Pityriasis rubra pilaris is a rare skin condition that causes reddish‑orange patches, thickened skin on the palms and soles, and rough bumps around hair follicles. People with pityriasis rubra pilaris may feel itch, burning, or tenderness, and doctors often see areas of normal skin “islands” within red plaques. It can start in childhood or adulthood, and the course varies, with some types clearing in a few years while others last longer. Pityriasis rubra pilaris is not life‑threatening, but severe flare‑ups can affect comfort, sleep, and daily activities. Treatment often includes moisturizers, topical steroids, vitamin A–like pills, and light therapy, and early symptoms of pityriasis rubra pilaris should be checked by a dermatologist.
Overview
Pityriasis rubra pilarisSymptoms
Early symptoms of pityriasis rubra pilaris include rough, reddish‑orange patches and bumps around hair follicles. Many develop thick, painful scaling on the palms and soles, with itch or burning, nail changes, and areas of normal skin scattered among inflamed plaques.
Outlook and prognosis
Most people with pityriasis rubra pilaris improve gradually over months to a few years, though the pace varies. Flares can happen and may affect comfort, mobility, and everyday routines, but treatment often eases redness, scaling, and thickened skin. Regular follow-up helps adjust care and protect skin health.
Causes and risk factors
Causes are largely unclear. Some cases run in families due to changes in the CARD14 gene; most are sporadic. Reported risk modifiers include HIV infection, recent infections or skin injury, and possibly immune dysregulation; lifestyle factors aren’t known contributors.
Genetic influences
Genetics play a limited, variable role in pityriasis rubra pilaris. Most cases are sporadic, but rare inherited forms exist, often linked to CARD14 gene changes, which can run in families in an autosomal dominant pattern. Genetic testing is uncommon.
Diagnosis
Doctors diagnose pityriasis rubra pilaris mainly by a skin exam, noting orange-red scaly patches, islands of sparing, and thick palms/soles. A skin biopsy often confirms the diagnosis of pityriasis rubra pilaris. Tests may rule out psoriasis or fungal infection.
Treatment and drugs
Pityriasis rubra pilaris is managed with skin-calming care and medicines that dial down inflammation. Dermatologists often use moisturizers, vitamin A–related pills (retinoids), and sometimes methotrexate or biologic injections. Light therapy or short courses of steroids may help flares.
Symptoms
Day to day, pityriasis rubra pilaris can show up as dry, scaly patches, rough bumps, and sore, thickened skin on the hands and feet. Many people first notice early symptoms of pityriasis rubra pilaris as sandpapery bumps on the arms or cheeks and heavy scalp flaking that looks like stubborn dandruff. Symptoms vary from person to person and can change over time. When larger areas become red and hot, the skin can feel tight and uncomfortable.
Flat or raised areas of reddish-orange skin that feel dry and flake. They can start in one area and spread over weeks. Clinicians call this plaques and scaling, which means thicker, flaky skin that can be tender or sore.
Tiny, rough bumps around hair follicles feel like sandpaper under your fingertips. They often show up on the upper arms, thighs, or cheeks. For many people with pityriasis rubra pilaris, these bumps are one of the first signs.
Skin on the hands and feet becomes thick, stiff, and yellowish. Deep, painful cracks can form, making walking or gripping objects hard. What once felt effortless can start to require more energy or focus.
Heavy, stubborn flakes on the scalp resemble severe dandruff. Hair may look thinner over time from inflammation and scratching. Hats or dark shirts can collect noticeable flakes.
How people usually first notice Pityriasis rubra pilaris?
Many first notice pityriasis rubra pilaris (PRP) when scattered, rough, sandpapery bumps appear around hair follicles on the elbows, knees, or hands, then spread and join into orange‑red patches with fine scaling. As the rash widens, the skin can feel tight or tender, palms and soles may thicken and crack (sometimes painful when walking), and “islands” of normal skin may stand out within the redness. People often seek care when the rash rapidly expands over weeks, itching or burning increases, or nail changes and thickened palms/soles start to interfere with daily activities—these are common first signs of PRP and how PRP is first noticed.
Types of Pityriasis rubra pilaris
Pityriasis rubra pilaris (PRP) has several recognized clinical variants that differ in age of onset, body areas involved, and how long symptoms last. Some start suddenly with widespread redness and scaling, while others remain more limited to the palms, soles, or scalp. Symptoms don’t always look the same for everyone. Knowing the main variants of PRP can help you and your clinician discuss types of PRP that match your pattern and guide treatment expectations.
