Clinical and histopathologic features and immunologic variables in patients with severe chilblains. A study of the relationship to lupus erythematosus.

We investigated 33 patients affected with chilblain lesions following a persisting course of more than 1 month. We focused on the incidence of an underlying connective tissue disease, mostly lupus erythematosus (LE), and we analyzed features of idiopathic chilblains compared with those of chilblain lesions associated with connective tissue disease. We also carried out a prospective follow-up of patients. Eleven patients included in the study were free of any clinical and/or laboratory abnormality suggestive of connective tissue disease, while 22 of 33 patients showed 1 or several abnormalities raising suspicion for connective tissue disease, and among them 8 had a diagnosis of systemic lupus erythematosus (SLE) established at initial evaluation based on the American College of Rheumatology revised criteria. The comparative analysis of patients with idiopathic chilblains and patients with chilblains associated with LE showed that female sex and persistence of lesions beyond cold seasons were significantly associated with chilblain LE. Histopathologic studies of chilblain lesions did not reveal features typical of LE in any case, but revealed a higher incidence of a deep perisudoral infiltrate in idiopathic chilblains. In patients showing signs of connective tissue disease, positive cutaneous immunofluorescence was correlated with the presence of circulating antinuclear antibodies. Two patients had an ascertained diagnosis of SLE with severe manifestations during prospective follow-up, requiring treatment with oral steroids in both cases. Chilblains following a chronic course may reveal connective tissue disease, and patients affected with chilblains associated with autoimmune abnormalities may develop severe SLE. Accordingly, long-term follow-up of these patients is warranted.