Hand Psoriasis: Treatment and Care

Hand psoriasis is a collective term for lesions affecting the dorsal surfaces of the hands, palms, fingers, and nail folds, often involving the nails. Although often limited in area, this condition significantly impairs quality of life due to pain, cracking, itching, impaired fine motor skills, and the social visibility of the rash. For some patients, this is the only or primary area of disease activity. [1]

Hands are considered a difficult area to treat: dense hyperkeratosis, frequent maceration and microtrauma, and exposure to detergents and gloves reduce the effectiveness of standard topical treatments and increase the risk of relapse after discontinuing therapy. Therefore, consistent control requires appropriate dosage forms, the use of occlusion, keratolytics, and a willingness to use phototherapy or systemic agents if response is insufficient. [2]

Hand psoriasis is heterogeneous in phenotype, ranging from classic plaques on the dorsum of the hands to hyperkeratotic palmar forms and pustular variants. Concomitant nail involvement is common and further limits function. A significant proportion of patients have symptoms or are at high risk for psoriatic arthritis, necessitating regular screening. [3]

The current pathogenetic model relies on the interleukin-23-interleukin-17 axis, T-cell and keratinocyte activation. Specific inflammatory profiles and mechanical stress have been identified for palmoplantar forms, explaining their resistance to therapy and the benefit of targeted approaches. [4]

Codes and terminology

In ICD-10, hand lesions are described in block L40 "Psoriasis," most commonly L40.0 "Vulgar psoriasis." There is no specific code for "hand psoriasis"—location is indicated in the clinical diagnosis. Pustular forms of the hands may be coded as L40.1. [5]

In ICD-11, the basic code for plaque psoriasis is EA90.0. Localization is refined by post-coordination of the anatomical modifier "hand palm fingers," which improves the accuracy of severity and treatment outcomes by zone. Pustular forms of the hands can be classified under EA92 and refined by modifiers. [6]

Table 1. How to code hand psoriasis

Classifier	Basic code	Commentary on hands	How to clarify
ICD-10	L40.0 L40.1	Vulgar or pustular psoriasis	The localization of "hands, palms, fingers" is prescribed in the diagnosis
ICD-11	EA90.0 EA92	Plaque and pustular phenotypes	Post-coordination of anatomical modifiers for the hands and fingers

The use of post-coordination in ICD-11 facilitates the audit of results for “difficult areas” and the coordination of treatment goals. [7]

Why Hands Are a Special Zone: Burdens and Everyday Limitations

The overall prevalence of psoriasis is approximately 2-3%, with hand involvement common and disproportionately reducing quality of life due to pain, cracks, bloody crusts, embarrassment, and limitations in hand function. Associated nail changes further exacerbate the burden. [8]

Even with a small area of activity on the hands, escalation of therapy according to guidelines is often necessary, as topical regimens without occlusion and keratolytics provide short-term results. Applying "targeted treatment" with regular reassessment of indicators helps promptly change tactics. [9]

Palmar skin is thicker, has a different barrier, and is subject to constant friction and contact with chemical agents. This reduces drug penetration and provokes the Koebner phenomenon. More potent steroids in appropriate forms, keratolytics, and delivery techniques, including occlusion, are required. [10]

Comorbidities include depression, anxiety, and the risk of psoriatic arthritis with dactylitis and enthesitis of the hands. Patients with hand activity should undergo regular screening for psoriatic arthritis using validated questionnaires. [11]

Table 2. What makes the hands a "difficult area"

Factor	Consequences	Practical answer
Thick stratum corneum	Poor drug delivery	Forms of "ointment, cream, foam, gel" plus keratolytics and occlusion
Constant friction and water	Koebner crack phenomenon	Gentle hygiene, gloves according to protocol, craft prevention
Contact with allergens and irritants	Contact dermatitis overlay	Early assessment and patch testing when indicated
Visibility and function	High disease burden	Early step-up to phototherapy or systemic agents

The source of escalation recommendations is the EuroGuiDerm and AAD-NPF living guides. [12]

