Psoriasis on the feet

Psoriasis on the feet is a chronic inflammatory skin disease with an immunological basis, belonging to the group of autoimmune diseases. It most commonly manifests as palmoplantar psoriasis (psoriasis palmoplantaris), affecting the plantar surface of the feet. The condition is characterized by excessive proliferation (accelerated division) of keratinocytes and a chronic inflammatory state of the dermis. Changes on the feet can significantly impede walking, cause pain and skin fissures, and thereby impact the patient's quality of life. Unlike athlete's foot, psoriasis is not an infectious disease and is not transmitted through direct contact.

Psoriasis on the feet – what it looks like

The clinical picture of foot psoriasis depends on its form, but most commonly observed are:

Clearly demarcated, erythematous (red) inflammatory lesions, covered with thick, silvery scales.
Hyperkeratosis, which is a significant thickening of the stratum corneum.
Cracks and fissures in the skin, especially in the heel and forefoot areas.
Dryness and roughness of the skin.
In the pustular variant – sterile (non-infected) pustules on an erythematous base.

The changes on the feet are often symmetrical. The skin may be significantly thickened and painful under pressure, distinguishing it from typical psoriatic lesions found on elbows or knees.

In a dermatological examination, classic symptoms of psoriasis may be observed, such as:

The candle wax sign (after scraping the scale, a sheen appears).
Auspitz sign (pinpoint bleeding after removing the scale).

The differential diagnosis primarily includes:

athlete's foot (tinea pedis),
contact dermatitis,
calluses and corns,
palmoplantar keratoderma of other etiology.

In case of doubt, mycological examination (to exclude fungal infection) or skin biopsy is performed.

Psoriasis on the feet – symptoms

Symptoms of foot psoriasis can be both localized and systemic (if other forms of the disease coexist).

Most common localized symptoms:

chronic dryness and scaling of the skin,
pain while walking,
burning and tightness of the skin,
cracks leading to bleeding,
excessive keratinization making it difficult to move,
periodic exacerbations with increased redness and scaling.

In the pustular palmoplantar form, the following may occur:

painful pustules filled with purulent (sterile) content,
swelling and severe inflammation.

In some patients, there is a co-occurrence of:

psoriatic arthritis (PsA) – characterized by joint pain and swelling,
nail changes (onycholysis, pitting of the nail plate).

Aggravating factors include:

stress,
infections,
mechanical injuries (the so-called Koebner phenomenon – formation of lesions at the site of injury),
smoking,
obesity and metabolic syndrome.

It is important to emphasize that psoriasis is a chronic disease with a relapsing course – periods of remission alternate with exacerbations.

Psoriasis on the feet – treatment

Treating psoriasis of the feet requires a multi-directional approach and individualized therapy. Due to the thick stratum corneum in this area, the effectiveness of topical treatment may be limited, thus combination therapy is often used.

1. Topical Treatment

The basis of therapy involves preparations applied directly to the lesions:

Topical glucocorticosteroids – reduce inflammation and itching.
Vitamin D3 analogs (calcipotriol) – normalize keratinocyte proliferation.
Keratolytics (salicylic acid, urea) – soften and remove excessive keratinization.
Tar preparations – used less frequently due to odor and risk of irritation.

2. Phototherapy

In moderate and severe cases, the following are used:

UVB 311 nm (narrowband phototherapy),
PUVA (psoralen + UVA).

Phototherapy has anti-inflammatory and immunomodulatory effects.

3. Systemic Treatment

In severe, resistant forms:

methotrexate,
cyclosporine,
acitretin,
biologic drugs (TNF-α inhibitors, IL-17, IL-23).

The decision on systemic therapy is made by a dermatologist after assessing the disease's severity and impact on quality of life.

4. Supportive Measures

regular use of emollients to restore the hydro-lipid barrier,
avoiding mechanical injuries and excessive pressure,
wearing breathable footwear,
weight reduction (if indicated),
cessation of smoking.

In case of excessive keratinization, professional podiatric procedures involving controlled removal of the keratinized epidermis layer can be helpful in improving the penetration of topical medications. Each procedure should be preceded by a dermatological consultation to avoid exacerbation of lesions.