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Chronic Multisymptom Illness (CMI) (formerly known as Medically Unexplained Symptoms (MUS))


Medically Unexplained Symptoms (MUS), Medically Unexplained Physical Symptoms (MUPS) or Unexplained Symptoms are the terms used to describe symptoms that remain unexplained after an appropriate medical assessment that includes focused diagnostic testing. Patients are often given multiple labels that lack a well-defined disease explanation. Usual clinical features include a relative lack of objective signs and a chronic symptom course often marked by exacerbations, remissions, and recurrences. Therefore, clinical management must be based largely upon patient report, rather than specific findings on clinical examination or diagnostic testing. A compassionate approach to patients with medically unexplained symptoms (MUS) is essential.

In 2002 the Veterans Administration (VA) and the Department of Defense (DoD) developed the VA/DoD Clinical Practice Guideline for Management of Medically Unexplained Symptoms (MUS): Chronic Pain and Fatigue, which was designed to assist clinicians in primary care settings in all aspects of patient care related to medically unexplained symptoms involving chronic pain and fatigue.

According to the Institute of Medicine (IOM) Report: Gulf War and Health Volume 9: Treatment for Chronic Multisymptom Illness, 2013 about one-third of the 1991 Gulf War veterans suffer from an array of long-term medically unexplained symptoms known as chronic multisymptom illness (CMI). CMI is defined in the report as: "The presence of a spectrum of chronic symptoms experienced for 6 months or longer in at least two of six categories - fatigue, mood and cognition, musculoskeletal, gastrointestinal, respiratory, and neurologic - that may overlap with but are not fully explained by known syndromes (such as irritable bowel syndrome, chronic fatigue syndrome, and fibromyalgia) or other diagnoses." In addition, the report indicates that many symptoms reported by Iraq and Afghanistan war veterans overlap with symptoms experienced by 1991 Gulf War veterans. The report contains a comprehensive review and evalution of treatments for CMI.

In 2014, the VA/DoD MUS Clinical Practice Guideline was updated and renamed the VA/DoD Clinical Practice Guideline for the Management of Chronic Multisymptom Illness.

Table of Contents

Clinical Guidance

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Implementation Guidelines

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Implementation Tools

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Other Related Information

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Education and Training

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