Medically Unexplained Symptoms

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Key points

  • Medically unexplained symptoms (MUS) are a significant cause of morbidity for patients and of resource use for the health care system.

  • Multiple diagnostic categories exist for patients with MUS.

  • Risk factors for MUS include female gender, low socioeconomic status, and a history of trauma (specifically childhood sexual abuse).

  • A careful history and physical examination is required for all patients with MUS, with additional diagnostic testing dictated by the patient’s symptom severity and chronicity.

Case 1: Ms D

Ms D is a 71-year-old woman with a history of peptic ulcer disease, metabolic syndrome, major depressive disorder, and osteoarthritis who presents for clinical follow-up with pain all over her body. She states that she cannot remember a time when her entire body did not hurt. She is also concerned about chronic abdominal pain.

On examination, her vital signs are within normal limits. She is tender to light palpation in every major muscle group. She is diffusely tender to light palpation on

Definitions

The terms MUS and somatization refer to symptoms that have minimal or no apparent basis in physical disease. These terms can also apply to patients with underlying disease explaining the presence of physical symptoms, but with a symptom burden out of proportion to what is expected. Some investigators criticize the use of the term MUS because of the ambiguity inherent in declaring a symptom to be unexplained, or unexplainable, and the importance of including diseases that may have psychological

Pathophysiology

The pathophysiology of MUS is poorly understood. Controversy exists as to whether the syndrome is predominantly physical or psychiatric, or a combination of the two, and whether the various named syndromes within the broader category of MUS or functional somatic syndromes are physiologically distinct, valid, and meaningful.12, 13 In one small study, 1 in 3 physicians thought that the cause of MUS was likely spiritual.14 Some evidence suggests a familial risk for somatization, although it

Symptoms

The most common symptom attributed to MUS is pain,1 including diffuse myalgias, arthralgias, low back pain, headache, and dysuria. Other possible symptoms include:

  • Systemic symptoms: fatigue and insomnia

  • Head and neck symptoms: tinnitus, pseudo–eustachian tube dysfunction, atypical facial pain, globus sensation27

  • Cardiac symptoms: chest pain, palpitations, and dyspnea

  • Gastrointestinal symptoms: bloating, nausea, abdominal discomfort, constipation, and diarrhea

  • Genitourinary symptoms: chronic pelvic

Case 2: Ms L

Ms L is a 47-year-old woman with a history of hepatitis C and generalized anxiety disorder who presents with hemifacial pain and seizures. She states that she experiences episodes of throbbing pain that are migratory, occurring all over her scalp, lasting hours to days. It seems to occur more frequently when she has to leave the house to take her children to school or to come to medical appointments. No photophobia or phonophobia. No fevers, chills, or night sweats. No weight loss or nausea.

Diagnostic testing/imaging studies

A diagnosis of MUS can be made only after organic disease has been ruled out. It is therefore critical for clinicians to take a careful history and perform a thorough physical examination before making a diagnosis of MUS. History taking should be broad and comprehensive, with a specific focus on other symptoms that may suggest organic disease, and on patient attribution (to what does the patient attribute the symptoms?). The social history can be particularly useful in this setting as well,

Differential diagnosis

Somatization and major depressive disorder commonly coexist: 50% of patients with major depression present with MUS and between 45% and 95% of patients with major depression present with only somatic symptoms at the time of diagnosis.32 Depressed patients who lack a consistent primary care relationship are more likely to present with exclusively somatic symptoms.32 In addition, the severity of depression symptoms and decreased quality of life ratings are correlated with the presence of painful

Case 3: Mr C

Mr C is a 55-year-old man with a history of tobacco use, physical and sexual abuse in childhood, and Reinke edema. He presents to clinic for routine follow-up of postnasal drip, hoarseness, and a sensation that he needs to keep clearing his throat. He has had these symptoms for 2 years but only recently obtained health insurance, so presents to you for primary care follow-up. Five years before today’s visit, he underwent direct laryngoscopy, which showed polypoid degeneration of the true vocal

Management

Patients with MUS are highly variable with regard to their level of insight, focus of attention, and needs from medical providers35 and may provide cues to their providers regarding their need for emotional support or explanation for their symptoms.36 It can be particularly challenging for providers to discuss a diagnosis such as MUS, or one of its specific variants, with patients. The patient's experience is subjective, and the lack of objective evidence of organic disorder should not minimize

Future considerations/summary

In summary, caring for patients with MUS is challenging for health care providers. Even defining somatization syndromes is complex and controversial, reflecting the medical community’s limited understanding of the pathophysiology for this group of disorders. Although risk factors for MUS have been described and are well understood, little is known about how MUS can be prevented. Uncertainty in medicine, as in any human enterprise, is a given, but the difficulties in identification and treatment

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References (55)

  • J. Reid et al.

    Pilgrimage of pain: the illness experiences of women with repetition strain injury and the search for credibility

    Soc Sci Med

    (1991)
  • V. De Gucht et al.

    Personality and affect as determinants of medically unexplained symptoms in primary care; a follow-up study

    J Psychosom Res

    (2004)
  • K.M. Rost et al.

    The comorbidity of DSM-III-R personality disorders in somatization disorder

    Gen Hosp Psychiatry

    (1992)
  • S.R. Hahn et al.

    The difficult doctor-patient relationship: somatization, personality and psychopathology

    J Clin Epidemiol

    (1994)
  • E.A. Walker et al.

    Predictors of physician frustration in the care of patients with rheumatological complaints

    Gen Hosp Psychiatry

    (1997)
  • A.J. Barsky et al.

    Somatization increases medical utilization and costs independent of psychiatric and medical comorbidity

    Arch Gen Psychiatry

    (2005)
  • K. Kroenke et al.

    Gender differences in the reporting of physical and somatoform symptoms

    Psychosom Med

    (1998)
  • F. deGruy et al.

    Somatization disorder in a family practice

    J Fam Pract

    (1987)
  • J. Bailer et al.

    Evidence for overlap between idiopathic environmental intolerance and somatoform disorders

    Psychosom Med

    (2005)
  • G. Lange et al.

    Cognitive functioning in Gulf War illness

    J Clin Exp Neuropsychol

    (2001)
  • B.N. Smith et al.

    Gulf war illness: symptomatology among veterans 10 years after deployment

    J Occup Environ Med

    (2013)
  • American Psychiatric Association

    Diagnostic and statistical manual of mental disorders

    (2013)
  • S. Wessely et al.

    There is only one functional somatic syndrome

    Br J Psychiatry

    (2004)
  • J.H. Shin et al.

    A spiritual problem? Primary care physicians' and psychiatrists' interpretations of medically unexplained symptoms

    J Gen Intern Med

    (2013)
  • A.K. Mattila et al.

    Alexithymia and somatization in general population

    Psychosom Med

    (2008)
  • E.A. Walker et al.

    Medical and psychiatric symptoms in women with childhood sexual abuse

    Psychosom Med

    (1992)
  • M.L. Paras et al.

    Sexual abuse and lifetime diagnosis of somatic disorders: a systematic review and meta-analysis

    JAMA

    (2009)
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