However, prior to adjustment, TNF-α was increased in the ME/CFS cases compared to the controls (Additional file 1: Table S4B) and plasma levels of leptin, CSF-2, CXCL-8, and TNF-α were higher in the ME/CFS + IBS patients than the controls (Additional file 1: Table S4B). Here, LEP is linked to myalgic encephalomeyelitis/chronic fatigue syndrome.