A case of discoid lupus erythematosus presenting as a hypopigmented patch: A diagnostic challenge

Discoid lupus erythematosus (DLE), a chronic cutaneous form of lupus erythematosus, classically presents with erythematous, scaly plaques in sun-exposed areas. However, its atypical manifestations can pose significant diagnostic challenges. We report a rare presentation of DLE in a 45-year-old woman who developed an ill-defined, asymptomatic hypopigmented patch over the upper lip. Initial differential diagnoses included Hansen’s disease, vitiligo, and pityriasis versicolor. Wood’s lamp examination and KOH mount were noncontributory. Histopathology from a skin biopsy revealed features characteristic of DLE, including follicular plugging, basal cell degeneration, pigment incontinence, and dermal lymphocytic infiltrates. A positive ANA test supported the autoimmune etiology. The lesion was resolved with topical corticosteroids. This case underscores the importance of considering DLE in the differential diagnosis of hypopigmented lesions, especially in sun-exposed areas, and highlights the diagnostic value of histopathology. Recognizing such atypical presentations is vital to avoid misdiagnosis and ensure timely management.