Top Tips: Managing Psoriasis in Children

Dr George Moncrieff Discusses Best Practice in the Recognition and Treatment of Psoriasis and Related Comorbidities in Children, Providing Five Top Tips for Management in Primary Care

Psoriasis is a chronic, immune-mediated, inflammatory, dry skin disease. The condition is characterised by well-demarcated, red patches of abnormal skin with silvery scales.^1,2 There are several forms of psoriasis affecting the skin and nails, including:¹

• chronic plaque psoriasis (incorporating scalp psoriasis, flexural psoriasis, and facial psoriasis)
• localised pustular psoriasis of the palms and soles
• guttate psoriasis
• nail psoriasis
• erythrodermic and generalised pustular psoriasis.

The differences in presentation between the types of psoriasis are summarised in Box 1.³ 

Of these, chronic plaque psoriasis is the most common across all age groups, accounting for 80–90% of all cases.¹

Psoriasis varies in severity, and can have a significant impact on quality of life.⁴ The condition follows a remitting–relapsing course, with flares and remissions over many years.⁴ Psoriasis is also associated with comorbidities such as cardiovascular disease (CVD), psychological illness, and psoriatic arthritis (PsA),^4,5 but, in my experience, most patients seek medical advice for their skin symptoms.

Around one-third of all cases of psoriasis start in childhood.⁶ However, the diagnosis and management of psoriasis in children in primary care can be challenging for a number of reasons:

• although UK and European studies suggest that the prevalence of psoriasis in children aged less than 18 years is around 0.55–1.4%, it is rarely encountered it in primary care^4,5,7
• GPs do not commonly need to make a management decision on therapy for psoriasis in children, so our experience with this is often limited
• many topical therapies for treating psoriasis in adults are not licensed in children, or are only licensed for use in those aged 12 years and over
• there are few clinical guidelines on management in primary care, and they generally advise that all children with psoriasis should be referred for specialist advice—as recommended in NICE Guideline 153, Psoriasis: assessment and management.⁸

Although children with psoriasis are often managed jointly with secondary care, primary care has an important role to play, including in:

• the management of mild disease
• the treatment of intercurrent flares while awaiting specialist support
• the provision of shared care
• being vigilant for treatment failure or the development of complications.

The contribution of primary care has become even more significant in the COVID-19 pandemic, during which the availability of specialist advice has been limited.⁹ This article covers best practice in the delivery of interim care to children with psoriasis. 

1. Examine Children with Psoriasis Sensitively

For many patients with psoriasis, one of the most upsetting consequences is the response of other people: reactions of disgust, and even fear that the skin disease may be contagious, are not unusual. This can be very distressing, particularly for a child. GPs must be sensitive to this. Careful examination, including touching and feeling any affected areas, is important—although, of course, permission must be obtained, and appropriate hygiene measures observed.

Recognising Psoriasis in Children

Diagnosis is usually straightforward: sharply demarcated, erythematous plaques with silvery scales are usually seen in children with psoriasis, as they are in adults,¹⁰ although they may be less obvious on pigmented skin. As in adults,¹⁰ the distribution of disease is also indicative, as the condition typically affects the extensor surfaces (elbows and knees), trunk, flexures, sacral and natal clefts, scalp and behind the ears, and navel. Guttate psoriasis is the most common form of the condition in children and young people.¹¹ Scalp disease, experienced by around 80% of children with psoriasis, is more common from the teens, and can be especially tricky to manage.¹² Nails are involved in up to 50% of all cases of psoriasis, and are a marker of increased risk of PsA.¹³ Signs of nail disease, such as pitting, onycholysis, and small salmon patches, may be very subtle, and could be missed if not examined for carefully.¹³ Nail changes can help to clinch the diagnosis and should alert the physician to the increased risk of PsA.

Differentiating Psoriasis from Eczema

Occasionally, more widespread, superficial psoriasis can resemble eczema.¹⁴ However, in eczema, the affected areas are typically less well demarcated;¹⁴ in my experience, there is often both post-inflammatory hypo- and hyperpigmentation in eczema, whereas in psoriasis sharp margination is evident,¹⁰ and typically only hypopigmentation is seen. Both conditions can be devastatingly itchy in children, and this symptom of childhood psoriasis is often under-recognised by healthcare professionals.

2. Identify and Manage Comorbidities of Psoriasis in Children

Looking for comorbidities of psoriasis, and managing them sympathetically and effectively, are essential components of the care of any child with psoriasis.^5,6,8 The comorbidities of most relevance to the paediatric population are discussed in the following sections.

