Fibromyalgia (FM) is a chronic condition that does not limit itself to just one area but rather, it manifests as a generalized, whole body condition where basically, everything hurts. The diagnosis is typically made by exclusion or by eliminating all other possible conditions as there is no single blood test for FM and unless other conditions that are test sensitive are present at the same time, most tests come back negative. Of course, this leaves the FM patient upset because, "….no one can figure out what’s wrong with me." We all seem to want a test to prove what we have is "real."
Unfortunately, in the real world, no blood test, x-ray, or exam procedure is 100% accurate (sensitive and specific), so even when tests return positive, there can be "false positives" that are caused by many things such as drug-induced test alterations and/or other conditions that alter the same test. On the other hand, there are "false negatives," so even though the test came back negative, it’s still possible that the problem one is present but the test may just not be sensitive (accurate) enough to detect it. FM is one of those conditions where only after a myriad of tests have been run and come back negative, can the diagnosis of FM be made with some degree of confidence.
Essentially, we have to prove that you don’t have something else causing similar symptoms before we can confidently (or at lease more confidently) diagnose you with fibromyalgia. To complicate this further, in "secondary FM," the cause of FM is known and is due to an underlying condition such as rheumatoid arthritis, lupus, hypothyroid, HIV, cancer, or a physical trauma such as a car accident or a work injury. When an accident is involved, the symptoms may be more confined to one area (then called "regional FM") making the diagnosis even more challenging as the classic 11 of 18 tender points may not hold up in these cases.
Finally, there are doctors out there that simply don’t "believe in" the condition and may say to the FM patient, "…there is no such thing, it’s all in your head. You simply have learn how to live with it. There’s nothing that can be done." Well, they actually may be partially right – that is, the "…it’s all in your head" part (don’t get mad… just wait!). Another finding that is well-published in peer review literature is the concept called central and peripheral "sensitization." This occurs when increased incoming sensory information from injured skin, muscles, and/or organs "bombard" areas in the central nervous system (spinal cord and brain) leaving it "sensitized" or more sensitive to "normal" incoming information. This is because the threshold or tolerance to normal incoming sensory stimuli is reduced and results in increased muscle pain commonly described by patients with FM.
To better illustrate this, hypersensitivity or central sensitization has been observed in people following a whiplash injury. One study recruited 14 whiplash patients and 14 "normals" to compare their responses when stimulating the leg (the non-injured area) as well as the neck (the injured area). Theoretically, if central sensitization didn’t exist, the responses to the exact same stimulus on the healthy leg of both the whiplash patients and the normal subjects would be equal. Instead, the researchers found the whiplash patients had significantly lower pain thresholds for 2 of 3 tests (a single electrical stimulus in the muscle, repeated electrical stimulation in the muscle and on the skin, but not from heat when applied to the skin). Each pain threshold was measured at the neck and leg before and after local anesthesia was applied to the painful, sore neck muscles. In the whiplash cases, a lower pain threshold was observed when the researchers stimulated both the skin and muscles at the healthy leg and at the injured anesthetized neck. That proves that the central nervous system has a "pain memory" which lowers the threshold so the whiplash patients feel pain more intensely and quicker than the non-injured people. This can help patients understand the answer to the question, "…why won’t this pain go away?" This pain memory or hypersensitization is similarly found in FM patients.
