Cutaneous lupus mucinosis: a review of our cases and the possible pathogenesis.

Cutaneous lupus mucinosis (CLM) is a rare variant of lupus erythematosus eruptions. Our 5 cases with CLM were reviewed. All were men with systemic lupus erythematosus (SLE). CLM occurred as asymptomatic cutaneous papules, nodules, or plaques on the trunk, upper and lower extremities, and face. Histopathology of CLM mainly revealed abundant mucin deposits among splayed collagen bundles throughout the dermis. However, some CLM lesions showed discoid lupus erythematosus-like epidermal and dermal changes and/or lupus profundus. Vasculitis was also revealed in the CLM lesions of 2 cases. The pathogenesis of CLM may be closely related to its two important features, the male preponderance and the association with SLE. Vasculopathy may also be involved in the development of CLM.