By Gary M. White, MD
Psoriasis most commonly has its onset in adulthood, but occasionally it may affect children.
The typical red, scaly papules and plaques are seen.
For mild disease, all the usual topical treatments for an adult apply here. For more advanced disease requiring systemic therapy, nbUVB is a good choice. The child must be confident enough to go into the light box. A parent may accompany the child, being totally covered so he/she does not receive the UV during treatment.
Taclonex (betamethasone/calcipotriene) topical suspension is FDA approved for scalp psoriasis in children aged 12-17 daily for up to 8 weeks.
In children with psoriasis, methotrexate 0.2-0.7 mg/kg/week has been recommended. An initial test dose of 1.25 mg to 5 mg, followed in 1 week by laboratory monitoring is recommended. Conservative dose escalations of 1.25-5 mg/week are advised until therapeutic effect is obtained, followed by a slow taper to a beneficial maintenance dose. The 2.5 mg scored tablet can be split or crushed and given with non-milk food.
Etanercept has been studied in children with psoriasis and is now FDA-approved for pediatric patients aged 4–17 years with chronic moderate-to-severe plaque psoriasis. Etanercept is also-FDA approved for children down to 2 years of age with polyarticular juvenile idiopathic arthritis. The risk of cancer, e.g. lymphoma is a concern, but the vast majority of children that developed cancer (half lymphoma) on TNF agents were on treatment for diseases other than psoriasis and were also on other immunosuppressive agents as well. A 5-year, open-label study of 182 children with psoriasis aged 4-17 years found etanercept to be generally well-tolerated and efficacy was maintained [JAAD 2016;74;280]. Etanercept has been combined with methotrexate for the treatment of childhood psoriasis [PD 2016;33;142].
Ustekinumab is FDA approved for adolescents age 12-17 with moderate to severe psoriasis. It is usually used alone, but has been combined with methotrexate [PD 2016;33;142].
Adalimumab is currently FDA approved for juvenile idiopathic arthritis. It has been used with success in children both alone and in combination with methotrexate [PD 2016;33;142].
Retinoids, like acitretin, can be used in children starting at six months of age. Acitretin was found to be modestly effective in 18 patients with a median age of 9.5 years at the start of therapy [PD 2016;33;530]. 44% of patients achieved good results.
Cyclosporine dosing for children is between 1.5-5 mg/kg/day.
Short-contact dithranol therapy can be used effectively for children with psoriasis [British J Dermatology Feb 2014]. One experts protocol as performed at a day care center (page 107) is summarized here; "Dithranol cream (0.01 - 4%) is diffusely applied on the trunk, arms and legs. The concentration is gradually increased after nine consecutive days of treatment, according to the tolerance and therapeutic response of the patient. Within these nine days, the dithranol cream is applied for 15 minutes at day 1 - 3, for 30 minutes at day 4 - 6, and for 45 minutes at day 7 - 9. It is washed off by shower and, afterwards, an emollient is applied on the treated skin."