Q: I have read that Lyme disease is highly treatable with antibiotics. I was diagnosed with Lyme disease three years ago, yet despite several rounds of antibiotics, I still suffer from muscle aches and fatigue on a daily basis. Why isn't the treatment helping me?

A: Without personally examining you or evaluating your medical records, I can only suspect one of two things: You have a stubborn case of Lyme disease that isn't responding to standard treatment; or, more likely, you don't have Lyme disease at all. Lyme disease and fibromyalgia are sometimes confused, even by doctors performing tests. Recent research has confirmed this fibromyalgia-lyme disease confusion.

As many as half of the people who believe they have Lyme disease – even those in whom Lyme was diagnosed by their doctors – probably don't have the disease. The reason for misdiagnosis, in large part, is that blood tests used to diagnose Lyme disease are prone to false positives. Relying on results of the blood test alone can lead you and your doctor to believe you have a disease that you really don't have. 

In fact, in a 1993 study of 788 patients referred to a university Lyme disease clinic, researchers found that 452 – more than half – of those people did not have, and had probably never had, Lyme disease at all. Their diagnosis, instead, was fibromyalgia or a similar condition called chronic fatigue syndrome (CFS). An additional 156 patients, who had experienced Lyme disease in the past (which, in fact, might have been cured by the antibiotics), currently had fibromyalgia or CFS. Active Lyme disease was found in only 180 – or 23 percent – of the patients.

Because of the potential for misdiagnosis, most doctors rely on several factors in addition to blood tests to diagnose the disease. These include: the probability of exposure to disease-carrying ticks; your medical history; your symptoms; and physical examination results. 

Lyme disease generally begins with a localized circular red rash where the bacterium from the infection-bearing tick enters the skin. Later symptoms, occurring after the infection has spread, can include joint pain and swelling, heart inflammation, and nerve involvement with associated muscle pain and fatigue. 

Some of these symptoms are similar to those of other forms of arthritis and even to unrelated diseases. For example, muscle pain and fatigue are also common in fibromyalgia. Your physician should be knowledgeable about Lyme disease and know what criteria are necessary for its diagnosis.

Unlike Lyme disease, fibromyalgia, CFS and other related conditions cannot be cured with antibiotics. Consequently, if a person has both fibromyalgia and a positive blood test for Lyme disease, antibiotics will probably not relieve all of the symptoms. If there is reasonable doubt that you actually have Lyme disease or if you haven't had characteristic symptoms of Lyme disease other than the positive blood test, your doctor will probably choose not to prescribe antibiotics again.

If you actually have fibromyalgia or something similar, your treatment will differ significantly. Fibromyalgia can be managed effectively through a number of measures, including exercise to promote muscle conditioning, medications to promote deep sleep, relaxation techniques and maintaining a positive attitude.

Discuss your concerns and these various issues with your doctor. He should be able to help you sort out the actual cause of your pain and fatigue – be it Lyme disease or something different – and prescribe an effective treatment plan for you.

Doyt Conn, MD, Rheumatologist