Fibromyalgia Diagnosis

Diagnosis of fibromyalgia can be extremely difficult due to the fact that symptoms of fibromyalgia often mimic the symptoms of many other conditions, such as multiple sclerosis, certain cancers, chronic fatigue syndrome and autoimmune conditions. It often takes years for fibromyalgia to be diagnosed, and many people are misdiagnosed in the meantime.


Unfortunately, there are no specific tests that can definitively diagnose fibromyalgia. Fibromyalgia is diagnosed when other conditions have been ruled out, thus tests that can help with the diagnosis of fibromyalgia are usually tests that exclude other illnesses. Some of the more common tests that people may undergo include:

Complete blood count (CBC)
This simple blood test can rule out many conditions such as anemia, infection and even some cancers that may cause symptoms similar to fibromyalgia.
Rheumatoid factor
This blood test is used to rule out rheumatoid arthritis, which can cause widespread pain in the joints and other symptoms.
ANA (antinuclear antibody)
This blood test is used to screen for autoimmune diseases such as Lupus, which can cause symptoms such as fatigue, rash, arthritis and other symptoms similar to fibromyalgia.
ESR (erythrocyte sedimentation rate)
This blood test is another non-specific marker of inflammation; it may be elevated in autoimmune problems such as arthritis and lupus.
Thyroid tests
TSH measures thyroid stimulating hormone and can determine whether the thyroid gland is over or under producing. Fatigue is very common in hypothyroidism, thus a TSH level can rule out this condition, which can mimic fibromyalgia.
x-rays can help to rule out conditions such as arthritis, osteoporosis, scoliosis and ankylosing spondylitis, a form of arthritis which affects the sacroiliac joints and the spine. Many conditions affecting the bones can cause widespread pain, similar to the pain experienced in fibromyalgia.
MRI’s can be used to rule out conditions such as multiple sclerosis, which can cause many of the symptoms of fibromyalgia. MRIs may be ordered of the brain or spinal cord to rule out conditions that may cause headaches or the cognitive symptoms associated with fibromyalgia. Other areas of the body in which pain occurs may also be imaged.

Diagnostic Criteria

The American College of Rheumatology has set forth certain criteria that experts feel should be met in order to be diagnosed with fibromyalgia. Some experts disagree with the criteria, believing that the criteria are too restrictive and may miss some people who actually have fibromyalgia. The criteria are:

  • Widespread pain that has been present at least 3 months and occurs in all 4 quadrants of the body (above and below the waist and on both the right and left sides of the body)
  • 11 out of 18 identified tender points; pain is elicited on palpation of the tender points

Positive findings of widespread pain of long duration and tenderness on palpation of tender points as above, coupled with negative findings of disease on any other diagnostic test performed, makes the diagnosis of fibromyalgia more certain.

Diagnosis should be made by a physician familiar with fibromyalgia and its findings.

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Did You Know?

Fibromyalgia is a prevalent condition that affects many people in the United States. Approximately 3.7 million Americans have Fibromyalgia. That is 1 in every 73 people.

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