RESUMO
BACKGROUND: Microcytic anemia, the most common form of anemia in children and adolescents, is a heterogeneous group of diseases that is acquired or inherited. We assessed the frequency and causes of microcytosis in children and adolescents with the sickle cell trait (SCT). METHODS: This descriptive study included 95 subjects (49 males and 46 females) with SCT who attended Basra Center for Hereditary Blood Diseases for evaluation. Investigations included complete blood count, high performance liquid chromatography, capillary electrophoresis, and measurement of serum ferritin and transferrin levels. RESULTS: SCT subjects had a low hemoglobin (Hb) concentration (9.79±1.75 g/dL), low mean corpuscular volume (MCV, 67.43±9.22), low mean corpuscular Hb (21.15±3.64), and a normal red cell distribution width (RDW, 14.00±2.30). Among 95 SCT subjects, 81 (85.26%) had microcytosis, 12 (12.63%) had normal MCV, and 2 (2.11%) exhibited macrocytosis. Sixty-three (77.78%) SCT subjects with microcytosis were iron deficient, and 18 (22.22%) had normal iron levels. The mean serum ferritin and HbA2 levels were significantly lower, while the RDW, sickle Hb, and serum transferrin levels were significantly higher in patients with microcytosis and iron deficiency compared to non-iron deficient subjects (P0.05). CONCLUSION: Despite the frequent occurrence of iron deficiency in SCT subjects, co-inheritance of alpha-thalassemia seemed to be the cause of low MCV in non-iron deficient individuals with microcytosis. Genetic analysis is required to understand the genetic basis of this phenomenon.