Recalcitrant trametinib‐induced paronychia treated successfully with topical timolol in a pediatric patient

Abstract

Paronychia has been described as a side effect in patients undergoing treatment with MEK (mitogen activated protein kinase enzyme) inhibitors. It is usually a recurrent condition that can have a significant impact in the quality of life. Topical beta blocker treatment has been described as an effective therapy in antineoplastic-induced pyogenic granulomas and in antineoplastic-induced paronychia. We describe the first case treated with topical timolol for a trametinib-induced paronychia in a pediatric patient that allowed to continue the third line antineoplastic therapy for his glioma.

Dermatologic toxicities of targeted antineoplastic agents and immune checkpoint inhibitor therapy in pediatric patients: A systematic review

“…Martínez‐de‐Espronceda et al 40 . successfully treated a patient's trametinib‐induced paronychia with topical timolol gel twice daily.…”

“…Four phase I/II clinical trials, [31][32][33][34] five retrospective reviews, 20,21,[35][36][37] and six case reports [38][39][40][41][42][43] described cAEs associated with trametinib or selumetinib. The cAEs reported in all four clinical trials [31][32][33][34] were mucositis (5.3%-50%), dry skin (2.6%-68%), and acneiform rash (7.9%-62%).…”

“…38,39,42,43 Successful treatment regimens were low-dose isotretinoin and systemic antibiotics, including doxycycline, minocycline, and fluconazole. Martínez-de-Espronceda et al 40 successfully treated a patient's trametinib-induced paronychia with topical timolol gel twice daily. In other studies, paronychia also responded variably to dose reductions, dilute bleach soaks, topical steroids, topical antibiotics, and chemical cautery with silver nitrate.…”

MEK inhibitor‐induced paronychia in a paediatric population: A tertiary centre experience

“…In grade 2 paronychia, topical treatments are the first line. Application in occlusion during the night and treatment combination may increase efficacy 13–15 . Options include topical corticosteroids (e.g.…”

“…timolol 0.5%-1% gel or cream twice daily) and brimonidine 0.2% gel, a selective alpha-2 adrenergic receptor agonist. 13,16 Treatment is usually required for long periods (e.g. over a month).…”