Diagnosis
Discoid lupus erythematosus
Diagnosis of DLE involves a thorough examination of the distribution and clinical appearance of plaques, often confirmed via skin biopsy. Features observed in biopsy specimens can vary depending on the stage of DLE but typically include interface dermatitis involving hair follicles, along with a perivascular and peri-appendageal lymphocytic infiltrate in the upper and lower dermis.
Other features may include epidermal vacuolation, apoptotic basal cells, hyperkeratosis, thickening of the basement membrane, and dermal fibrosis. Blood tests such as a full blood count, renal function tests, and antinuclear antibody (ANA) tests may also be conducted, although ANA is frequently not detected in DLE cases. Urine analysis may also be performed as part of the diagnostic process.