Causes, triggers and pathogenesis

Psoriasis is an immune-mediated inflammation with the interleukin-23-interleukin-17 axis playing a leading role. Activation of T-helper cells type 17 and cytokine cascades stimulate proliferation and disrupt the differentiation of keratinocytes, leading to hyperkeratosis and dermal inflammation. These mechanisms are equally relevant for the hands, but mechanical stress on the palms increases the persistence of lesions. [13]

Classic triggers include stress, microtrauma, smoking, obesity, infections, and medications. For hands, exposure to water, detergents, gloves containing allergenic components, and wet work can increase the risk of contact dermatitis and recurrence. [14]

Pustular palmoplantar forms have partially distinct inflammatory patterns; there is growing evidence supporting interleukin-23 inhibitors and targeted phototherapy.[15]

Understanding the pathogenesis allows planning long-term control with minimal stress: keratolytics for scale debridement, powerful topical glucocorticosteroids under occlusion in short courses, then a maintenance intermittent regimen, and, if necessary, phototherapy and systemic drugs. [16]

Clinical picture of hands: shapes and nails

Erythematous-squamous plaques with clear borders and dry white scales predominate on the dorsum of the hands. On the palms, hyperkeratotic plaques with painful cracks and sometimes pustules (in the pustular variant) are present. Itching and pain lead to sleep disturbances and a refusal to perform manual tasks. [17]

Nail psoriasis presents with pitting, "oil spot" sign, onycholysis, and subungual hyperkeratosis. These signs are important for recognizing psoriatic arthritis. Differentiation from onychomycosis is essential, which requires mycological testing. [18]

Some patients simultaneously present with palmar hyperkeratosis and signs of "hand eczema"—this does not rule out psoriasis. A proper diagnosis is based on a combination of clinical examination, dermatoscopy, and, if necessary, biopsy. [19]

The pustular palmar form is characterized by sterile pustules, pain, frequent recurrences, and a more pronounced impact on quality of life; it often requires phototherapy and systemic methods. [20]

Table 3. Clinical phenotypes on hands

Phenotype	Key Features	What makes life difficult	Frequent treatment steps
Plaque dorsum of the hands	Clear plaques of white scales	Visibility itching	High potency steroids calcipotriol
Palmar hyperkeratotic	Thick plaques cracks pain	Pain when working with hands	Keratolytics plus steroids under occlusion phototherapy
Pustular palmar	Sterile pustules recurrence	Pain and functional limitations	Targeted phototherapy systemic agents
Nail	Pitting "oil spot" onycholysis	Pain when grasping objects	Combination of external and systemic methods

Nail data and their differentiation from onychomycosis are the key to the correct tactics. [21]

Diagnostics

The first step is a clinical examination with dermatoscopy. Palmoplantar psoriasis is characterized by regular, pinpoint vessels on a red background and diffuse white scales; eczema often has yellow scales and an irregular vascular pattern. [22]

The second step is to rule out infections: a KOH test and culture if tinea manuum and onychomycosis are suspected. Dermatophytosis can mimic psoriasis and often lead to erroneous escalation. [23]

The third step is to evaluate the role of contact allergens and irritants. In chronic cases and with poor response to standard therapy, patch testing with basic series, expanded to include occupational allergens, is indicated. [24]

The fourth step is nail assessment and screening for psoriatic arthritis. A positive questionnaire increases suspicion and changes the threshold for systemic therapy. [25]

Table 4. Diagnostic minimum for "hand psoriasis"

Step	What are we doing?	When is enough?	When to expand
Examination plus dermatoscopy	We are looking for typical vessels and scales	A typical picture	Atypia, severe pain
Mycology	KOH microscopy seeding	Suspected tinea and onychomycosis	Before escalation of systemic therapy
Patch testing	Basic series of allergens at work	Relapses due to contact with chemicals	The therapy is not working as expected.
PsA screening	PEST every 6 months	With negative PEST	If the sum is ≥3, refer to a rheumatologist

Dermoscopy and mycology reduce the risk of diagnostic errors, patch testing helps to eliminate supporting triggers. [26]

