Jan. 26, 2012 -- Extensive study of people suffering from Morgellons disease -- including analysis of their mysterious "skin fibers" -- finds no underlying cause of the illness.

Morgellons symptoms are as creepy as the name implies. Patients report slow-to-heal sores that often feel like bugs are crawling under their skin. They often scratch themselves raw. And they also report that mysterious colored fibers, granules,worms,eggs, fuzzballs, or other stuff comes out of their skin.

The CDC study was launched in 2008 at the request of California Sen. Dianne Feinstein because of a rash of Morgellons reports in that state.

The findings do not rule out the possibility that Morgellons is a newly recognized disease, note CDC researcher Michele L. Pearson, MD, and colleagues in the online journal PLoS One.

But after performing detailed examinations of patients, running blood and urine tests, analyzing skin biopsies and "fiber" particles, conducting psychological examinations, and looking for disease clusters, the researchers could not find any common cause of illness among Morgellons patients.

They suggest that the patients' symptoms and histories are similar to those of patients with a psychiatric condition called delusional infestation -- the delusional belief that one is infested with parasites.

More broadly, the findings suggest that Morgellons disease may result from the downward mind/body spiral known as somatization or somatoform disorder. In these conditions, physical symptoms worsen underlying anxiety or mood disorders, which then worsens the physical symptoms.