Fibromyalgia and chronic fatigue syndrome - Similarities and differences

Chronic fatigue syndrome (CFS) and fibromyalgia (FM) are clinical conditions characterized by a variety of nonspecific symptoms including prominent fatigue, myalgia, and sleep disturbances. There are no diagnostic studies or widely accepted pathogenic, explanatory models for either illness. Despite remarkably different diagnostic criteria, CFS and FM have many demographic and clinical similarities. Although few differences exist in the domains of symptoms, examination findings, laboratory tests, functional status, psychosocial features, and psychiatric disorders, FM appears to represent an additional burden of suffering among those with CFS.