The problem with DOP
DOP is Delusions of Parasitosis (the irrational belief that one is infected with parasites). People who think they have a condition called "Morgellons" sooner or later get an diagnosis of DOP.
This has led to a tendency to equate Morgellons with DOP. I think this tendency is not helping, for a variety of reasons.
Firstly, not all Morgellons sufferers claim to have parasites. Many claim that it's complication of Lyme disease, or other bacterial infection. Some claim a virus, some claim a depressed immune system for a variety of reasons, some quite outlandish (chemtrails, biowarfare, etc.)
The common elements of a "Morgellons" case are fairly simple:
1) Fibers found on the skin that are thought to be associated with their health problems.
2) Some Medically Unexplained Physical Symptoms
3) A belief in misdiagnosis by their physician.
The fibers are generally real objects, although sometimes the patient reports fibers that jump in and out of the skin, and even fly around the room. However most "fibers" are real, and generally resolve to lint, hair or sebum excretions.
Medically Unexplained Physical Symptoms (MUPS) is nothing new to the medical world, and treatment of MUPS has always been a problem. One thing that complicates MUPS is when a patient becomes "difficult", and begins to self-diagnose in an irrational manner. If the MUPS is suggested to have some somatic or psychological component, the the patient is often very resistant to any kind of psychotheraputic treatment, as they tend to vehemently reject any connection between their mental state or lifestyle and their physical ailments.
Which brings us back to DOP - if the tendency is there to equate Morgellons with DOP, then the patient is far more likely to enter into a diagnostic dialog in a highly distrustful and defensive state of mind. Their conviction in their own self-diagnosis will only become stronger as they mentally reject and retreat from the possibility of a somatic component, or any kind of delusion.
Thus, although it is tempting to equate Morgellons with DOP, it is both incorrect and potentially harmful. Diagnosis of DOP should be reserved for specific cases where an irrational belief in parasites is present. Other cases self-diagnosed as Morgellons would better be described as MUPS, as this is a more accurate description, and less polarizing for both patient and physician.