IL6 and chronic kidney disease: The direct stimulation of systemic inflammatory burden by uraemic toxins was further supported by the findings from a recent cross-sectional observational study of 149 chronic kidney disease (CKD) patients (mean eGFR 40 ± 9 mL/min/1.73 m2; range 25–59 mL/min/1.73 m2) which showed that serum uraemic toxin levels (i.e., indoxyl sulphate) were significantly and independently associated with serum IL-6, TNF-α, and interferon-γ (IFN-γ) concentrations (unpublished) [37].