Ota S, Kotani T, Matsuda S, et al. - Researchers here not only comprehensively assessed serum cytokine levels but also examined the relationship with cerebrovascular lesions on brain magnetic resonance imaging in patients suffering from microscopic polyangiitis (MPA). In the high-grade white matter hyperintensities (WMH) group, significantly higher initial serum granulocyte-macrophage colony-stimulating factor (GM-CSF) levels were detected, vs those in the low-grade WMH group. Multivariate analyses demonstrated independent association of high serum levels of GM-CSF with high-grade WMH. There was a positive correlation of initial serum GM-CSF levels with the Birmingham Vasculitis Activity Score and semi-quantitative scales of WMH. Findings showed an association between initial serum GM-CSF concentrations and the severity of WMH in MPA patients.