Diagnóstico diferencial de las lesiones cutáneas en el lupus eritematoso

Patients with lupus erythematosus (LE) frequently develop manifestations in skin and/or mucosa, some are diagnostic criteria of systemic LE. These skin or mucosa LE lesions can be classified as specific (if they have the LE characteristic histological changes) or as non-specific. The first are divided in acute, subacute or chronic cutaneous LE. Non-specific group is constituted by several manifestations classified as secondary or non-secondary to vascular damage. Since in some cases these lesions can indicate systemic activity, their correct identification is important for the diagnosis and management of LE patients, This implies ruling out several entities included in the wide differential diagnosis of LE skin or mucosa lesions, as scaling and erythematous dermatitis, photodermatitis, reactive inflammatory dermatitis, annular erythemas, autoimmune processes and skin infections, taking account of the clinical features, distribution and evolution of the lesions. In some instances, a skin biopsy is needed to establish a final diagnosis by a conventional histopathology and the demonstration by immunofluorescence techniques of specific deposits in LE lesions.