Relationship of serum lactate dehydrogenase (LDH) levels and history of vasculopathic complications. (A) Kato and colleagues reported LDH levels in 213 patients with sickle cell disease. The frequency distribution by LDH level in hundreds is indicated by the vertical bars. For comparison of the prevalence of selected sickle cell complications, data from 213 patients are divided into three groups according to serum LDH levels. The low LDH is defined by LDH levels lower than one standard deviation below the overall mean (range 121–189 IU/L), medium LDH by overall mean LDH level plus or minus one standard deviation (range 190–511 IU/L) and high LDH higher than one standard deviation above the overall mean (range 512–1171 IU/L). The prevalence of pulmonary hypertension (B), leg ulcers (C), and, in males, priapism (D) are also related to LDH group. All statistics are significant by chi square test for trend. The number of patients in each group (n) is indicated above each bar. Adapted with permission from Blood.⁵⁴