While more common in adults, psoriasisalso affects select individuals of the pediatricpopulation. The presentation of psoriasisin children can be similar to thatseen in adults; however, approaches to treatmentand management often differ out of necessity.Many of the agents typically used for more persistentcases of psoriasis cannot be used in the samecapacity with pediatric patients, if at all. However,it is important to be vigorous, even aggressive,because psoriasis can potentially be more physicallyand psychologically distressing for youngerpatients. Ahead, I will review data on the prevalenceof pediatric psoriasis and discuss severaltreatment strategies.
Prevalence of Pediatric Psoriasis
Clinicians must be attentive for the diagnosis ofpsoriasis in children. It is believed that between 10percent and one third of patients with psoriasisdevelop the disease during childhood. The occurrenceof two incidence peaks has been suggestedwith one peak in adolescence and the other inadulthood. A recent study from the Mayo Clinicfound the annual incidence of pediatric psoriasis tobe 40.8 per 100,000 compared to 120 per 100,000 inthe adult population.1 Several studies have revealedthat one third of patients develop symptoms of psoriasisduring childhood but are not diagnosed untiladulthood. The Mayo Clinic study does not supporta dual peak in age of onset, but rather a steadyincrease with age overall until the seventh decade,with a more rapid increase until age 35. In children,specifically, there appears to be a more rapidincrease until age seven, thereafter the rate ofdevelopment of psoriasis levels off. Interestingly,there has been a two-fold increase in psoriasis incidencein children from 1974-1999, similar to theincrease seen in the adult population. In addition,incidence is equal between boys and girls.
Chronic plaque psoriasis is the most commonform of psoriasis among children, accounting for 74percent of cases. Guttate psoriasis is also somewhatcommon (14 percent) in children, while pustularand erythrodermic psoriasis are less common.2Importantly, juvenile psoriasis has been associatedwith an increased rate of stress, strep infections, hyperlipedemia, depression, obesity, hypertension,diabetes, arthritis, and Crohn's disease.3 These factorsmay also play a role in increasing incidence ofpsoriasis.
Diagnosis and Treatment
Early diagnosis and appropriate management of psoriasisin childhood, while a challenge, can helplessen psychosocial issues. Management involveseducation of the child and her/his parents concerningthe chronic nature of the disease. Treatment iseven more challenging than in adults because thereare no FDA-approved systemic treatments for pediatricpatients, and, additionally, compliance potentiallyis a more significant issue. Treatment optionsin children often require special care in order not toendanger the development or the future health ofthe child.4
Topical therapies. Topical corticosteroids can beused to treat pediatric psoriasis, but they may havean increased likelihood of more frequent andsevere adverse events in children. Class 1, 2, or 3steroids should be used with extreme caution.These agents should not be used for longer thantwo weeks and should not be used on the face orintertriginous areas. It is also important to keep inmind there is higher percutaneous absorption inchildren, therefore, to avoid HPA suppression inpatients with less than 10 percent BSA, 30g/weekwould be an appropriate dosage for topical corticosteroids.
Topical calcineuron inhibitors have been used onthe face and intertriginous areas with good and saferesults.4 Topical Vitamin D analogues, such as calcipotriene(Taclonex, Leo Pharma) and calcitriol(Vectical, Galderma), provide reliable efficacy andsafety, especially when used in combination.However, their effectiveness may be limited topatients with less than 20 percent BSA.
Light therapy. Another option worth consideringis Narrowband UVB (NB-UVB), which can be aneffective modality in children with moderate tosevere psoriasis. PASI 90 has been achieved withNB-UVB in 60 percent of patients.8 PUVA can beused if NB-UVB fails, however its use should belimited to no more than one or two courses, as it iswell-documented that over 150 treatments increasesthe risk of squamous cell carcinoma five- to sixfold.
Systemic agents. There are no FDA-approved systemictreatments for children and adolescents withmoderate to severe psoriasis; therefore systemicdrugs should be used sparingly. Acetretin may beused in refractory cases, as an adjunct to phototherapyor in pustular or exfoliative erythrodermic psoriasis.For rapid control of exfoliative erythroderma,cyclosporine 3-5mg/kg can be helpful as well.Cyclosporine can also be effective in treating plaquepsoriasis. In addition, Methotrexate has been shownto be efficacious at 0.2-0.4mg/kg once per week,and can be used for many months.9
Biologics. Although etanercept (Enbrel, Amgen)and adalimumab (Humira, Abbott) are FDAapprovedfor Juvenile Rheumatoid Arthritis (JRA) inindividuals as young as age four, biologics are onlyapproved in the US for psoriasis in patients over theage of 18.
