Joined: 09 Feb 2006
|Posted: Wed Jan 30, 2008 12:40 am Post subject: Morgellons in the news today
What's Up Doc? When is a condition a new disease?
By Dr. Jeff Hersh/Daily News correspondent
Tue Jan 29, 2008, 02:29 PM EST
Q: I read a newspaper article that mentioned a new disease called Morgellons. I have never heard of this, what is it?
A: When a new disease is suspected there is often controversy and confusion.
How is it diagnosed, especially if it is poorly understood?
How do we know it is a new disease and not just a different spectrum of symptoms from an existing disease?
A "new" disease may not be something that has just popped up. It may have been around for a while but never identified as a separate disease entity.
Many diseases are diagnosed based on clinical symptoms and the patient's history. For these clinical diagnoses, certain tests may help "clinch" the diagnosis, even though the test itself is not sufficient to make the diagnosis. For example, many autoimmune diseases (such as lupus) are diagnosed based on clinical criteria and positive results of certain "indicator" blood tests. A positive "indicator" test means it is more likely that the patient has the disease. However, an "indicator" test can be positive even though the person does not have the disease, and it can be negative even in people who do have the disease. So although an "indicator" test is helpful, it does not make the diagnosis, and a negative test does not rule out the diagnosis.
Once a disease is better understood, tests may be developed to rule in or rule out the diagnosis, even though no test is perfect. For example, with our increased understanding of AIDS over the last several decades, we now have tests that, when done over time, can help rule in or rule out whether a person is infected with the HIV virus.
With even better understanding of a disease it is possible that screening tests can be developed to diagnose the disease early, even before symptoms arise. Screening tests can help people begin treatment early, improving outcomes. PAP smears, mammograms and colonoscopies are examples of screening tests for cancers that fit this description.
The lack of a definitive test makes it much more difficult to study a disease. It is possible that people being studied do not have the disease in question, but have similar symptoms for some other reason. It also means that people with the disease who have atypical symptoms may not be studied.
Morgellons disease manifests with symptoms that include a crawling/biting insect-like sensation that feels like it is under the skin, called formication. There is also a rash (maybe from the condition or maybe from the patient picking at their skin because of the crawling sensation) and often fiber-like filaments on or under the skin. Some patients get systemic symptoms such as joint and/or muscle aches, fatigue and even concentration difficulties.
As you can see from this description, the symptoms of Morgellons are non-specific. In fact, formication can occur with menopause, diabetes, as a reaction to many different medications as well as from other causes. This makes the diagnosis of Morgellons even more challenging.
The fiber-like strands from Morgellons patients have been analyzed, although without definitive conclusions. Mark Boese at an FBI lab found that the fibers were "consistent with something that the body may be producing."
Early Morgellons research noted a possible association with Lyme disease, and yet other research questions a connection with infection from Agrobacterium, a genus of bacteria used that causes tumors in plants.
Morgellons disease emerged as a concern and was named by biologist Mary Leitao who noted many of the symptoms above in her 2-year-old son. As is often the case, once a new disease is suspected, reports of a similar spectrum of symptoms may be found in old medical literature. European physicians may have first noted patients with symptoms similar to Morgellons in the 1600s.
Morgellons shares some of its key symptoms with a condition called delusional parasitosis (DP). Patients with this condition have formication symptoms and can develop skin lesions from their scratching, although the symptoms in DP are felt to be psychiatrically based and not from a physical condition. Because of this, some physicians question whether Morgellons really is a new disease. On the other hand, some physicians wonder how many patients have been diagnosed with DP who actually had Morgellons.
With all this said, the Centers for Disease Control and Prevention have enlisted the aid of the U.S. Armed Forces Institute of Pathology and the American Academy of Dermatology to research Morgellons. Hopes are to shed some light on its underlying cause, clarify ways to make the diagnosis and to look for possible treatments. For now, this perplexing condition remains a medical mystery.
Jeff Hersh, Ph.D., M.D., F.A.A.P., F.A.C.P., F.A.A.E.P., can be reached at DrHersh@juno.com.