Tumor Necrosis Factor Inhibitor-Induced Psoriasis in a Pediatric Crohn's Disease Patient Successfully Treated with Ustekinumab.

BACKGROUND: Tumor necrosis factor (TNF) inhibitors are widely used in pediatric patients with inflammatory bowel disease, as well as psoriasis. However, there is growing evidence that these medications can also paradoxically induce a psoriasiform skin reaction in a subset of patients. GOALS: We seek to share our experience in treating severe TNF inhibitor-induced psoriasis in a pediatric patient with Crohn’s disease. STUDY: We report a case of a 10-year-old female with Crohn’s disease, who developed psoriasis after twelve months of infliximab therapy. Her skin disease was recalcitrant to topical therapies, methotrexate, and phototherapy. RESULTS: The patient was transitioned to ustekinumab with significant improvement in her symptoms and maintenance of remission of her bowel disease. CONCLUSION: This is the first reported case of a school-age pediatric patient with TNF inhibitor-induced psoriasis treated with ustekinumab. Controlled trials are warranted to fully assess the safety and efficacy of ustekinumab for treating TNF inhibitor-induced psoriasis in the pediatric population.J Drugs Dermatol. 2020;19(3): doi:10.36849/JDD.2020.2106.

Pityriasis Lichenoides in Childhood: Review of Clinical Presentation and Treatment Options.

Pityriasis lichenoides (PL) is a skin condition of unclear etiology that occurs not uncommonly in childhood. It is often classified into the acute form, pityriasis lichenoides et varioliformis acuta (PLEVA), and the chronic form, pityriasis lichenoides chronica (PLC). We performed a comprehensive review of the English-language literature using the PubMed database of all cases of childhood PL reported from 1962 to 2014 and summarized the epidemiology, clinical features, treatment options, and prognosis of this condition in children. The proposed etiologies are discussed, including its association with infectious agents, medications, and immunizations and evidence for PL as a lymphoproliferative disorder. We found an average age of PL onset of 6.5 years, with a slight (61%) male predominance. We also found that PLEVA and PLC tend to occur with equal frequency and that, in many cases, there is clinical and histopathologic overlap between the two phenotypes. When systemic therapy is indicated, we propose that oral erythromycin and narrowband ultraviolet B phototherapy should be first-line treatment options for children with PL since they have been shown to be effective and well tolerated. In most cases, PL follows a benign course with no greater risk of cutaneous T-cell lymphoma, although given the rare case reports of transformation, long-term follow-up of these patients is recommended.