The process of diagnosing fibromyalgia has been undergoing some changes in the past few years as more is learned about the illness. Currently there are two clinical fibromyalgia diagnostic criteria being used by health care providers: (1) the 1990 ACR Fibromyalgia Diagnostic Criteria, and (2) the 2010 ACR Preliminary Fibromyalgia Diagnostic Criteria.
The process of diagnosing fibromyalgia has been undergoing some changes in the past few years as more is learned about the illness.
Currently there are two clinical fibromyalgia diagnostic criteria being used by health care providers: (1) the 1990 ACR Fibromyalgia Diagnostic Criteria, and (2) the 2010 ACR Preliminary Fibromyalgia Diagnostic Criteria.
There is also a new diagnostic blood test for fibromyalgia, introduced in 2013, that is gaining credibility.
1990 ACR Fibromyalgia Diagnostic Criteria
In 1990, the American College of Rheumatology published the first diagnostic research criteria for fibromyalgia. According to that criteria, for a diagnosis of fibromyalgia, both of the following must be present:
- A history of widespread pain in all four quadrants of the body for a minimum duration of three months, and
- Pain in at least 11 of 18 designated tender points when four kilograms (about 10 pounds) of pressure are applied.
2010 ACR Preliminary Fibromyalgia Diagnostic Criteria
In 2010, the American College of Rheumatology developed a new set of diagnostic criteria which takes into account common FM symptoms, such as fatigue, sleep disturbances, and cognitive problems, as well as pain.
The new diagnostic criteria still requires the first part of the old criteria – a history of widespread pain in all four quadrants of the body for a minimum duration of three months – but will replace the second part, the tender point exam, with:
- A widespread pain index score which will be determined by counting the number of areas on the body where the patient has felt pain in the last week. The checklist includes 19 specified areas.
- A symptom severity score which is made up of two parts:
- From zero to nine points is calculated by rating the severity of three common symptoms – fatigue, waking unrefreshed and cognitive symptoms – on a scale of zero to three (three being the most pervasive).
- An additional three points can be added to account for the extent of additional symptoms such as numbness, dizziness, nausea, irritable bowel syndrome or depression. The final score is between 0 and 12.
A patient satisfies diagnostic criteria for fibromyalgia if the following 3 conditions are met:
- Widespread pain index (WPI) ≥7 and symptom severity (SS) scale score ≥5 or WPI 3 – 6 and SS scale score ≥9.
- Symptoms have been present at a similar level for at least 3 months.
- The patient does not have a disorder that would otherwise explain the pain.
You can download a copy of the New Clinical Fibromyalgia Diagnostic Criteria here.
Fibromyalgia Diagnostic Blood Test
In 2013, EpiGenetics introduced the FM/a® blood test, which they say is the first objective test to diagnose fibromyalgia via a simple blood test. According to the developers, “FM/a is a multi-biomarker-based test which concerns immune system white blood chemokine and cytokine patterns. Patients with fibromyalgia have a significantly dysregulated pattern regarding these proteins.”
Their studies show that the FM/a test is more than 93 % sensitive, a sensitivity comparable to the HIV blood test. (By comparison the rheumatoid arthritis blood test is only 65 percent sensitive.) It should be noted that no medical test is 100% accurate.
The FM/a blood test seems to be gaining credibility since it is being used in an NIH-funded study to differentiate FM patients from control patients.
The FM/a blood test is only available upon the order of a licensed physician. Because it is so new, it may not yet be covered by insurance plans.