Psychological Illness

Psychological illness is common in people of all ages with psoriasis,⁶ especially when ‘high-impact’ areas (areas of the body that are visible to others and/or sensitive and difficult to treat) are involved.^8,15 In my experience, facial psoriasis, which is visible, is more common in children than in adults, and may cause greater psychological harm than psoriasis in other areas (for example, by precipitating bullying and triggering depression, anxiety, low self-esteem, and even suicidal ideation).⁶

The sequelae of psoriasis in children demand sensitive assessment and appropriate treatment and support.^6,8 It is also important to remain vigilant for the possibility of ‘risky behaviours’—including alcohol and substance abuse—in children with psoriasis.⁶

PsA

PsA is a chronic, inflammatory arthritis that typically presents with joint stiffness, pain, or swelling, particularly in the morning.^6,10,13 The condition accounts for approximately 6–8% of all cases of juvenile arthritis, and the inflammatory arthritis precedes the skin disease in about half of children with PsA.¹³

As in adults, PsA in children is a destructive condition that, without early identification and intervention, can progress to permanent joint damage and disability.^6,13 Therefore, it is imperative that all physicians caring for children with, or at risk of developing, psoriasis are aware of the possibility of juvenile PsA. A low threshold for urgent referral to paediatric rheumatology services is necessary if PsA is suspected.^8,16

Children with psoriasis should be screened annually for PsA.^8,16 The Psoriasis Epidemiology Screening Tool (PEST; bit.ly/33sU9y9) is a validated screening tool for PsA that is endorsed by NICE.^10,17 However, like other PsA screening questionnaires, it does not detect axial arthritis or inflammatory back pain.¹⁰

Interestingly, the gene associated with early onset psoriasis, HLA-C*06:02, is not linked to PsA,¹⁸ so individuals presenting with this pattern are less likely to develop PsA. 

Uveitis

The inflammatory eye condition uveitis occurs in an estimated 1.5–25% of patients with PsA, but does not occur in the absence of PsA or where the disease is limited to the skin.⁶ Screening for the condition should only be conducted in patients with PsA.⁶

Obesity

Overweight and obesity are more common in children with psoriasis.¹⁹ The association between psoriasis and central adiposity is strongest in children with severe psoriasis.¹⁹ Adipose tissue is metabolically active, and increased adipose tissue equates to elevated levels of pro-inflammatory cytokines, such as interleukin-6, and decreased levels of adiponectin, an anti-inflammatory adipokine.²⁰ In turn, this leads to the upregulation of T helper cells, which are involved in the pathogenesis of psoriasis.²⁰

Obesity may contribute to some of the other comorbidities evident in psoriasis, such as insulin resistance, dyslipidaemia, type 2 diabetes, non-alcoholic fatty liver disease (NAFLD), and CVD, although type 2 diabetes, NAFLD, and CVD have been shown to be associated with psoriasis independently of confounding risk factors.⁶ These conditions are less relevant to the paediatric population.

Children with psoriasis and obesity and their parents or carers should be offered preventative advice, healthy lifestyle information, and support for behavioural change tailored to meet their needs.⁸

Rheumatoid Arthritis and Inflammatory Bowel Disease

Both rheumatoid arthritis and Crohn’s disease are more common in children with psoriasis.⁵ The prevalence of ulcerative colitis is also higher in patients with psoriasis, but without statistical significance.⁵

Cumulative Life Course Impairment

As in adults, psoriasis in children can have a profound impact on quality of life and emotional, social, and academic functioning,⁶ and this can often come at a critical stage in a child’s life. The chronic and recurrent nature of psoriasis, in combination with the stigmatisation, low self-esteem, physical symptoms, and treatment burden associated with the condition, can have a devastating, irreversible impact on opportunities, achievements, and psychological health, especially for an individual presenting with psoriasis in childhood. These severe, life-changing consequences are termed cumulative life course impairment (CLCI), and can only be mitigated if the disease is adequately managed.^6,21

3. Use the Tools Available to Assess Disease Severity

The extent of body surface area (BSA) affected by psoriasis can be estimated to give a measure of severity by using the Lund–Browder Diagram (see Figure 1, and: chemm.hhs.gov/burns.htm);²² this is traditionally used for burns, but has been endorsed by NICE for use in adults with psoriasis.¹⁰ However, this does not take into account high-impact areas such as the face or genitalia, which may only involve a very small percentage of the skin surface but have a considerable impact on the patient. In addition, NICE states that BSA assessment is not validated for use in children and young people.⁸

The Children’s Dermatology Life Quality Index (CDLQI; bit.ly/3rwXrbw) is a validated questionnaire that explores the impact psoriasis has on quality of life,²³ covering issues including itch, embarrassment, relationships, activities, and sleep.²⁴ The cartoon form may be especially useful for children aged 4–12 years. It is more useful to review each of the answers to the CDLQI than to focus on the total score, as doing this can highlight issues that are having a considerable impact but may not have been raised by the patient—for example, the questionnaire specifically enquires about the effect a patient’s treatment is having on their everyday life.

