Análise das alterações laboratoriais relacionadas ao hemograma, à dosagem de bilirrubinas e lactato desidrogenase como fatores preditores de crises vaso-oclusivas em crianças com anemia falciforme

Abstract

Children with sickle cell anemia frequently seek emergency services for treatment of vasoocclusive crises (VOC). The long-term complications of VOC include damage to multiple organs, considerably reduced quality of life, and increased risk of death. Preventive actions for VOC could contribute to better care for these patients. Given this, this study monitored changes in hematological and biochemical tests in children (under 18 years of age) with sickle cell anemia (HbSS) during the occurrence of VOC. Blood count data such as red blood cell count, hemoglobin concentration (Hb), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), red cell distribution width (RDW), reticulocyte count, leukocyte count and platelet count, as well as bilirubin and lactate dehydrogenase (LDH) levels were analyzed. These same tests were assessed at the two appointments preceding the crisis, at which the patient had no complaints of pain or other complications. Patients were subdivided according to whether or not they used hydroxyurea. During the period evaluated, 133 episodes of emergency care were identified, 76 of which were related to VOC. A decrease was observed in the number of red blood cells, hematocrit, hemoglobin levels, MCH, platelets, and eosinophils and an increase in the number of total leukocytes, neutrophils, monocytes, conjugated bilirubin levels in the VOC compared to that found in the routine consultation. Patients who were not taking hydroxyurea had lower hematocrit and MCV values and higher RDW indices during routine consultations, as well as lower hematocrit and MCV levels, higher numbers of monocytes and lymphocytes and higher levels of direct bilirubin during crisis episodes, compared to those who were taking the medication. Values of MCHC, RDW, conjugated bilirubin, and LDH increased significantly in the consultation that preceded the VOC, compared to the routine consultation before it, suggesting that these markers could be indicative of a harbinger of crisis. Because of the findings related to the hematological and biochemical parameters of children with sickle cell anemia during VOC, especially regarding the use of hydroxyurea, we believe that we have been able to help understand the pathophysiology of the disease. The analyses presented here should be extended to establish whether these parameters could be considered predictors of VOC in the entire population of patients with sickle cell anemia.