterized by decreased hemoglobin production, due to insufficient availability of heme or globin, respectively and both cause hypochromic microcytic anemia. Iron deficiency is frequently seen in parts of the world where nutrition is inadequate and the socioecomic status is low. Thalassemias are common in the Mediterranean region. Thalassemia trait may be identified as an incidental finding. Differentiation and detection of coexistence is essential for genetic counselling and to set a treatment plan on the basis of etiology.
Aims
The aim of the study was to characterise the frequency of iron deficiency anemia (IDA) and thalassemia trait among children who presented with microcytic anemia in our pediatric hematology clinic.
Methods
Data were available for 200 children (6 months-18 years) attending the outpatient pediatric hematology clinic between August 2013-July 2014. Screening for iron deficiency was done by analysing serum ferritin, iron and iron binding capasity. Haemoglobin variants were diagnosed by HPLC or capillary electrophoresis and molecular methods.
Results
Of the 200 enrolled, 93 were female (46.5%) and 107 were male (53.5%). Fifty-three children were <2 years of age (26.5%), 52 (26%) between 2-4 years, 56 (28%) between 5-11 years and 39 (19.5%) were >12 years old. One-hundred-fiftyfour had IDA (77%), 27 had thalassemia trait (13.5%), and in 11 both conditions co-existed. Eight of the thalassemia trait patients were found to have an alpha-thallesemia gene mutation, in 3 of these there was also IDA. RBC, MCV, Mentzer index (MI), serum iron, total iron binding capacity, ferritin were significantly different between IDA and thalassemia trait patients (p<0.001) however RDW was not different between the 2 groups (p>0.05). Sensitivity and specifity of MI for detection of thalassemia trait 100% and 69.4% respectively. The positive and negative predictive values of MI in diagnosing thalassemia trait were 36.6 and 100%. In patients with co-existing IDA and thalassemia trait; MI had a sensitivity of 90.9%, specifity of 69.4%, pozitive predictive value of 17.5% and a negative predictor value of 99.7%.
Conclusion
The differentiation between βTT and IDA, requires Hb A2 estimation by Hb electrophoresis, examination of a peripheral blood film, serum ferritin, iron, TIBC, and transferrin saturation. The requirement of simple distinguishing parameters between IDA and thalassemia trait in a child presenting with hypochromic microcytic is needed as several studies have shown the effect of coexistence of IDA on HbA2 synthesis resulting in confusing levels of HbA2 in thalessemia. Hemoglobin electrophoresis is also not helpful in patients with alpha- thalassemia trait.
Session topic: 30. Iron metabolism, deficiency and overload
Keyword(s): Iron deficiency anemia, Thalassemia
Abstract: PB2070
Type: Publication Only
Background
Microcytic anemia is defined as anemia with a low mean corpuscular volume (MCV) for age, race, and sex. The most common causes of microcytic anemia in children are iron deficiency and thalassemia. Iron deficiency and thalassemia are characterized by decreased hemoglobin production, due to insufficient availability of heme or globin, respectively and both cause hypochromic microcytic anemia. Iron deficiency is frequently seen in parts of the world where nutrition is inadequate and the socioecomic status is low. Thalassemias are common in the Mediterranean region. Thalassemia trait may be identified as an incidental finding. Differentiation and detection of coexistence is essential for genetic counselling and to set a treatment plan on the basis of etiology.
Aims
The aim of the study was to characterise the frequency of iron deficiency anemia (IDA) and thalassemia trait among children who presented with microcytic anemia in our pediatric hematology clinic.
Methods
Data were available for 200 children (6 months-18 years) attending the outpatient pediatric hematology clinic between August 2013-July 2014. Screening for iron deficiency was done by analysing serum ferritin, iron and iron binding capasity. Haemoglobin variants were diagnosed by HPLC or capillary electrophoresis and molecular methods.
Results
Of the 200 enrolled, 93 were female (46.5%) and 107 were male (53.5%). Fifty-three children were <2 years of age (26.5%), 52 (26%) between 2-4 years, 56 (28%) between 5-11 years and 39 (19.5%) were >12 years old. One-hundred-fiftyfour had IDA (77%), 27 had thalassemia trait (13.5%), and in 11 both conditions co-existed. Eight of the thalassemia trait patients were found to have an alpha-thallesemia gene mutation, in 3 of these there was also IDA. RBC, MCV, Mentzer index (MI), serum iron, total iron binding capacity, ferritin were significantly different between IDA and thalassemia trait patients (p<0.001) however RDW was not different between the 2 groups (p>0.05). Sensitivity and specifity of MI for detection of thalassemia trait 100% and 69.4% respectively. The positive and negative predictive values of MI in diagnosing thalassemia trait were 36.6 and 100%. In patients with co-existing IDA and thalassemia trait; MI had a sensitivity of 90.9%, specifity of 69.4%, pozitive predictive value of 17.5% and a negative predictor value of 99.7%.
Conclusion
The differentiation between βTT and IDA, requires Hb A2 estimation by Hb electrophoresis, examination of a peripheral blood film, serum ferritin, iron, TIBC, and transferrin saturation. The requirement of simple distinguishing parameters between IDA and thalassemia trait in a child presenting with hypochromic microcytic is needed as several studies have shown the effect of coexistence of IDA on HbA2 synthesis resulting in confusing levels of HbA2 in thalessemia. Hemoglobin electrophoresis is also not helpful in patients with alpha- thalassemia trait.
Session topic: 30. Iron metabolism, deficiency and overload
Keyword(s): Iron deficiency anemia, Thalassemia