Subacute cutaneous lupus erythematosus with a psoriasiform presentation: A diagnostic clinical conundrum.

KEY CLINICAL MESSAGE: For practitioners experiencing worsening psoriasis, subacute cutaneous lupus erythematosus (SCLE) with a psoriasiform presentation should be ruled out. Initial treatment for a presumptive diagnosis of psoriasis using hydroxychloroquine or ultraviolet phototherapy may cause SCLE to worsen.

ABSTRACT: Psoriasiform subacute cutaneous lupus erythematosus is an unusual presentation scarcely reported in literature. We report a case of a 54-year-old man who presented with an itchy, papulosquamous rash of the upper extremities and face for 7 months. The initial physical examination revealed the classical morphology of psoriasis. One and a half years after the diagnosis of clinical worsening, the patient noticed a new papular eruption on the right posterior upper arm. A skin biopsy was performed, confirming a diagnosis of subacute cutaneous lupus erythematosus. This case report highlights the importance of considering rare presentations of cutaneous lupus erythematosus and therapeutic challenges in management.