CXCL8 and dopa-responsive dystonia due to sepiapterin reductase deficiency: Sonoda [13] et al. divided DME into groups with and without SRD, and demonstrated that IL-6 and IL-8 levels were significantly greater in eyes with SRD than in eyes without SRD, IL-6 levels were significantly associated with the presence of SRD after adjusting for age and sex.