GENITAL discoid lupus may mimic common inflammatory dermatoses, making biopsy critical in chronic genital rashes.
Genital Discoid Lupus Remains Rare
Genital discoid lupus erythematosus is an uncommon presentation of chronic cutaneous lupus erythematosus and may be overlooked because of its overlap with more familiar inflammatory and infectious genital dermatoses. Discoid lupus erythematosus most often presents as erythematous, scaly plaques with hyperpigmentation, typically affecting sun exposed sites such as the scalp and cheeks.
Involvement of genital skin is rare. The literature review identified only 14 previously documented cases, with most reported in female patients and with a particular tendency toward vulvar involvement. This rarity creates a diagnostic challenge for clinicians evaluating long standing genital rashes, especially when symptoms and morphology resemble lichen sclerosus, lichen simplex chronicus, psoriasis, or infectious dermatoses.
Chronic Genital Dermatoses May Need Biopsy
The reported case involved a 60-year-old female with systemic sclerosis and Raynaud’s syndrome who presented with well demarcated, erythematous, keratotic plaques with atrophy affecting the inguinal creases and medial buttocks. The eruption had persisted for years and was associated with pruritus, as well as recent pain when sitting.
Initial clinical differential diagnoses included lichen sclerosus, lichen simplex chronicus, and psoriasis. Histopathologic assessment was decisive, showing orthokeratosis and parakeratosis, epidermal hyperplasia, thickened basement membrane, dilated blood vessels, and perivascular inflammation. Plasmacytoid dendritic cells were identified in the dermis and highlighted by CD123 immunohistochemical staining, supporting a diagnosis of discoid lupus erythematosus.
Systemic evaluation did not show systemic lupus erythematosus. The patient was started on topical corticosteroids.
Histopathology Supports Earlier Recognition
This case reinforces the need to include discoid lupus erythematosus in the differential diagnosis of chronic genital dermatoses, particularly when lesions are persistent, keratotic, atrophic, or refractory to empiric management. Although genital discoid lupus is rare, delayed recognition may occur when clinicians anchor on more common genital inflammatory diseases.
For healthcare professionals, the key clinical message is clear: chronic genital plaques with atypical or persistent features warrant histopathologic evaluation. Biopsy can distinguish discoid lupus erythematosus from clinically similar dermatoses and help guide appropriate treatment while prompting evaluation for systemic lupus erythematosus when indicated.
Reference
Abu-Dayeh A et al. Discoid Lupus Erythematous in Genital Skin: A Case Report and Review of the Literature. J Cutan Pathol. 2026;DOI:10.1111/cup.70145.
Featured Image: Daniel Ernst on Adobe Stock.