Classic adult type
Often begins abruptly with red-orange patches that can spread and form areas of thicker skin. Palms and soles may become painful and thickened, and nails can become ridged.
Atypical adult type
Tends to run a longer, more chronic course with thicker plaques and scalp involvement. Hair changes and more prominent thickening may appear over time.
Classic juvenile type
Starts in childhood with widespread redness, scaling, and follicle-centered bumps. Many children improve over 1–3 years, though palms and soles can stay thick and sore during flares.
Circumscribed juvenile type
Mainly affects elbows, knees, and often the palms and soles with well-defined thick, scaly plaques. The rest of the skin is usually spared, and symptoms may come and go.
Atypical juvenile type
Usually long-lasting with thickened plaques, scalp scaling, and variable redness beginning early in life. Nail changes and palm–sole thickening are common.
HIV-associated type
Occurs in people living with HIV and can be more persistent or severe. It often needs coordinated care for skin symptoms alongside HIV treatment.
What genetics can tell you about symptoms
Some forms of pityriasis rubra pilaris (PRP) are linked to changes in the CARD14 gene, which can turn skin inflammation “on” too easily. This can lead to orange-red scaly patches, thickened palms and soles, and follicle-based bumps that feel rough.
Causes and risk factors
What causes pityriasis rubra pilaris is not fully understood, and it likely involves an immune imbalance. Rare family forms come from a change in the CARD14 gene, while most cases appear without a clear trigger. Some people notice it after an infection, and an atypical form can occur with HIV. Doctors distinguish between risk factors you can change and those you can’t. There are few modifiable risks, but caring for overall health and treating infections promptly is sensible.
Environmental and biological risk factors
Understanding what raises the chance of pityriasis rubra pilaris can help you know when to watch your skin more closely. Doctors often group risks into internal (biological) and external (environmental). These factors do not diagnose the condition, but they explain why it sometimes starts after illnesses or skin stress. Knowing them can prompt timely care if early symptoms of pityriasis rubra pilaris appear.
Pityriasis rubra pilaris is more likely to begin in childhood or in midlife (around 40–60 years). These age windows reflect shifts in skin and immune biology that can make onset more likely.
Changes in immune signaling and inflammation can set the stage for pityriasis rubra pilaris. Coexisting inflammatory conditions may tilt the balance toward a flare.
The condition sometimes starts after a respiratory or other infection. The immune response to infection can temporarily alter skin processes and trigger pityriasis rubra pilaris.
Pityriasis rubra pilaris is more common in people living with HIV, and a specific pattern is recognized in this setting. Immune changes related to HIV can raise risk.
Genetic risk factors
Most people diagnosed with Pityriasis rubra pilaris do not have an inherited cause; their condition appears without a known genetic change. In a minority, changes in a skin‑signaling gene called CARD14 can raise the chance of PRP and may run in families. Carrying a genetic change doesn’t guarantee the condition will appear. Genes alone cannot predict early symptoms of Pityriasis rubra pilaris or how severe it might become.
CARD14 variants: Changes in the CARD14 gene can over-activate signals that guide skin growth and inflammation. This raises the chance of PRP in many familial cases and in a small number of isolated cases.
Autosomal dominance: When PRP is inherited, a single altered copy of CARD14 can be enough to increase risk. Each child of an affected parent has a 50% chance of inheriting the change. Not everyone who inherits it develops PRP.
Variable expression: The same genetic change can lead to different ages of onset and skin findings, even within one family. Risk is not destiny—it varies widely between individuals. Some relatives may stay symptom-free, while others develop PRP at some point.
De novo changes: Sometimes a CARD14 change arises for the first time in a child and is not present in either parent. This can explain a single case of PRP in a family with no prior history. Parents in this situation usually have a low chance of having another child with the same change.
Juvenile familial type: Atypical juvenile PRP often has a genetic basis with CARD14 changes. Symptoms can begin in childhood and may persist for years. Other childhood PRP types are typically not inherited.
Psoriasis overlap: CARD14 changes are also seen in plaque psoriasis, so some families include members with either PRP or psoriasis. This overlap points to shared skin inflammation pathways. It does not mean PRP will turn into psoriasis or the other way around.