The Psoriasis Area and Severity Index (PASI; bit.ly/3tJIqG7) is an objective, validated tool for use in secondary care and clinical trials.²⁵ The PASI is not validated for use in children and young people, and in my opinion it should only be used in a specialist setting.⁸   

4. Manage Psoriasis in Children According to its Severity

In my experience, psoriasis in children is often undertreated—this may happen for a number of reasons, including:

• fear of the potential long-term adverse effects of treatment
• lack of licensed therapy options in children
• failure to recognise the severity of the disease
• the fact that children respond to treatments differently to adults and we are less familiar with these differences in primary care.

Recent evidence suggests that undermanagement of childhood psoriasis can lead to a compromised quality of life and increased comorbidities.^6,21 There is a move to more effective control,²⁶ especially as management does not need to be complicated.

Triggers

The first step in the management of children with psoriasis is to identify any obvious triggers and address them when possible. Examples of common triggers for psoriasis are provided in Box 2.^6,27

Topical Therapies

Topical therapies are the mainstay treatments for psoriasis initiated in primary care. Some are not licensed for use in children at all, whereas others are only licensed in children more than 12 years of age. However, sometimes there are few alternatives to these agents. I believe that topical treatments should be considered and offered to children with psoriasis when appropriate, alongside plenty of background advice and information.

NICE recommends that toxicity, tolerability, and response to treatment should be reviewed 2 weeks after starting a new topical therapy in children.⁸ In children whose psoriasis has not responded satisfactorily to a topical treatment, discuss any difficulties with application or adherence with the patient and their parents or carers before changing to an alternative treatment.⁸

Emollients

Symptoms of psoriasis such as dry skin, roughness and, in my experience, itching may be relieved by avoiding harsh detergents and shampoos and by the regular use of a leave-on emollient of the patient’s choice. Emollients have been shown to normalise cell differentiation, and have useful anti-inflammatory effects.²⁸

NICE advises that people of all ages with psoriasis should be offered an emollient as a first-line treatment, and given advice and support on their correct use and application.⁸ Healthcare professionals should discuss the variety of formulations available with the patient and, depending on their preference, offer:⁸

• cream, lotion, or gel for widespread psoriasis
• lotion, solution, or gel for the scalp or hair-bearing areas
• ointment to treat areas with thick adherent scale.

See the British National Formulary for Children (BNFc; bnfc.nice.org.uk) for guidance on the use of emollients.

Topical Corticosteroids

Some topical corticosteroids (TCS) are not licensed for the treatment of psoriasis in children, and those that are should be used with caution. They are unsuitable for long-term use in people of all ages—a treatment break of 4 weeks is necessary between courses of treatment with potent or very potent TCSs—and very potent TCSs should not be used in children and young people.⁸ In addition, use of TCSs can result in steroid atrophy, instability of psoriasis, rebound upon discontinuation, and systemic side effects; hence, NICE recommends that children who are prescribed a TCS of any potency should be reviewed at least annually to assess for the presence of adverse effects.^8,29

TCSs are useful for treating relatively localised disease, and address the inflammatory elements of psoriasis.²⁹ TCSs only need to be applied once daily,⁸ ideally as an ointment at bedtime. When choosing a strength, it is important to take into account the site, the severity and thickness of plaques, and the patient’s age. NICE points out that the face, flexures, and genitals are particularly vulnerable to steroid atrophy; therefore, TCSs should only be used for 1–2 weeks per month.⁸ Also, it should be taken into account that the relatively high BSA to weight ratio of very little children means that they are more vulnerable to systemic sequelae.

My practice is to start with daily application of a TCS of appropriate potency, and then reduce the frequency of application—first to alternate days and then to weekend-only therapy—rather than to stop treatment abruptly and risk a rebound. Prescribing a variety of strengths of TCS for the same site risks confusion, although different body areas may still need different strengths of TCS.

Clobetasol shampoo³⁰ is not licensed for use in children, but I believe that it is a viable option for severe, itchy scalp psoriasis. In my experience, it only needs to remain in contact with the scalp for around 15 minutes before being thoroughly rinsed out. I would only prescribe this to a child aged less than 1 year after discussion with a specialist.

