Supplementary Material for: Possible Treatment of Topical Steroid Withdrawal with methylene blue case report: implications for mitochondrial pathology

We present a case report of an 8-year-old girl with atopic dermatitis (AD) who was treated with topical corticosteroids (TCS) that included high potency agents. Her initial symptoms were limited to the chest and back. After approximately 3 months of treatment with escalating potency, the perceived lack of TCS efficacy prompted her parents to discontinue TCS while maintaining emollients. Four weeks later, the patient developed new symptoms consistent with topical steroid withdrawal (TSW) involving the face, neck, and legs. The family attempted alternative-medical treatments including turmeric, vitamin D3, and more without clinical response, before observing symptomatic relief with a self-initiated, low dose of methylene blue (MB). Although the merits of the case are anecdotal, existing literature suggests that TSW is associated with mitochondrial complex I dysfunction, which could explain the observed clinical benefit. Given that both TSW and AD have natural temporal variations, we cannot extrapolate conclusively based on a single report. However, our observations are consistent with the hypothesis that TSW is an induced, but targetable, defect in mitochondrial complex I function that warrants further investigation. At minimum, providers should be aware of the TSW patient community’s consideration of MB as an alternative therapy, especially given the lack of data on long-term safety.