New concepts in primary fibrositis syndrome.

PFS is a painful rheumatologic disorder that may be detected by the wary clinician attuned to the presence of seven or more tender points. This common disorder may be seen at any age, including childhood, and may be associated with secondary symptoms of depression and other affective disorders. It may also be associated with findings of disturbed sleep, hearing and vestibular abnormalities, and profound complaints of fatigue. The vagueness of this latter complaint means that PFS must be distinguished from the newly described CEBV syndrome. Although the etiology of PFS remains unknown, recent investigations suggest that these patients may suffer a disorder with a central nervous system component as well as a subtle peripheral tissue lesion. Newer PFS studies demonstrate tissue changes that may be consistent with altered microvascular permeability and blood flow, tissue hypoxia, and chronic muscle spasm. An immunologic abnormality, or even a previously undescribed connective tissue disease, may be important as a pathogenic factor in some PFS patients.