CXCL8 and myalgic encephalomeyelitis/chronic fatigue syndrome: However, as stated before, objective results related to a better regulation of the cytokine-HPA-axis induced by the synbiotic was only found in the group of FM patients without a previous diagnostic of CFS (also with basal elevated levels of IL-8); probably suggesting that women with CFS are, sometimes, over-diagnosed with FM via subjective and perceived evaluations.