TCSs can be used safely alongside other topical treatments, such as vitamin D analogues.⁸

Vitamin D Analogues

Vitamin D analogues inhibit the proliferation and promote the differentiation of keratinocytes,³¹ and thus help to address the hyperkeratosis seen in chronic stable plaque psoriasis. Some vitamin D analogues are not licensed for use in childhood psoriasis at any age, and others are only licensed for this indication from 12 years of age. However, multiple studies have demonstrated the safety and efficacy of calcipotriol in children.^32,33

NICE recommends use of vitamin D analogues alongside TCSs, and during treatment breaks from TCS therapy to maintain disease control.⁸ Examples of vitamin D analogues are listed in Box 3.^34–36

Topical vitamin D analogues can cause irritation;³² therefore, I would not generally advise using these on the face or flexural areas, including the genitalia. Calcitriol and tacalcitol may be less irritating than calcipotriol;³⁷ in my experience, calcitriol is the least irritant, and I use this to treat flexural psoriasis in children who are aged mnore than 12 years of age, but I always introduce it very gradually (initially, up to twice a week) and only increase it if it is tolerated. Again, because of the relatively high BSA to weight ratio in smaller children, caution should be exercised regarding the quantities prescribed, especially in those with a large BSA affected by psoriasis.

The combination product calcipotriol/betamethasone foam is only licensed for the treatment of psoriasis from 18 years;³⁸ however, in line with advice from secondary care colleagues, I use this in children from 12 years of age, but I limit the course to a maximum of 4 weeks. In adults, this product is now licensed for maintenance therapy, applied twice a week on non-consecutive days,³⁸ and this is something that I would consider in a child (off licence) if they have responded well and in appropriate circumstances. This combination foam is highly effective for scalp disease,³⁹ and although not licensed for this indication in children, it is an option I offer to children aged more than 12 years.

Dithranol

Dithranol is not licensed for use in children, and is only recommended by NICE for use in children with treatment-resistant psoriasis of the trunk or limbs in a specialist setting.⁸ Regrettably, the most easily used cream preparation (which was available in a number of strengths) is no longer being manufactured, so this modality is now less accessible.

Coal Tar Preparations

Tars can be highly effective treatments for itch, scaling, and inflammation, but some of these agents smell, and they can be difficult to apply.³⁷ However, they are licensed for use in children with psoriasis and, although in my experience they can act as an irritant (causing folliculitis or photosensitivity), they are generally well tolerated. NICE states that they can be used once or twice daily for chronic plaque psoriasis of the trunk and limbs.⁸

Topical Immune Modulators

Topical immune modulators are not licensed for the treatment of psoriasis, but are my treatment of choice for facial psoriasis; typically, improvement can be seen within 72 hours. In my experience, they are safe and effective for flexural and genital psoriasis.

5. Understand When to Refer to Secondary Care

With more extensive or resistant disease, referral to secondary care may be indicated. The therapeutic options available in secondary care are shown in Box 4.^8,37,40,41

Biological treatments are available and licensed for use in children with ongoing high CDLQI and PASI scores, and who have not responded to standard systemic therapy, such as ciclosporin, methotrexate, or phototherapy, or in whom these options are contraindicated or not tolerated.^37,42

Summary

In general, the younger an individual is when psoriasis first manifests, the more severe and recalcitrant their condition is likely to be. This may be because they have inherited a greater number of psoriasis-associated genes. The role of the GP includes looking for potential comorbidities, especially those that the patient is unlikely to present with (such as arthritis or obesity). When there is a family history of psoriasis, it is especially important that the practitioner is vigilant for PsA. 

Investing time with the patient and their parents or carers from the outset to establish a good relationship and a shared understanding is immensely valuable to promote good ongoing care. Producing a clear, written treatment plan for the patient and their family or caregivers ensures understanding, and it is critical to involve the child and their parents or carers in decisions and provide appropriate information. Finally, effective two-way communication and collaboration between primary and secondary care is fundamental to good care. This will often include pharmacists, as some of our recommendations may be off licence. Occasionally, other members of the primary healthcare team, the school nurse, and even counsellors may need to be involved.

The chronic, relapsing nature of psoriasis can have a considerable impact on CLCI, especially when the disease starts in childhood. Thus, managing the disease effectively is all the more imperative.

Useful sources of information for patients and healthcare professionals can be found in Box 5.

Dr George Moncrieff

GP, Oxfordshire; past Chair of the Dermatology Council for England; past Committee member of the Primary Care Dermatology Society