Family history: Having a close relative with PRP or a known CARD14 change raises genetic risk compared with the general population. However, many families with one affected person have no other relatives with the condition. Genetic counseling can help clarify patterns in a specific family.
Genetic testing: Testing for CARD14 may be considered when PRP starts in childhood, is atypical, or several relatives are affected. A positive result can confirm a hereditary form and guide family counseling. A negative result does not rule out PRP because many cases have no identifiable genetic change.
Other genes unknown: Research continues to look for additional genes that contribute to PRP. So far, consistent genetic causes beyond CARD14 have not been confirmed. Future studies may expand the list of known risk genes.
Lifestyle risk factors
Pityriasis rubra pilaris isn’t caused by lifestyle, but daily habits can influence symptom intensity, flares, and skin comfort. Understanding how lifestyle affects Pityriasis rubra pilaris can help you reduce triggers and support the skin barrier. The following focus on lifestyle risk factors for Pityriasis rubra pilaris and how they may worsen redness, scaling, itch, and cracking.
Diets high in ultra-processed, high-glycemic foods may amplify systemic inflammation and itch in PRP. Emphasizing whole foods and omega-3–rich options may help calm redness and support the skin barrier.
Alcohol can increase skin vasodilation and itch, making PRP redness and burning feel worse. Cutting back may also reduce dryness and stinging sensations.
Smoking promotes inflammation and impairs skin healing, which can aggravate PRP plaques and fissures. Quitting may lessen scaling and reduce painful cracking.
Psychological stress can heighten neuroimmune signaling that worsens PRP flares and itch. Regular stress-management practices may steady symptoms and reduce scratching urges.
Risk prevention
Pityriasis rubra pilaris isn’t fully understood, so there’s no sure way to prevent it from starting. Most prevention focuses on protecting skin, easing irritation, and catching problems early so flares are shorter and milder. Prevention is about lowering risk, not eliminating it completely. If you notice early symptoms of pityriasis rubra pilaris, getting prompt care may help reduce complications and discomfort.
Use a mild, fragrance‑free cleanser and lukewarm water, not hot. Skip scrubs or loofahs that can scratch and inflame skin. Pat dry and avoid rubbing.
Apply a thick, bland emollient right after bathing to seal in moisture. Keeping the skin barrier strong may lessen scaling and itch. Reapply to hands and feet during the day.
Use broad‑spectrum SPF 30+ and protective clothing to prevent sunburn, which can aggravate inflamed skin. Seek shade during peak sun hours. Reapply sunscreen every 2 hours when outdoors.
Choose fragrance‑free products and soft, breathable fabrics like cotton. Avoid wool, harsh detergents, and alcohol‑based gels that sting or dry the skin. Patch‑test new products on a small area first.
Transmission
Pityriasis rubra pilaris is not contagious; you can’t catch it or pass it on through touch, hugging, sharing towels, swimming pools, or the air. Most people with Pityriasis rubra pilaris are the only one in their family, so there’s no person-to-person transmission to worry about. Rarely, it can run in families, where an altered gene is passed from a parent to a child and may affect several generations. This genetic transmission of Pityriasis rubra pilaris is uncommon, and it can also appear for the first time in someone with no family history because of a new gene change.
When to test your genes
Pityriasis rubra pilaris isn’t typically caused by inherited mutations, so most people don’t need genetic testing. Testing may be helpful if symptoms begin in childhood, if several family members are affected, or if your dermatologist suspects a CARD14-related form. Ask about testing when results could change treatment, monitoring, or family counseling.
Diagnosis
Clues often appear on the skin—reddish‑orange patches, rough bumps around hair follicles, and thicker skin on the palms or soles—that prompt a closer look. Doctors usually begin with a careful skin exam and questions about your symptoms and health history. If features overlap with other rashes, small tests can help confirm the diagnosis of Pityriasis rubra pilaris. The goal is to identify the pattern and rule out close look‑alikes like psoriasis or eczema.
A dermatologist looks at the color, scale, and pattern across the body, including islands of normal skin among widespread redness. They also check nails, scalp, and the thickness on palms and soles, which can be clues.
Your provider asks when the rash started, how it changed over time, and whether new medicines, infections, or stress were present. Family history and how the rash affects daily activities also guide next steps.
