en Pediatric Hematology & Oncology Pediatric Hematology & Oncology پژوهشي Original Article Background: The aim of the present study was to assess the mean corpuscular volume (MCV) as a surrogate marker for detecting early iron deficiency prior to definitive investigation and treatment. Materials and Methods: This study was done on one hundred students in Swada Preparatory School – Sharkia Governorate from 2010 to 2011. They were subdivided into three groups: Group (A): comprised of 31 anemic children. Group (B): comprised of 19 microcytic children. Group (C): comprised the control group of 50 apparently healthy children with normal CBC. All subjects were subjected to: full history taking, thorough clinical examination and iron studies including: serum iron , total iron binding capacity, serum ferritin and transferrin saturation. Results: There was a significant difference among studied subjects in height, presence of anorexia and pallor. Moreover, there was a significant difference among studied subjects in Hb, RBCs count, MCH, RDW (p < 0.001) and WBCs count (p= 0.004). We noticed a significant positive correlation between MCV (fl) and serum iron (mg/dl) in anemic subjects. Also there was a significant positive correlation between MCV (fl) and TIBC (μg/dl) in anemic subjects as well as a significant positive correlation between MCV (fl) and serum ferritin (μg/dl). In microcytic subjects, we found a significant positive correlation between MCV (fl) and iron (mg/dl) and a significant positive correlation between MCV (fl) and ferritin (μg/dl). Conclusion: Every child with clinical manifestations of anemia proved by CBC who have microcytosis and low MCV should undergo iron studies ( serum iron, serum ferritin, total iron binding capacity and transferrin saturation ). Keywords: Iron deficiency , anemia, children. Iron deficiency , anemia, children 61 68 http://ijbc.ir/browse.php?a_code=A-10-1-20&slc_lang=en&sid=1 SM Abdelsalam 10031947532846002757 10031947532846002757 Yes ME Awad 10031947532846002758 10031947532846002758 No AE Eldesouky 10031947532846002759 10031947532846002759 No