Chronic Fatigue Syndrome (CFS) and Fibromyalgia Syndrome (FMS) are both believed to be expressions of the same disorder affecting the Hypothalamic Pituitary Adrenal Axis (HPA disorder) and as such, are treated the same in RT.
However, in Chronic Fatigue general fatigue is typically the major symptom.
Also, there is a relatively high incidence of immune symptoms (as compared with FMS) e.g. sore throat, flu-like symptoms, swollen galnds etc.