What Is Pityriasis Rubra Pilaris?
rubra pilaris (PRP) is a rare skin disorder that causes constant inflammation
and shedding of the skin. PRP can affect parts of your body or your entire
body. The disorder may begin in childhood or adulthood and affects males and
Types of PRP
are six types of PRP.
Classical Adult Onset
This is the most common type of
PRP, and it begins in adulthood. The symptoms usually go away after a few
years. In some rare cases, the symptoms come back later.
Atypical Adult Onset
This type also begins in adulthood,
but the symptoms may last for more than 20 years.
Classical Juvenile Onset
This form begins in childhood. The
symptoms usually go away within a year, but may return later.
Circumscribed Juvenile Onset
This type of PRP begins in children
before they reach puberty. It most commonly affects the palms of the hands,
soles of the feet, knees, and elbows. The symptoms may go away during teenage
Atypical Juvenile Onset
This form of PRP is sometimes
inherited. It’s present at birth or may develop during early childhood. The
symptoms often last indefinitely.
This form of PRP is associated with
HIV infection and is very difficult to treat.
What Causes PRP?
exact cause of PRP is unknown. PRP most commonly occurs spontaneously for no
identifiable reason. While some cases of PRP are inherited, most are not.
Inherited PRP tends to be more severe.
adult onset PRP may be associated with underlying skin cancer. However, the
rate of occurrence of skin cancer with classical adult onset PRP is unknown. If
you have classical onset PRP, have your doctor check you for skin cancer to be
According to the National Organization for Rare Disorders, early research suggests that PRP may occur due to an
abnormality in the way the body processes vitamin A. However, more research
needs to be conducted to determine if this is true. It’s also thought that PRP
is connected to an atypical immune system response, according to the Genetic and Rare Diseases Information Center (GARD).
How Is PRP Inherited?
can be inherited. You may inherit PRP if one of your parents passes down the
defective gene that causes the disorder. Your parent may be a carrier of the
defective gene, but not actually have the disorder. If one of your parents is a
carrier of the defective gene, there is a 50 percent chance that the gene will
be passed to you. However, you may not develop clinical PRP even if you inherit
the defective gene.
What Are the Symptoms of PRP?
causes pink, red, or orange-red scaly patches on your skin. The patches are
usually itchy. You may only have the scaly patches on parts of your body. The
scaly patches most often occur on the elbows, knees, hands, feet, and ankles.
The skin on the palms of your hands and the soles of your feet may also become
red and thickened. The scaly patches may eventually spread over your entire
How Is PRP Diagnosed?
PRP is often mistaken for other
more common skin conditions, such as psoriasis, or less common conditions, such
as lichen planus and pityriasis rosea. Psoriasis is characterized by itchy,
scaly patches typically red in color. However, unlike PRP, psoriasis can be
more easily and successfully treated. Sometimes, it’s not until the scaly
patches fail to respond to treatment that PRP is considered.
If your doctor suspects PRP, they
may perform a skin biopsy to make a diagnosis. A skin biopsy is a
medical procedure in which a small sample of skin is removed so that the doctor
(or a consulting pathologist) can examine it under a microscope.
What Are Possible Complications of PRP?
For the most part, PRP can be itchy and lead to discomfort,
which can decrease over time even if the rash looks like it’s getting worse.
Typically, there are few complications, but according to PRP Support Group, the rash can lead to other
conditions, such as ectropion. In this condition, the eyelid turns out,
exposing the surface of the eye. The condition can also cause problems with the
lining in the membrane of the mouth, leading to irritation and pain.
Over time, PRP can cause a condition called keratoderma in
which the skin on the hands and soles of the feet becomes very thick. Fissures,
or deep cracks in the skin can develop. Some people with PRP are sensitive to
light and have trouble sweating or regulating body temperature when it’s hot.
How Is PRP Treated?
is no cure for PRP. Treatment consists of relieving the symptoms that accompany
PRP. Your doctor may prescribe one or more of the following treatments to
- topical creams that contain urea or lactic acid
- oral vitamin A (effectively reduces or relieves symptoms in
one-third of patients, according to GARD)
- oral retinoids like isotretinoin or acitretin (retinoids are
medications that slow the growth and shedding of skin cells)
- biologics (medications that affect the immune system, such as
Humira, Enbrel, Remicade)
- ultraviolet light therapy, which is usually prescribed in
combination with Psoralen (a medication that makes you less sensitive to the
sun) and a retinoid
Can I Prevent PRP?
Because the cause
and onset of PRP are unknown, you cannot prevent this condition. Getting a
diagnosis and finding a treatment that works for you as soon as you show signs
and symptoms are key to a good outlook. This is especially important as it’s
possible to develop more than one type of PRP over the course of the disease.
Will PRP Go Away?
on the type of PRP you have, your symptoms may or may not go away. If you have
classical adult onset PRP (the most common form of the disorder), your symptoms
will most likely last a few years (or less) and then never return. Treatments
may make symptoms less noticeable.