Classification of lupus erythematosus based upon cutaneous manifestations. Dermatological, systemic and laboratory findings in 191 patients.

BACKGROUND: Lupus erythematosus (LE) is a multi-organ-system disease, the characteristics of which are reflected in the 1982 American Rheumatism Association (ARA) criteria for systemic lupus erythematosus (SLE). From a dermatological point of view, only the presence of LE-specific histopathology is necessary and sufficient for the diagnosis of LE. The association between the type of LE-specific skin lesion and the severity of extracutaneous manifestations of LE has not yet been investigated systematically.

OBJECTIVE: The aim of this study was to evaluate, according to the type of LE skin lesions, the prevalence of the 1982 criteria for SLE.

METHODS: We selected 191 patients whose skin lesions were histologically diagnosed as LE specific. Patients were classified on the basis of skin disease, and their clinical and laboratory data were analyzed.

RESULTS: Of 191 patients, 130 (68%) exhibited only one type of LE-specific skin lesion (monomorphic), 55 (29%) had two types (bimorphic) and the remaining 6 (3%) displayed three types (trimorphic). Nineteen of 22 (86%) patients who presented discoid lupus skin lesions above the neck without other eruptions were classified in the cutaneous-limited LE spectrum. Of 116 patients with acute lupus skin lesions (malar rash), 83 (72%) clearly fulfilled the 1982 ARA criteria for SLE. In skin lesions of LE profundus, chilblain lupus, subacute lupus (annular-polycyclic erythema and the papulosquamous variant), there were no significant correlations between the type of eruption and the severity of extracutaneous manifestations.

CONCLUSION: Patients with acute lupus skin lesions could usually be classified as suffering from SLE, whereas monomorphic patients with localized discoid lesions rarely exhibited extracutaneous manifestations. This tendency was less distinct in bimorphic patients. Almost all patients with subacute skin lesions were bimorphic or trimorphic, which might be due to genetic or racial differences between Japanese and other populations.