A handheld magnifier helps visualize fine surface details such as follicle-centered bumps and scale patterns. This noninvasive exam can help distinguish PRP from psoriasis or eczema.
A tiny skin sample is taken under local anesthetic and examined under a microscope. The tissue pattern can support PRP when the clinical picture is unclear and help rule out other causes.
Stages of Pityriasis rubra pilaris
Pityriasis rubra pilaris does not have defined progression stages. It’s grouped into types rather than stages, and its course can vary—some people see a sudden spread that later settles, while others have more limited, persistent patches. Doctors typically diagnose it by examining the skin and medical history; early symptoms of pityriasis rubra pilaris may include rough, scaly bumps around hair follicles and orange‑red, flaky areas, sometimes with thickened skin on the palms and soles. A small skin sample (biopsy) can confirm the pattern under the microscope, and different tests may be suggested to help rule out other conditions that can look similar.
Outlook and prognosis
Looking at the long-term picture can be helpful. For many people with Pityriasis rubra pilaris (PRP), symptoms peak over months and then gradually settle. Many people find that symptoms improve over time, though the path can be uneven. Classic PRP often goes into remission within 3 to 5 years, while some types clear sooner and others linger or come and go. Early symptoms of Pityriasis rubra pilaris like rough follicular bumps, orange-red patches, and thickened palms or soles can disrupt sleep, work, and social life, but flares usually become less intense with steady care.
In medical terms, the long-term outlook is often shaped by both genetics and lifestyle. A small number of people have a genetic form that can persist, sometimes starting in childhood and returning in adulthood. Most people with PRP do not face life-threatening risks from the condition itself, but severe skin involvement can raise complications such as infections, dehydration, or problems with body temperature. Hospital care may be needed during widespread flares, especially if the skin becomes very inflamed or peels extensively. Mortality directly from PRP is rare today, particularly with modern dermatology care and infection prevention.
With ongoing care, many people maintain daily routines and gradually taper treatments as the skin calms. Systemic medicines, phototherapy, and targeted moisturizers can speed recovery and limit scarring or thickening. Talk with your doctor about what your personal outlook might look like, including how your specific PRP type, age, other health conditions, and response to treatment shape the timeline. Knowing what to expect can ease some of the worry and help you plan for work, travel, and follow-up visits.
Long-term effects
Day to day, long-standing skin changes from pityriasis rubra pilaris can affect comfort, mobility, and confidence. Long-term effects vary widely, with some people improving within a few years and others having a relapsing or persistent course. Doctors often track how redness, scaling, and thickened skin settle or flare over time, sometimes after the early symptoms of pityriasis rubra pilaris have shifted. Nail, hair, and eye surfaces may also be involved in ongoing ways.
Large areas can stay red or orange‑red with fine scaling. This may come and go or remain steady for months to years. For some, the skin becomes universally involved.
Skin on the hands and feet can grow thick, stiff, and waxy. Deep cracks may form and make walking or manual work painful. This is common in pityriasis rubra pilaris.
Ongoing itch can disrupt sleep and focus. Some feel a burning or tight sensation where the skin is inflamed. Scratching can worsen soreness.
Fissures can open on heels, fingertips, or around joints. These can bleed and make daily tasks difficult. They may also raise infection risk.
How is it to live with Pityriasis rubra pilaris?
Daily life with pityriasis rubra pilaris can feel unpredictable: skin may be red, scaly, and tender, with thickened palms and soles that make walking, typing, or gripping objects uncomfortable, and itching or burning that interrupts sleep. Many find clothing choices, bathing routines, and time outdoors revolve around comfort, sun protection, and gentle skin care, and flares can sap energy and mood. Work, school, and social plans may need flexibility for appointments and symptom days, while partners, family, and friends often help with practical tasks and emotional support. With the right care plan and patience, most people learn rhythms that reduce friction in daily life and help those around them understand when to lean in and when to give space.
Treatment and drugs
Pityriasis rubra pilaris is treated with a mix of skin care, prescription medicines, and close follow-up to calm inflammation, reduce scaling, and protect the skin barrier. Many start with thick, fragrance-free moisturizers, keratolytic creams (such as urea or salicylic acid), and short courses of topical steroids or calcineurin inhibitors to ease redness and itch while softened scale sheds. For widespread or stubborn PRP, doctors often use oral retinoids (like acitretin or isotretinoin) to slow down skin cell buildup; other options include methotrexate, cyclosporine, or biologic drugs that target specific immune signals when first-line treatment isn’t enough. Phototherapy (narrowband UVB) can help some people, especially when combined with moisturizers, though it’s not right for everyone. Finding the right therapy can take some time, so your doctor may adjust your dose to balance benefits and side effects and will monitor labs regularly to keep treatment safe.
