Avaliação do estado nutricional e da massa óssea em crianças com anemia falciforme

Abstract

Sickle cell disease (SCD) is the most common hereditary disorder in Brazil and in the world and is characterized by the presence of S hemoglobin in homozigosis. Chronic hemolytic anemia and vaso-occlusion commonly occur and probably contribute to impairment of nutritional status which, in turn, are frequently accompanied by changes in body composition and delayed skeletal maturation. The aim of the present study was to compare nutritional status and bone mass in 2 to 5 years children with and without sickle cell disease. Nutritional status was evaluated by using the following indices: body mass index for age (BMI/age), weight for age (W/A), height for age (H/A) and weight for height (W/H) evaluated as z-scores and adequacies for midupper arm circumference (MUAC), triciptal skinfold thickness (TST) and upper arm muscle circumference (UAMC). Laboratorial analyses included hemoglobin, hematocrit, reticulocyte count, lactate dehydrogenase (LDH), erythrocyte sedimentation rate (ESR), serum iron and transferrin. Bone age was assessed by a left hand and wrist radiograph and bone mass was evaluated by dual energy X-ray absorptiometry (DXA). Fifty two children with SCD and 47 control children were enrolled. In the group of SCD children, considering BMI/age, the prevalence of overweight (7,7% overweight risk and 3,9% overweight) was higher than the prevalence of under nutrition (1,9%). It was observed a higher prevalence of height deficit (13,5%) than weight deficit (3,9%) in the SCD children. Body composition results from DXA showed that total body mass, body fat and percent of body fat were significantly higher in the control group than in the group with SCD (p < 0,001). Based on relative bone age, deficits in skeletal maturation were significantly higher (p <0,01) in the SCD children (-8,9 ± 9,9 months or -0,74 ± 0,83 years) compared with the control group (-2,4 ± 8,5 months or -0,2 ± 0,71 years). Relative bone age was positively associated (P<0,01) with hematocrit and hemoglobin and negatively associated with reticulocyte (p=0,037) and leucocyte (p=0,002) counts and LDH (p=0,002). Although SCD children were predominantly normal weight based on BMI/age, body compartment analysis showed reduced fat and bone masses as well as elevated height deficits consistent with a chronic nutritional deficit. Follow up of nutritional status of children with sickle cell disease must be initiated as early as possible in order to prevent nutritional status impairment