Delusional Parasitosis and Factitious Dermatitis   Delusional parasitosis and factitious disorder are psychiatric illnesses that are often encountered by clinicians. The differential diagnosis can be tricky, but treatment, which may include referral to a mental health specialist, may be trickier. Persons with delusional parasitosis falsely believe that they are infested with parasites and may experience formication, a hallucinatory crawling sensation on the skin that they attribute … [Read more...]