Non-drug treatment
Non-drug care for Pityriasis rubra pilaris focuses on easing itch, softening thick skin, and protecting areas that crack so daily tasks feel more manageable. Alongside medicines, non-drug therapies can reduce discomfort and support healing between flares. These steps often work best when used together and adjusted over time. They may also help when early symptoms of Pityriasis rubra pilaris first show up, like rough patches or tender, splitting skin on the palms and soles.
Apply thick, fragrance-free creams or ointments several times daily to lock in moisture. This helps soften rough patches and reduces tightness and itching.
Take short, lukewarm baths or showers, then pat dry and immediately apply moisturizer to seal in water. Adding a gentle bath oil can further reduce dryness.
Dermatologist-directed light treatment (often narrowband UVB) can calm inflammation and smooth scaling. Sessions are brief but repeated regularly for best effect in Pityriasis rubra pilaris.
Use soft dressings or liquid bandage on painful cracks to shield them from friction. This can reduce pain with walking and lower the chance of infection.
Your genes may have an impact on how drugs work for you
Some people with pityriasis rubra pilaris process medications differently because of inherited differences in liver enzymes that activate or clear drugs. Pharmacogenetic testing can sometimes guide choices or dosing for treatments like retinoids or immunomodulators, improving safety and effectiveness.
Pharmacological treatments
Pityriasis rubra pilaris can make skin feel tight, sore, and very dry, which can disrupt sleep, work, and everyday routines. Medicines aim to calm inflammation, soften thick scale, and ease itch so skin can heal. Treating early symptoms of pityriasis rubra pilaris may improve comfort and help prevent cracking or infections. Not everyone responds to the same medication in the same way.
Creams or ointments like triamcinolone or clobetasol reduce redness, swelling, and itch on active patches. Doctors may suggest short courses on thicker areas and milder strengths on thin skin to lower side effects.
Salicylic acid, urea, or lactic acid lotions help loosen thick scale and smooth rough plaques. These are often layered with moisturizers and steroids to improve penetration and comfort.
Non-drowsy options by day or sedating choices at night can take the edge off itch. Better sleep can make daytime symptoms easier to manage.
Acitretin (adults) and isotretinoin (often used off-label) can thin plaques and reduce scaling across the body. Blood tests and pregnancy precautions are essential during treatment.
Genetic influences
Many families ask whether pityriasis rubra pilaris is genetic. Most people with pityriasis rubra pilaris (PRP) have a sporadic form, meaning it appears without a known family history. Rarely, PRP runs in families due to changes in a gene called CARD14; this usually follows an autosomal dominant pattern, so a parent with the change has a 50% chance of passing it on, but symptoms can look different even within the same family. Having a gene change doesn’t always mean you will develop the condition. Because of this variability, some relatives may show psoriasis-like rashes while others have classic PRP or no skin problems at all. Genetic counseling and, in selected cases, testing for CARD14 may be considered for early-onset PRP, persistent cases across generations, or when several relatives are affected, though it isn’t typically needed for isolated adult-onset PRP.
Is Pityriasis rubra pilaris genetic?
Genetics play a limited, variable role in pityriasis rubra pilaris. Most cases are sporadic, but rare inherited forms exist, often linked to CARD14 gene changes, which can run in families in an autosomal dominant pattern. Genetic testing is uncommon.
Pharmacogenetics—how genetics influence drug effects
People with pityriasis rubra pilaris (PRP) often find that one medicine helps a lot while another barely moves the needle. In a small number of families, changes in a gene called CARD14 have been linked to PRP and point to immune pathways that some newer biologic drugs can target. In those situations, a dermatologist may consider trying biologics that act on those pathways, but the evidence is limited to case reports and small studies, so responses still vary. There isn’t a standard pharmacogenetic test to choose the “right” PRP treatment; pharmacogenetic testing for pityriasis rubra pilaris isn’t routinely recommended, though genetic testing may be discussed in early-onset or familial cases to help confirm the diagnosis and guide options. For commonly used medicines like retinoids, methotrexate, or cyclosporine, doctors adjust dosing based on your overall health and lab monitoring rather than gene results. Genetics is only one factor in how treatments work; your age, other health conditions, and concurrent medications also shape response and side-effect risk.
