Inflammatory molecule reduction with hydroxyurea therapy in children with sickle cell anemia

Children with sickle cell anemia (SCA) suffer from a chronic state of inflammation due to repeated tissue insult from sickling red blood cells. The clinical consequences are severe and involve aberration of inflammatory systems, with associated increased activation of multiple cell types, including platelets, neutrophils, and eosinophils.1,2 The literature has described a reduction of inflammatory molecules by hydroxyurea, but results have been limited, and at times contradictory.3–8 In fact, some researchers reported that patients receiving hydroxyurea exhibited increased levels of interleukin (IL)-6 compared to untreated patients,9 while others reported a decrease in IL-6 levels in patients after initiating hydroxyurea therapy,10 albeit neither finding reached statistical significance (perhaps due to small study numbers). Herein, we address discrepancies by reporting a comprehensive study in which 214 patients with SCA were assessed, 122 of whom were sampled longitudinally. We compared patients on hydroxyurea (both initial and sustained therapy) with patients on chronic blood transfusions or no treatment. In grouped analyses, hydroxyurea proved to be the better treatment for reduction of inflammatory molecules. During the 2-year observation period, children continued to benefit from hydroxyurea treatment, although they did not achieve profiles similar to those of healthy controls. Patients receiving continuous chronic blood transfusion therapy or no treatment showed fewer reductions in factor levels compared to hydroxyurea. In total, our data illustrated the long-term, but incomplete benefit of hydroxyurea for reduction of inflammatory molecules in patients with SCA. Abstract source Full text