Differential diagnosis: what most often masquerades as hand psoriasis

The main "masks" are chronic hand eczema, dyshidrotic eczema, tinea manuum, palmar keratoderma, and onychomycosis. Clinical and dermatoscopic signs, as well as laboratory tests, allow us to differentiate these conditions. [27]

Dyshidrotic eczema is characterized by vesicles and oozing, while tinea pedis presents with pain, brittle nails, and "black spots" in the affected hair on the hands. These are rare, but mycology remains the determining factor. Keratodermas have a different skin pattern and are often familial. [28]

Onychomycosis mimics nail psoriasis but requires antifungal therapy; without confirmation by KON PAS staining or culture, escalation of anti-psoriatic therapy is irrational.[29]

Table 5. Hand psoriasis versus similar diseases

Sign	Psoriasis of the hands	Hand eczema	Tinea manuum	Keratoderma	Onychomycosis
scales	White dry	Yellow wet	Diverse	Diffuse hyperkeratosis	Subungual detritus
Dermatoscopy	Regular pinpoint vessels	Irregular vessels	Peripheral peeling	Special dermolines	Not applicable
Itching pain	Often	Often	Often	Varies	Pain when pressed
Tests	Not always needed	Patch tests for chronic conditions	KOH sowing	Genetics according to indications	CON PAS sowing

A combination of dermatoscopy and targeted laboratory tests helps to differentiate. [30]

Dermoscopy: Landmarks for the Hands and Palms

Palmoplantar psoriasis is characterized by regular, pinpoint vessels on a diffuse red background and white scales; eczema is characterized by yellow scales and irregular vessels. These features are reproducible and help reduce the number of biopsies. [31]

Dermoscopy of nails in psoriasis reveals oil spots, continuous pits, subungual hemorrhages and hyperkeratosis; in onychomycosis - fragmentary longitudinal stripes and a "ruin-shaped" free edge, but the final distinction is made by mycology. [32]

Table 6. Dermatoscopy markers

Zone	Signs of psoriasis	Signs of alternatives
Palms	Regular pinpoint vessels, white scales	With eczema - yellow scales, irregular vessels
Nails	Oil stain, pits, subungual hemorrhages	In onychomycosis - detritus, "ruins" of the free edge

The use of dermatoscopy saves time and speeds up the start of proper therapy. [33]

Treatment: care, keratolytics and topical therapy

Basic care: daily emollients, skin barrier protection, reduced contact with water and irritants, and gloves for wet work. Before applying anti-inflammatory agents to severe hyperkeratosis, use salicylic acid or urea to soften and improve delivery. [34]

Topical glucocorticosteroids of high and ultra-high potency are first-line therapy for the hands, especially the palms. A course of treatment is usually 2-4 weeks daily, followed by a maintenance regimen of 1-2 times per week. Occlusion increases efficacy in thick plaques. [35]

Vitamin D analogs, particularly calcipotriol, are used as an alternative to or in alternation with steroids. A fixed combination of calcipotriol plus betamethasone in a gel or ointment provides a more rapid and profound response than monotherapy. Salicylic acid should not be used in a single application. [36]

New nonsteroidal agents: the phosphodiesterase-4 inhibitor roflumilast 0.3% and the AHR agonist tapinarof 1% have demonstrated efficacy and good tolerability in plaque psoriasis, including in complex localizations; for palmar forms, there is growing clinical data and case series. [37]

Table 7. Topical schemes for hands

Class	Form	Typical course	Notes
High potency steroids	Ointment cream foam	2-4 weeks daily → maintenance	Palm occlusion enhances the effect
Calcipotriol	Ointment gel	4-8 weeks	Alternating with steroids should be spaced out with keratolytics
Combination of calcipotriol plus betamethasone	Gel ointment	4-8 weeks	Quick answer for hyperkeratosis
Roflumilast 0.3%	Cream	According to the instructions	Suitable for long-term control and sensitive areas
Tapinarof 1%	Cream	According to the instructions	Data from RCTs on plaque phenotype

Long-term strategy - intermittent maintenance to prevent relapses and maintain the barrier. [38]

Phototherapy and targeted devices

Narrowband ultraviolet-B and targeted 308 nm excimer are effective for localized forms on the palms and fingers. Hairless skin facilitates radiation delivery. For hyperkeratosis, phototherapy is often combined with keratolytics and topicals. [39]

