Trichorrhexis Nodosa: A Distinctive Presentation After Tumor Necrosis Factor-Alpha Inhibitor Therapy

A 61-year-old woman developed trichorrhexis nodosa (TN), a hair shaft disorder, after starting etanercept therapy for chronic plaque psoriasis. Despite no changes in hair care practices, she experienced hair breakage localized to the crown. TN is typically caused by trauma, but in this case, the timing of etanercept initiation and hair breakage suggested a potential link. Etanercept, a TNF-α inhibitor, might disrupt hair fibre development, impairing cuticle formation and increasing hair fragility. The patient's psoriasis improved with etanercept, but her hair issues persisted even after switching to adalimumab. This case was the first to suggest an association between etanercept and TN.