Studies have been limited due to the concernover the possible increased likelihood of malignancyin children, despite the lack of evidence showing aclear causal relationship.5 However, biologics can besafe and effective, provided that physicians are cautious and attentive to family history and risk-benefitprofile ratios for each patient.6 One study evaluatedthe effects of etanercept 0.8mg/kg (maximum 50mg)in patients between the ages of four and 17. Patientsreceived etanercept or placebo once weekly for 12weeks, followed by an open label extension for 24weeks.7 At 12 weeks, 57 percent of those receivingetanercept achieved PASI 75, compared to 11 percentof those in the placebo group. At 36 weeks, 68percent of etanercept-treated patients achieved PASI75. Safety data were encouraging.7 Serious adverseevents were comparable between drug and placebo,with no reported cases of death, cancer, severeopportunistic infections, or demylentating diseasereported. Infections in the etanercept group includepilonidal cyst, acute viral syndrome, blood culturepositive bacteremia, and increase in upper respiratoryinfections and nasopharyngitis.
In June of 2008, an FDA advisory committeevoted to recommend the approval of etanercept forthe treatment of pediatric psoriasis. However,Amgen opted to drop its bid for approval when theFDA asked for additional tests. Subsequently, ablack box was implemented on TNF-inhibitors inchildren based on possible increase risk of lymphomaand leukemia. Etanercept should thereforenot be used for children with a family history oflymphoma or leukemia, nor should it be prescribedfor patients with Chrons disease, unless there areno other viable options. However, with proper monitoring,it can be effective in children as young asthree years old.6
The lack of approved medications for the treatmentof pediatric psoriasis has unfortunately resulted inloosely defined guidelines and less aggressiveapproaches to treatment. However, despite havingfewer choices, physicians should understand thatkids with psoriasis want and deserve to be treatedwith the finest care. Despite the physical pains psoriasiscan cause, children with psoriasis (as well astheir parents) can be equally affected by the emotionalburden of the disease.4 Teasing at school andpotentially greater fears of the unknown can exacerbatethe emotional impact of psoriasis in children.Therefore it is important to be aggressive when navigatingthe therapeutic options but cautious withselection and administration.
Pediatric patients will likely require more time todiscuss risk benefit ratios and prognosis, both toallow the patient and parent/s to feel comfortableand, for the physician, to allow for thorough considerationand review of patient history and the risksassociated with each option.
Beyond therapeutic selection, it is essential thatphysicians become parents' allies by bringing thechild onto the treatment team. As has been reportedin the treatment of acne patients, successful treatmentoften benefits from the patient-physician relationshipwhereby the two determine the optimaltreatment plan in which compliance factors—whichare more difficult to execute with children—areconsidered.7
Although it can be a challenge to maintain thebalance between caution and aggressiveness, thetreatment of this unique and difficult-to-treat conditionis particularly rewarding when you achievesuccess and can bring relief to children with pediatricpsoriasis.
Dr. Bagel is on the speaker's bureau for Abbott Labs, Amgen,Centocor, Galderma, and Leo Pharma.
A lack of approved medications for the treatmentof pediatric psoriasis has unfortunately resulted in loosely definedguidelines and less aggressive approaches to treatment. For patientswith less than 10 percent BSA, topical vitamin D analogue ointmentsrepresent a good starting point for therapy. However, for patientswith greater than 10 percent BSA, topical steroids may be necessary,especially when combined with topical vitamin D therapy. The nextstep would be to administer Narrowband UVB light therapy (ifpossible), and then consider retinoids and systemic agents, such asmethotrexate or etanercept. Finally, it is essential that physiciansbecome patients' allies by bringing children and parents onto thetreatment team.
While some young children have the ability to understand theirdisease and how treatment can benefit them, all pediatricpatients with psoriasis can benefit from talking about their conditionwith people who will understand their burdens and canhelp them better understand it. In addition, partnering with parentsand encouraging them to join the National PsoriasisFoundation (www.psoriasis.org; 800-723-9166) can help.Participating in NPF-sponsored walks creates opportunities forchildren with psoriasis to get to know other people with psoriasisand helps greatly in allowing them to cope with their condition.In addition, it enables moms and dads to interact with other parentsof other families that are affected by the disease. For moreinformation, patients can call 877-825-WALK (9255).