Chronic cutaneous lupus erythematosus presenting as atypical acneiform and comedonal plaque: case report and literature review.

Introduction Chronic cutaneous lupus erythematosus (CCLE) usually presents as characteristic erythematous patches and infiltrated coin-shaped plaques. However, there are some atypical clinical variants that may mimic other dermatological conditions. Haroon et al. reported in 1972 an unusual presentation of CCLE with hypertrophic follicular scars seen in acne vulgaris. Acneiform presentation is one of the most rarely reported and one of the most confusing, as it resembles a very common inflammatory skin disease. A brief review of the literature using PubMed found only nine other reports. Case report A 32-year-old woman presented with two-year pruritic infiltrated acneiform and comedonal eruption on the right chin treated as acne with isotretinoin without improvement. On examination the patient presented with erythematous-infiltrated plaque, papules, open comedones, pitting scars and hypopigmented atrophic scars on the right chin area and scalp hair loss. An incisional skin biopsy on the chin and scalp lesions was performed and the anatomopathological and immunofluorescence exam showed findings that are consistent with CCLE. Additional tests ruled out systemic involvement. The patient was treated with prednisone and chloroquine diphosphate with great improvement. After four years the lesion is stable, with some scarring. Discussion In a literature review we found nine other cases of acneiform presentation of lupus erythematosus: Three cases were systemic lupus erythematosus (SLE) and seven others were diagnosed as CCLE (including our patient). All three patients who had SLE tested positive for antinuclear antibodies (ANA), and only one patient with CCLE, had a low titer of positive ANA (1:80). Ages varied from 24 to 60 years old, with a median of 32 years old, the same as our patient's age and consistent with the literature. Seven were females and three were males, with a ratio of 2.3:1. Most cases, such as our patient, showed acneiform lesions mainly on the face, a common site of typical CCLE. The present case and literature review illustrates the need to expand the differential diagnosis of atypical acneiform and comedonal lesions. CCLE should be considered especially in a localized lesion, which can be itchy and does not improve with conventional treatment for acne vulgaris.