Carranza-León DA, Oeser A, Marton A, et al. - Researchers assumed that muscle and skin Na⁺ content is (a) higher in individuals with systemic lupus erythematosus (SLE) than in control subjects, and (b) correlated with blood pressure, disease activity, and inflammation markers (interleukin (IL)-6, IL-10 and IL-17 A) in SLE. Lower-leg skin and muscle Na⁺ content were estimated in 23 individuals with SLE and in 28 control individuals using 23Na⁺ magnetic resonance imaging. Demographic and clinical information was obtained from interviews and chart review and blood pressure was assessed. They assessed disease activity using the SLE Disease Activity Index. Plasma inflammation markers were estimated by multiplex immunoassay. Compared with control subjects, individuals with SLE had higher muscle Na⁺ content. The results displayed that higher muscle Na⁺ content was correlated with higher disease activity and IL-10 concentrations in individuals with SLE.