RELEVANT LABORATORY FINDINGS IN PATIENTS WITH SICKLE-CELL DISEASE LIVING AT HIGH-ALTITUDE

In an attempt to assess the physiological changes that occur in a pati ent suffering from the sickle cell disease (SCD) and living permanentl y at a high altitude, hematological parameters (hemoglobin concentrati on, RBC count, reticulocyte count, MCH, MCHC, MCV, Hb S, F and A2 leve ls) and biochemical parameters (serum bilirubin, erythrocyte 2,3-DPG, serum iron, TIBC and haptoglobin levels) were measured in patients wit h two sickle cell syndromes (homozygous Hb SS and heterozygous Hb S/be ta0-thalassemia) matched with Hb AA normal controls living at an altit ude of 3000m. These parameters were compared with values obtained in s imilar groups of subjects residing at sea level. Our results confirm t hat normal controls permanently residing at altitude have higher hemog lobin concentrations and erythrocyte 2,3-DPG levels than do normal cou nterparts living at sea level. Patients with SCD living permanently at high altitude show a marked increase in 2,3-DPG levels with little or no change in hemoglobin concentration. Normal serum iron and total ir on binding capacity (TIBC) levels in our patients exclude iron deficie ncy as a possible reason for the poor expected erythropoietic response to altitude. We suggest that the marked rise in 2,3-DPG may be an imp ortant aid to oxygen delivery to tissues of SCD patients living at hig h altitude.