What is your strategy for optimizing hydroxyurea dosage in patients with symptomatic sickle cell disease, particularly for genotypes HbSS and HbS/Beta thal?  

I am far, far more worried about underdosing than overdosing. Although HgF is the traditional lab parameter, it may not go up in all patients. I also look for a decrease in reticulocytes, LDH, indirect bili (less hemolysis), less inflammation (WBC and platelets), and a lowering of MCHC (i.e., fewer ...