Palmoplantar Pustulosis vs Psoriasis: What Is the Difference?
If you have been diagnosed with palmoplantar pustulosis (PPP), you may have heard it described as 'a type of psoriasis.' You may even have been misdiagnosed with psoriasis first, as I was.
While PPP and psoriasis share some characteristics, they are not the same condition. Understanding the differences matters: it affects how your condition is treated, what triggers to look for, and how you manage it long-term.
While PPP and psoriasis share some characteristics, they are not the same condition. Understanding the differences matters: it affects how your condition is treated, what triggers to look for, and how you manage it long-term.
What is Psoriasis?
Psoriasis is a chronic autoimmune skin condition that causes rapid overproduction of skin cells, resulting in thick, scaly, raised plaques. These plaques most commonly appear on the elbows, knees, scalp, and lower back, but can appear anywhere on the body.
Psoriasis affects approximately 2–3% of the global population. It comes in several forms, including plaque psoriasis (the most common), guttate, inverse, erythrodermic, and pustular psoriasis.
Psoriasis affects approximately 2–3% of the global population. It comes in several forms, including plaque psoriasis (the most common), guttate, inverse, erythrodermic, and pustular psoriasis.
What is Palmoplantar Pustulosis?
Palmoplantar pustulosis is a rare, chronic inflammatory skin condition characterised by recurring, sterile pustules, small blisters filled with non-infectious fluid, that appear exclusively on the palms of the hands and the soles of the feet.
Unlike plaque psoriasis, PPP does not cause the raised plaques seen elsewhere on the body. The pustules in PPP dry out and leave behind brown spots, scaling, and cracked skin. The condition cycles through flare-ups and partial remissions.
PPP is significantly rarer than psoriasis, affecting less than 0.1% of the population, and is more common in middle-aged women.
Unlike plaque psoriasis, PPP does not cause the raised plaques seen elsewhere on the body. The pustules in PPP dry out and leave behind brown spots, scaling, and cracked skin. The condition cycles through flare-ups and partial remissions.
PPP is significantly rarer than psoriasis, affecting less than 0.1% of the population, and is more common in middle-aged women.
Key Differences: PPP vs Psoriasis
Location
Psoriasis can appear anywhere on the body. PPP is limited to the palms of the hands and the soles of the feet, hence the name 'palmoplantar', meaning 'palms and soles'.
Appearance
Psoriasis typically presents as raised, red, silvery-scaled plaques. PPP presents as deep-set, yellowish-white pustules that are not raised in the same way, and which eventually turn brown and flake off. The skin in PPP often looks more blistered and cracked than classically scaly.
Smoking as a trigger
This is one of the most striking differences. Research consistently shows that 90–95% of PPP patients are current or former smokers, a far higher association than in plaque psoriasis. Smoking is considered one of the primary drivers of PPP, and quitting is often a key part of management.
Treatment response
Many treatments that work well for plaque psoriasis, including certain biologics, have shown more limited effectiveness in PPP. PPP is often described by both patients and dermatologists as one of the most treatment-resistant skin conditions. This is partly why many PPP patients explore lifestyle-based and natural approaches.
Genetics and family history
Both conditions have a genetic component. However, PPP does not require the same HLA-Cw6 gene variant associated with plaque psoriasis, suggesting they have distinct genetic pathways despite some overlap.
Association with other conditions
PPP is associated with SAPHO syndrome (Synovitis, Acne, Pustulosis, Hyperostosis, Osteitis), a condition involving joint and bone inflammation. Psoriasis is more commonly associated with psoriatic arthritis. Both conditions are linked to an increased risk of cardiovascular disease and metabolic syndrome.
Why PPP Is So Often Misdiagnosed
I was misdiagnosed multiple times before finally receiving a correct PPP diagnosis. At different points, doctors suggested eczema, a fungal infection, and even scabies.
This is common, and there are good reasons for it:
This is common, and there are good reasons for it:
- PPP is rare, many GPs have never seen a case
- In early stages, the pustules can resemble dyshidrotic eczema or fungal infections
- PPP has no single definitive blood test, diagnosis is primarily clinical
- Awareness of PPP among non-dermatologists is low
Can You Have Both Psoriasis and PPP?
Yes. Some people have plaque psoriasis elsewhere on their body and PPP on their hands and feet simultaneously. The conditions can co-exist, which sometimes further complicates diagnosis and treatment decisions.
My Experience: From Misdiagnosis to Understanding
Living with an undiagnosed or misdiagnosed skin condition is exhausting and demoralising. For months, I was treated for conditions I did not have, while PPP continued to worsen.
Once I understood what I was actually dealing with, a rare, autoimmune, smoking-linked inflammatory condition specific to the palms and soles, I could start making informed decisions about how to manage it. That clarity was the beginning of my recovery.
If you have recently been diagnosed with PPP, I hope this comparison helps you understand your condition better. Knowledge is not just comfort, it is strategy.
Once I understood what I was actually dealing with, a rare, autoimmune, smoking-linked inflammatory condition specific to the palms and soles, I could start making informed decisions about how to manage it. That clarity was the beginning of my recovery.
If you have recently been diagnosed with PPP, I hope this comparison helps you understand your condition better. Knowledge is not just comfort, it is strategy.
If you are unsure whether you have PPP or another skin condition,
please consult a dermatologist. A correct diagnosis is the most
important foundation for effective treatment.