Home phototherapy with narrowband ultraviolet-B has been shown to be non-inferior to outpatient efficacy and to have a lower patient burden in the large randomized LITE trial; it is reasonable in chronic disease with frequent relapses. [40]

In refractory palmar forms, PUVA soaks or PUVA cream are used; evidence of efficacy exists, but risks and availability are taken into account. Comparative studies with excimer show comparable or superior dynamics across a number of regimens. [41]

Table 8. Phototherapy for hand psoriasis

Method	How to use	Who is it especially suitable for?	Safety Notes
Narrowband ultraviolet-B	Courses 3-5 times a week	Localized plaques of the palm and fingers	Erythema control eye protection
Excimer 308 nm	Pinpoint high doses	Thick lesions resistant to topicals	Accelerated response with less exposure to healthy skin
PUVA soaking cream-PUVA	Coursework according to the protocol	Refractory hyperkeratosis	Consider phototype and PUVA risks

The choice of method depends on the phenotype, availability and safety profile. [42]

Systemic therapy and biological agents

Indications for systemic therapy include persistent hand activity with impaired function and quality of life, inadequate response to optimal topical therapy and phototherapy, concomitant nail psoriasis, and/or suspected psoriatic arthritis. The decision is based on current recommendations and treatment goals. [43]

Interleukin-17 and interleukin-23 inhibitors demonstrate rapid and sustained effects in plaque psoriasis, including "difficult areas." Positive data are accumulating for palmoplantar and pustular phenotypes, particularly for the interleukin-23 class. [44]

Traditional systemic agents and apremilast remain options, taking into account comorbidities, pregnancy plans, and monitoring. The choice of molecule should take into account nail disease and the risk of psoriatic arthritis. [45]

The goal is to achieve low activity with a minimal area of damage and maintain remission against the background of a safe observation regime and prevention of triggers. [46]

Table 9. Systemic approaches: selection guidelines

Class	Strengths	When it is especially appropriate
Interleukin-17 inhibitors	Quick answer: "difficult areas"	Severe hyperkeratosis, need for rapid control
Interleukin-23 inhibitors	Stable remission at convenient intervals	Palmoplantar and pustular phenotypes, nails
Apremilast and traditional systemic	Moderate effectiveness	Mild comorbidities, preference for oral regimens

Reliance on EuroGuiDerm and AAD-NPF allows for standardization of selection and monitoring. [47]

Screening for psoriatic arthritis in patients with hand involvement

Any patient with hand psoriasis should undergo regular screening for psoriatic arthritis, particularly if they experience pain and morning stiffness in the hands, dactylitis, and nail involvement. Simple, validated questionnaires increase the detection of undiagnosed cases. [48]

The PEST questionnaire consists of 5 questions, with a score of 3 or more considered positive. It is recommended to administer the questionnaire every 6 months. A positive screening result prompts consultation with a rheumatologist and, if the diagnosis is confirmed, adjustment of anti-inflammatory therapy. [49]

The presence of psoriatic arthritis changes the goals of therapy, justifying the early selection of systemic and biological agents. The CASPAR classification criteria help verify the diagnosis at the rheumatological stage. [50]

Timely routing improves long-term prognosis of hand function and quality of life. [51]

Treatment goals and outcome monitoring

The "treat to target" approach aims to reduce the lesion area to 1% of the body surface area or less within 3 months of starting a new therapy and then maintain the result with assessments every 6 months. For the hands, it is reasonable to additionally record the absence of cracking and pain when gripping. [52]

Practical indicators: disappearance of painful cracks and pustules, restoration of hand function, ability to work without worsening of symptoms, no need for daily use of powerful steroids and maintenance of barrier function against emollients.[53]

If the goal is not achieved after an optimized external occlusion regimen and a course of phototherapy, escalation to systemic therapy according to guidelines is recommended. Regular reassessment prevents "getting stuck" on ineffective regimens. [54]

Safety management includes drug class monitoring and patient education on photoprotection during phototherapy and skin barrier care.[55]