prurigo nodularis (PN) is a chronic inflammatory skin disease marked by intensely itchy papules. Its development is linked to inflammatory cytokines like interleukin-4 (IL-4), interleukin-13 (IL-13), and interleukin-31 (IL-31), along with the JAK-STAT signaling pathway.^1,2 PN frequently enough occurs alongside Th2-driven inflammatory conditions, notably atopic dermatitis (AD). Constant scratching from long-term AD can cause nodular lesions similar to those in PN. Research on PN in children is scarce, with an estimated prevalence of about 21.6 per 100,000.³

Atopic dermatitis (AD) is widespread, affecting around 20% of children globally.⁴ A recent meta-analysis indicates a two-way connection between thes conditions, showing that individuals with either are more likely to develop the other.⁵

While studies have shown that dupilumab and JAK1 inhibitors are effective in treating refractory PN in adults,^6-8 there are limited treatment options for children with refractory PN. This article details a case where a child with atopic PN was successfully treated with dupilumab.

Case Report: an 11-Year-Old’s success with Dupilumab

“After 4 weeks of treatment, meaningful improvement was observed in her symptoms and lesions.”

An 11-year-old girl presented with itchy erythema, papules, nodules, and excoriations on her trunk and limbs for nine months, along with a two-year history of allergic rhinitis. Her PP-NRS, IGA, and CDLQI scores were 9, 3, and 12, respectively, with elevated total IgE levels. A skin biopsy from her lower leg showed epidermal hyperkeratosis with parakeratosis, acanthosis, and perivascular infiltration of inflammatory cells in the superficial dermis. Based on these findings, she was diagnosed with prurigo nodularis.

She had previously been treated with upadacitinib, abrocitinib, antihistamines, and other medications. Initially, these treatments provided some relief, but the response diminished, and symptoms returned upon dose reduction. Consequently, she received a loading dose of dupilumab at 600 mg (15 mg/kg), followed by subcutaneous injections of 300 mg (7 mg/kg) every three weeks. By the second week, her PP-NRS score decreased from 9 to 7, the IGA score from 3 to 2, and the CDLQI score from 12 to 6, indicating an early positive response. After four weeks, significant improvement was observed in her symptoms and lesions. The PP-NRS, IGA, and CDLQI scores improved by 77.78%, 66.67%, and 83.33%, respectively.

At week 16, due to financial constraints, the injection interval was extended.