Supplementary Material for: Keratoderma-like T Cell Dyscrasia: A Case Report

Introduction: Cutaneous T-cell dyscrasia (CTCD) encompasses a heterogeneous group of T-cell infiltrates, often clonal and epitheliotropic. While the etiology remains unclear, certain medications, including statins, have been linked to CTCL development. Case Description: A patient presented with a pruritic, scaly eruption on her palms and soles unresponsive to topical steroids for one month. Histopathological examination revealed compact orthokeratosis, mild lymphocytic infiltrate with focal exocytosis, and atypical lymphocytes. Immunophenotyping demonstrated a predominance of CD3+ T-cells with a 1:1 CD4/CD8 ratio and reduced CD7 expression. The clinical presentation, histopathology, and immunophenotype supported a diagnosis of statin-induced CTCD. Conclusion: Statin discontinuation led to complete symptom resolution, emphasizing the reversibility of drug-induced T-cell dyscrasia. This case highlights the importance of a detailed medication history, as drug-induced T-cell dyscrasia, unlike classic CTCD with its characteristic lymphoid atypia, phenotypic abnormalities, and clonality leading to a refractory course, can be reversed by drug withdrawal.