Many patients have syndromes for which no specific cause has been identified. Some physicians think that some of these syndromes have psychologic causes, but many physicians and most patients with one of these syndromes reject that idea. Some data—often incomplete, inconsistent, or contradictory—suggest a physical cause, although the exact cause remains uncertain. The causative or contributory role of psychologic factors is also uncertain.

Some patients have scattered, apparently unrelated symptoms that do not form a recognizable syndrome. With better definitions, case recognition may improve; further study of patients with such symptoms is needed to clarify symptom etiology and the clinical significance of these syndromes, to develop appropriate diagnostic strategies, and to define optimum care.

The evaluating physician's first responsibility is to obtain a thorough history, including history of exposure to potentially noxious substances, and to exclude specific, potentially treatable alternative diagnoses. Early stages of known disorders and atypically manifesting common disorders should be considered first. Often, there is little guidance as to what testing is appropriate, but the physician must avoid tests that are inappropriate or not clearly indicated. If no treatable cause is identified after the evaluation, supportive, empathic follow-up is required. A physician should be aware that many patients with such syndromes turn to complementary and alternative medical practices (see Complementary and Alternative Medicine: Overview of Complementary and Alternative Medicine) in their search for relief.

Last full review/revision December 2008 by Margaret-Mary G. Wilson, MD

Content last modified October 2010