Encyclopedia of Behavioral Medicine

Living Edition
| Editors: Marc Gellman

Medically Unexplained Symptoms

  • Benjamin H. NatelsonEmail author
Living reference work entry
DOI: https://doi.org/10.1007/978-1-4614-6439-6_416-2



A set of patient complaints that with careful history, physical examination, and lab testing has no apparent medical cause is thus unexplained. When this happens, some physicians jump to a psychiatric explanation in lieu of no other - often leaving the patient stigmatized. Instead, a group of experts has arrived at operational definitions of symptom-based syndromes to allow for diagnosis and research. When the symptom is predominantly fatigue, severe enough to reduce activity substantially, and lasting at least 6 months, the diagnosis is idiopathic chronic fatigue. When the symptom is predominantly body-wide pain, also lasting many months, and the patient is tender on palpation, the diagnosis is fibromyalgia. When the pain is limited to face and jaw, the diagnosis is temporomandibular joint syndrome, and when the pain is in the abdomen and associated with constipation and/or diarrhea, the diagnosis is irritable bowel syndrome. The fact that patients with one of these syndromes often have at least one other has supported the psychiatric interpretation of these being variants of somatization disorder (Barsky and Borus 1999). However, data are accumulating that differences do exist among these syndromes (Evengård et al. 1998; Weaver et al. 2010), and focus on pathogenesis has gradually shifted from the focal areas in the body affected to the brain with the notion that nociceptive systems are dysregulated (Schweinhardt et al. 2008). Functional brain imaging studies show patients with widespread pain and chronic fatigue, respectively, to have much larger responses to painful or fatigue-producing stimuli than control subjects (Cook et al. 2004; Lange et al. 2005) - suggesting a sensitized response to these stimuli. Another major factor influencing thinking about these syndromes in the physician community is the emergence of nationally approved drugs that effectively treat the symptoms of some of these disorders. All of this work suggests that, at least for some patients, the pathophysiological process underlying these syndromes is not the same. In addition to these newly available drugs, patients report substantial symptomatic improvement with a program of gentle physical conditioning (Hauser et al. 2010); similarly, providing patients behavioral ways to cope with chronic symptoms via cognitive behavioral therapy (Price et al. 2008) also can help with symptom reduction and improve health-related quality of life.


References and Further Reading

  1. Barsky, A. J., & Borus, J. F. (1999). Functional somatic syndromes. Annals of Internal Medicine, 130(11), 910–921.CrossRefGoogle Scholar
  2. Cook, D. B., Lange, G., Ciccone, D. S., Liu, W. C., Steffener, J., & Natelson, B. H. (2004). Functional imaging of pain in patients with primary fibromyalgia. Journal of Rheumatology, 31(2), 364–378.PubMedGoogle Scholar
  3. Evengård, B., Nilsson, C. G., Lindh, G., Lindquist, L., Eneroth, P., Fredrikson, S., et al. (1998). Chronic fatigue syndrome differs from fibromyalgia. No evidence for elevated substance P levels in cerebrospinal fluid of patients with chronic fatigue syndrome. Pain, 78(2), 153–155.CrossRefGoogle Scholar
  4. Hauser, W., Klose, P., Langhorst, J., Moradi, B., Steinbach, M., Schiltenwolf, M., et al. (2010). Efficacy of different types of aerobic exercise in fibromyalgia syndrome: A systematic review and meta-analysis of randomised controlled trials. Arthritis Research & Therapy, 12(3), R79.CrossRefGoogle Scholar
  5. Lange, G., Steffener, J., Bly, B. M., Cook, D. B., Christodoulou, C., Liu, W. C., et al. (2005). Chronic fatigue syndrome affects verbal working memory: A BOLD fMRI study. NeuroImage, 26(2), 513–524.CrossRefGoogle Scholar
  6. Price, J. R., Mitchell, E., Tidy, E., & Hunot, V. (2008). Cognitive behaviour therapy for chronic fatigue syndrome in adults. Cochrane Database of Systematic Reviews, (3), CD001027.Google Scholar
  7. Schweinhardt, P., Sauro, K. M., & Bushnell, M. C. (2008). Fibromyalgia: A disorder of the brain? The Neuroscientist, 14(5), 415–421.CrossRefGoogle Scholar
  8. Weaver, S. A., Janal, M. N., Aktan, N., Ottenweller, J. E., & Natelson, B. H. (2010). Sex differences in plasma prolactin response to tryptophan in chronic fatigue syndrome patients with and without comorbid fibromyalgia. Journal of Women’s Health, 19(5), 951–958.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Pain Medicine & Palliative CareBeth Israel Medical Center and Albert Einstein College of MedicineBronxUSA

Section editors and affiliations

  • Kazuhiro Yoshiuchi
    • 1
  1. 1.The University of TokyoDepartment of Stress Sciences & Psychosomatic Medicine, Graduate School of MedicineBunkyo-kuJapan