Interactions with other conditions
Day to day, living with Pityriasis rubra pilaris (PRP) alongside another health issue can change how often flares happen and how tough they feel. Doctors call it a “comorbidity” when two conditions occur together. PRP has a recognized link with HIV; in people with HIV, PRP can be more widespread and stubborn, and skin symptoms often improve when HIV is well controlled. Early symptoms of Pityriasis rubra pilaris can resemble psoriasis, so if you already have psoriasis, your care team may look closely at skin features and tailor treatment so both conditions are covered. Very rarely, PRP has appeared alongside certain cancers as a “paraneoplastic” sign, but a general cancer workup isn’t recommended unless other red flags are present. When PRP causes widespread redness and scaling, the skin barrier is weaker, which can raise the risk of secondary bacterial infections and make dehydration or fever from another illness worsen the skin. If you also have liver or kidney disease, some PRP medicines (like retinoids or methotrexate) may need dose changes or different options to keep treatment safe.
How genes can cause diseases
Humans have more than 20,000 genes, each carrying out one or a few specific functions in the body. One gene instructs the body to digest lactose from milk, another tells the body how to build strong bones and another prevents the body's cells from beginning to multiply uncontrollably and developing into cancer. As all of these genes combined are the building instructions for our body, a defect in one of these genes can have severe health consequences.
Through decades of genetic research, we know the genetic code of any healthy/functional human gene. We have also identified that in certain positions on a gene, some individuals may have a different genetic letter from the one you have. We call these hotspots "Genetic Variations" or "Variants" in short. In many cases, studies have been able to show that having the genetic letter "G" in the position makes you healthy, but having the letter "A" in the same position disrupts the gene function and causes a disease. Genopedia allows you to view these variants in genes and summarizes all that we know from scientific research, which genetic letters (Genotype) have good or bad consequences on your health or on your traits.
History
Throughout history, people have described stubborn, reddish skin that peeled in fine flakes and formed tiny plugs around hair follicles. A child might be remembered for rough, sandpapery patches on the elbows and knees; an adult for salmon‑colored plaques that seemed to spread in islands across the trunk. Families sometimes recalled winters when hands and feet cracked and thickened, making everyday tasks painful. These lived details echo what we now recognize as pityriasis rubra pilaris.
First described in the medical literature as a distinct pattern in the 19th century, it was initially grouped with other scaly rashes. Early doctors focused on what they could see: follicle‑centered bumps, diffuse redness, and areas of normal skin that appeared like “islands” in a red sea. Over time, descriptions became more precise, separating pityriasis rubra pilaris from psoriasis and eczema, which can look similar at first glance but follow different courses and respond to different treatments.
From early theories to modern research, the story of pityriasis rubra pilaris has been one of careful observation followed by genetic insight. Clinicians charted patterns—some people had short‑lived skin changes after an illness, while others developed long‑lasting disease beginning in childhood. In recent decades, advances in genetics clarified that while most cases arise without a known cause, some familial forms are linked to changes in a gene that influences how skin cells grow and mature. This helped explain why the condition can run in families and why it behaves differently across types.
Medical classifications changed as experience grew. Subtypes were proposed based on age at onset, duration, and features such as nail thickening or palm and sole involvement. This framework guided care and research, and it remains in use today with updates as new evidence emerges. Not every early description was complete, yet together they built the foundation of today’s knowledge.
As treatments evolved—from emollients and coal tar to modern vitamin A–related medicines and immune‑targeting therapies—outcomes improved. People with pityriasis rubra pilaris now benefit from clearer guidance on what to expect, including periods of flare and remission and the possibility of long‑term control. Looking back helps explain why diagnosis can still take time: the condition is uncommon, overlaps with better‑known disorders, and can shift in appearance over weeks to months.
Each stage in history has added to the picture we have today. The everyday experiences recorded by patients and clinicians shaped the definitions, and genetics added another layer of understanding. This combined history continues to inform how pityriasis rubra pilaris is recognized, discussed, and treated in clinics around the world.