Effect of red cell exchange transfusion on plasma levels of inflammatory mediators in sickle cell patients with acute chest syndrome

Abstract

Red cell exchange transfusion is the recommended therapy for patients with sickle cell disease (SCD) who have severe, progressive acute chest syndrome (ACS). A double-volume red cell exchange transfusion decreases the percentage of hemoglobin S (Hgb S) containing red blood cells to less than 20%, improving vascular perfusion. We speculated that reduction of pro-inflammatory mediators might also contribute to the therapeutic effect of an exchange transfusion. We measured white blood cell count (WBC), absolute neutrophil count (ANC), platelet concentration as well as plasma levels of interleukin-1a (IL-1a), interleukin-1b (IL-1b), tumor necrosis factor-a (TNF-a), interleukin-8 (IL-8), and soluble vascular cell adhesion molecule-1 (sVCAM-1) in 8 sickle cell patients with 9 episodes of ACS who received a manual, double-volume exchange transfusion. Six patients with SCD seen during a routine clinic visit were used as controls. The mean number of hospitalization days was 6, with an average of 2 days in the intensive care unit. All patients recovered without complication. Sickle cell patients with ACS had a higher WBC and ANC at baseline but lower sVCAM-1 levels compared to controls. TNF-a, IL-1a, IL-1b, and IL-8 levels were not significantly different from controls. WBC, ANC, platelet, and sVCAM-1 measurements were significantly decreased immediately post-exchange in patients with ACS; however, this effect was not persistent as levels trended towards pre-exchange values by 24 hr post-exchange. Due to wide inter-individual variability, a consistent pattern was not seen for TNF-a, IL-1a, IL-1b, or IL-8. We conclude that in sickle cell patients with ACS, a manual, double-volume exchange transfusion lowers WBC, ANC, platelets, and sVCAM-1 levels, but the effect is short-lived.

Corticosteroids and increased risk of readmission after acute chest syndrome in children with sickle cell disease

“…In a small study of manual exchange transfusion for ACS, plasma levels of vascular cell adhesion molecule-1 (VCAM-1) decreased immediately and then increased to greater than the baseline level after 24 hr, without evidence of rebound pain [20]. Transfusion has well documented adverse effects in SCD, including acute and delayed hemolysis, hyperviscosity, allergic reactions, the transmission of infections, sensitization to red cell antigens, and iron overload [21].…”

Coronary Artery Ectasia in Atherosclerotic Coronary Artery Disease, Inflammatory Disorders, and Sickle Cell Disease

“…Therefore, the pathogenetic mechanism here may be, at least partially, due to the inflammatory process associated with Hb S in SCD [7]. It is important to note that the higher the Hb S percentage is, the more severe the inflammatory state is, and possibly the more likely those patients are to have CAE [7,20,50]. Because different SCT carriers can have a wide range of Hb S percentages and thus have different severities, not all carriers are completely free from inflammation.…”

“…If physically unfit, patients should be warned against acute bouts of strenuous physical activity. In complicated cases of SCD, chronic blood transfusion therapy decreases inflammation and may be helpful, especially in anemic patients [50,73]. Along with the general medical therapies discussed earlier in inflammatory CAE, certain medical therapies may be beneficial for this specific population.…”

Bone marrow embolism in sickle cell disease: A review

“…We believe that exchange transfusion is superior to simple transfusion since multiple simple transfusions can raise blood viscosity and potentiate the effects of sickling on bone marrow necrosis. Exchange transfusion may also dilute inflammatory markers temporarily possibly to clinical advantage [88]. The diagnosis should be considered in sickle cell crisis when accompanied by rapidly deteriorating respiratory signs, a fall in PaO 2 , the presence of numerous circulating normoblasts in peripheral blood smear, and thrombocytopenia, as recommended in a previous report [32].…”