Pediatric nail psoriasis is a condition that has not been extensively studied. The prevalence of nail alterations in pediatric patients with psoriasis varies among different studies, ranging from 17% to 39.2%.1 Nail pitting, onycholysis associated with subungual hyperkeratosis, paronychia, and pachyonychia are the most frequent features of psoriatic nail involvement in children.2,3 The management of nail psoriasis in children and adolescents is critical due to the quality-of-life impact, from potential functional impairment issues to the obvious cosmetic problems, which can aggravate the psychologic distress and social embarrassment of patients with psoriasis. Despite the emergence of modern potent systemic agents to treat chronic plaque psoriasis, nail psoriasis often is refractory to treatment.4 Coupled with the limited on-label options for psoriasis treatment in children, the management of nail psoriasis in this special patient group constitutes an even greater therapeutic challenge. This report aims to summarize the limited existing data on the successful management of nail psoriasis in the pediatric population.
Reviewing the Literature on Nail Psoriasis
We conducted a search of PubMed articles indexed for MEDLINE, Embase, and Scopus using the following Medical Subject Headings key terms: nail psoriasis and children, juvenile, pediatric. Additional articles were identified from the reference lists of the retrieved articles and citations. Our search included reports in the English language published from 2000 to 2019. The selection process included the following 2 steps: screening of the titles and abstracts, followed by evaluation of the selected full-text articles.
Topical Treatments for Nail Psoriasis
Because most systemic antipsoriatic treatments that can be administered in adult patients have not yet been granted an official license for administration in children, topical treatments are considered by many physicians as the preferred first-line therapy for psoriatic nail involvement in pediatric patients.5,6 However, only scarce data are available in the literature concerning the successful use of local agents in pediatric patients with psoriasis.
The main limitation of local treatments relates mostly to their impaired penetration into the affected area (nails). To optimize drug penetration, some authors suggest the use of potent keratolytic topical preparations to reduce the nail volume and facilitate drug absorption.7 A popular suggestion is trimming the onycholytic nail plate followed by 40% urea avulsion to treat subungual hyperkeratosis8 or simply the use of occlusive 40% urea in petroleum jelly.9 Other approaches include clipping the onycholytic nail over the diseased nail bed or processing the nail plate through grinding or even drilling holes with the use of mechanical burrs or ablative lasers to enhance the penetration of the topical agent.7
A frequent approach in pediatric patients is clipping the detached nails combined with daily application of calcipotriene (calcipotriol) and steroids, such as betamethasone dipropionate.5,8 Reports on the use of regimens with clobetasol propionate ointment 0.05% under occlusion, with or without the concomitant use of calcipotriol solution 0.005%, also are present in the literature but not always with satisfactory results.10,11 Another successfully administered topical steroid is mometasone furoate cream 0.1%.12 Although the use of intralesional triamcinolone acetonide also has demonstrated encouraging outcomes in isolated reports,13 associated adverse events, such as pain and hematomas, can result in tolerability issues for pediatric patients.7
Piraccini et al14 described the case of an 8-year-old patient with pustular nail psoriasis who showed improvement within 3 to 6 months of treatment with topical calcipotriol 5 μg/g as monotherapy applied to the nail and periungual tissues twice daily. Another approach, described by Diluvio et al,15 is the use of tazarotene gel 0.05% applied once daily to the affected nail plates, nail folds, and periungual skin without occlusion. In a 6-year-old patient with isolated nail psoriasis, this treatment regimen demonstrated notable improvement within 8 weeks.15
Systemic Treatments for Nail Psoriasis
Data on the successful administration of systemic agents in pediatric patients also are extremely scarce. Due to the lack of clinical trials, everyday practice is mostly based on isolated case series and case reports.