Common Fibromyalgia Misdiagnoses

Fibromyalgia is notoriously difficult to diagnose, even though it affects about 10 million Americans. The National Fibromyalgia Association (NFA) describes it as a complex chronic pain disorder. Unfortunately, there are currently no clinical tests to diagnose the condition and the NFA reports that it may take as long as five years for a patient to get a formal diagnosis.

The most common symptoms of fibromyalgia are pain, stiffness, fatigue, and weakness. For now, the only way your doctor can tell if you have this health problem is through your own list of symptoms, your medical history, a physical examination, and assessment of tender points on your body. According to the NFA, the criteria for determining if you have fibromyalgia are:

  • Widespread pain in all four quadrants of your body for at least three months.
  • Pain or tenderness in no less than 11 of the 18 specified tender points when pressure is applied.

Part of the difficulty in determining if a person has fibromyalgia is that other illnesses share some of the same symptoms. These include:

Rheumatoid Arthritis

This autoimmune condition causes inflammation or swelling, stiffness, and pain in multiple joints in the body. It can also cause fatigue and weakness. In advanced stages, rheumatoid arthritis can also affect internal organs.

How to tell the difference: Rheumatoid arthritis can be determined through a series of blood tests that check for chemical indicators of the disease, such as tumor necrosis factor, anti-cyclic citrullinated peptide, and C-reactive protein.

Lyme Disease

A chronic disease caused by bacteria transmitted by ticks. The symptoms include muscle and joint pain, fatigue, fever, chills, swollen lymph nodes, and in extreme cases arthritis symptoms, skin rashes, heart palpitations, and weakness.

How to tell the difference: Lyme disease can usually be diagnosed correctly through assessing the physical symptoms and your risk of being exposed to the ticks that cause the disease. However, the University of Maryland Medical Center states that a delayed diagnosis may incorrectly point to fibromyalgia. Blood tests aren't reliable if you're taking antibiotics, but they are usually better at identifying the bacteria as the infection progresses.

Multiple Sclerosis

This autoimmune disease occurs when inflammation damages the protective myelin sheath covering nerves, resulting in multiple scars or sclerosis. Some of the symptoms such as pain, fatigue, weakness, and inflammation mirror those of fibromyalgia.

How to tell the difference: Multiple sclerosis can be diagnosed through an MRI (magnetic resonance imaging) test, neurological exams, an electrical nerve test (called evoked potential test), and a spinal fluid test. They will look for scar tissues or nerve damage in the brain, spine, or optic nerves, and will try to confirm that they are not caused by any other health problems.

Multiple Chemical Sensitivity

This condition, caused by exposure to chemicals, can result in symptoms such as muscle and joint pain, chronic fatigue or lethargy, poor memory and concentration, and headaches or migraines—all symptoms of fibromyalgia as well.

How to tell the difference: Usually multiple chemical sensitivity can be determined if your symptoms improve when you're no longer exposed to a certain chemical (or chemicals). Or, your symptoms become worse when you're in contact with the chemical, even at lower levels than you're used to. Symptoms also affect multiple organs in your body.

Most of the similar illnesses to fibromyalgia—and fibromyalgia itself—are chronic conditions. They require special medical attention, and usually earlier diagnosis and treatment will improve your long-term health. See your doctor if you are experiencing any unusual persistent symptoms such as pain, fatigue, weakness, or memory problems.




National Fibromyalgia Association, University of Maryland Medical Center, National Institute of Arthritis and Musculoskeletal and Skin Diseases, Environmental Illness Resource, Arthritis Foundation