What is my long-term outlook based on Type?

The long-term prognosis for PRP is not set in stone. However, there are some guidelines that dermatologists feel comfortable in treating as Gospel. Suffice it to say that there has been insufficient research to be able to predict with any precision, when a PRP journey will end. 

In March 2003, Dr. Andrew Griffiths delivered a “Dowling Oration” to members of the British Association of Dermatology assembled in Liverpool, England. Dr. Griffiths reflected on 35 years of diagnosing, treating and researching pityriasis rubra pilaris. He unilaterally set the PRP prevalence rate at one in 400,000. The following patient populations reflect September 2021 population estimates.

  • European Union: 1,115
  • United States: 830
  • United Kingdom: 167
  • Canada: 94
  • Australia: 63

While the methodology used by Dr. Griffiths is subject to debate, dermatologists worldwide have accepted his estimates.

Adult Onset PRP

The PRP Global Database currently tracks
over 1,400 “Adult Onset” PRP patients

Type 1 — Classical Adult Onset PRP

  • Odds: One in 800,000
  • Patient population percentage: 55%
  • Estimated number of “active” Type 1 cases of PRP in US: 457; EU: 1,115
  • Prognosis: 80% of the ‘active” patients will have “spontaneous” remission within two to four years
  • After remission, relapses are uncommon

Type 2 — Atypical Adult Onset PRP

  • Odds: One in 8 million
  • Patient population percentage: 5%
  • Estimated number of “active” Type 2 cases of PRP in US: 42; EU: 56
  • Prognosis: estimated duration: 20 years or more.
Juvenile Onset PRP

The PRP Global Database currently tracks
over 300 “Juvenile Onset” PRP patients

Type 3 — Classical Juvenile Onset PRP

  • Odds: One in 4 million
  • Patient population percentage: 10%
  • Number of “active” Type 3 cases of PRP in US: 83; EU: 111
  • Usually occurs between the ages of 5 and 10
  • Prognosis: the average Type 3 remission is within one year

Type 4 — Circumscribed Juvenile Onset PRP

  • Odds: One in 1.6 million
  • Patient population percentage: 25%
  • Occurs in children before puberty
  • Number of “active” Type 4 cases of PRP in US: 206; EU: 279
  • Prognosis: Long term outcome unclear but possible improvement in late teens. Not considered a long-term affliction

Type 5 — Atypical Juvenile

  • Odds: one in 8 million
  • Patient population percentage: 5%
  • Number of “active” Type 5 cases of PRP in US: 42; EU: 56
  • Prognosis: long term, chronic
Other Onset PRP

Type 6 — HIV-Associated PRP

  • Odds: statistically insignificant (unless you have been diagnosed with Type 6). Inclusion of a Type 6 is the subject of debate and was not included in Griffith’s list of five.
  • Disease tends to be resistant to standard therapies
  • No further timeframe is suggested