I was diagnosed with PF last year, and no steroid creams worked. Before being diagnosed, two dermatologists couldn't tell me what was wrong. My primary care doctor suggested it might me autoimmune and told me to have a biopsy done.
I had the good fortune of being led to Dr. Anhalt at Johns Hopkins Dermatology. He prescribed the drug Rituxan via IV and it cured me! No side effects! I owe him my life. I am of Iranian descent, and apparently this is often seen in that region.